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1.
Nature ; 591(7850): 451-457, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33561864

RESUMO

All coronaviruses known to have recently emerged as human pathogens probably originated in bats1. Here we use a single experimental platform based on immunodeficient mice implanted with human lung tissue (hereafter, human lung-only mice (LoM)) to demonstrate the efficient in vivo replication of severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), as well as two endogenous SARS-like bat coronaviruses that show potential for emergence as human pathogens. Virus replication in this model occurs in bona fide human lung tissue and does not require any type of adaptation of the virus or the host. Our results indicate that bats contain endogenous coronaviruses that are capable of direct transmission to humans. Our detailed analysis of in vivo infection with SARS-CoV-2 in human lung tissue from LoM showed a predominant infection of human lung epithelial cells, including type-2 pneumocytes that are present in alveoli and ciliated airway cells. Acute infection with SARS-CoV-2 was highly cytopathic and induced a robust and sustained type-I interferon and inflammatory cytokine and chemokine response. Finally, we evaluated a therapeutic and pre-exposure prophylaxis strategy for SARS-CoV-2 infection. Our results show that therapeutic and prophylactic administration of EIDD-2801-an oral broad-spectrum antiviral agent that is currently in phase II/III clinical trials-markedly inhibited SARS-CoV-2 replication in vivo, and thus has considerable potential for the prevention and treatment of COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19/prevenção & controle , Citidina/análogos & derivados , Hidroxilaminas/administração & dosagem , Hidroxilaminas/uso terapêutico , Administração Oral , Células Epiteliais Alveolares/imunologia , Células Epiteliais Alveolares/patologia , Células Epiteliais Alveolares/virologia , Animais , COVID-19/imunologia , Quimioprevenção , Quirópteros/virologia , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Citidina/administração & dosagem , Citidina/uso terapêutico , Citocinas/imunologia , Células Epiteliais/virologia , Feminino , Xenoenxertos , Humanos , Imunidade Inata , Interferon Tipo I/imunologia , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Transplante de Pulmão , Masculino , Camundongos , Profilaxia Pós-Exposição , Profilaxia Pré-Exposição , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Replicação Viral
2.
Nature ; 568(7751): 244-248, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30836379

RESUMO

A cure for HIV-1 remains unattainable as only one case has been reported, a decade ago1,2. The individual-who is known as the 'Berlin patient'-underwent two allogeneic haematopoietic stem-cell transplantation (HSCT) procedures using a donor with a homozygous mutation in the HIV coreceptor CCR5 (CCR5Δ32/Δ32) to treat his acute myeloid leukaemia. Total body irradiation was given with each HSCT. Notably, it is unclear which treatment or patient parameters contributed to this case of long-term HIV remission. Here we show that HIV-1 remission may be possible with a less aggressive and toxic approach. An adult infected with HIV-1 underwent allogeneic HSCT for Hodgkin's lymphoma using cells from a CCR5Δ32/Δ32 donor. He experienced mild gut graft-versus-host disease. Antiretroviral therapy was interrupted 16 months after transplantation. HIV-1 remission has been maintained over a further 18 months. Plasma HIV-1 RNA has been undetectable at less than one copy per millilitre along with undetectable HIV-1 DNA in peripheral CD4 T lymphocytes. Quantitative viral outgrowth assays from peripheral CD4 T lymphocytes show no reactivatable virus using a total of 24 million resting CD4 T cells. CCR5-tropic, but not CXCR4-tropic, viruses were identified in HIV-1 DNA from CD4 T cells of the patient before the transplant. CD4 T cells isolated from peripheral blood after transplantation did not express CCR5 and were susceptible only to CXCR4-tropic virus ex vivo. HIV-1 Gag-specific CD4 and CD8 T cell responses were lost after transplantation, whereas cytomegalovirus-specific responses were detectable. Similarly, HIV-1-specific antibodies and avidities fell to levels comparable to those in the Berlin patient following transplantation. Although at 18 months after the interruption of treatment it is premature to conclude that this patient has been cured, these data suggest that a single allogeneic HSCT with homozygous CCR5Δ32 donor cells may be sufficient to achieve HIV-1 remission with reduced intensity conditioning and no irradiation, and the findings provide further support for the development of HIV-1 remission strategies based on preventing CCR5 expression.


Assuntos
Infecções por HIV/terapia , Infecções por HIV/virologia , HIV-1 , Transplante de Células-Tronco Hematopoéticas/métodos , Receptores CCR5/química , Receptores CCR5/genética , Linfócitos T CD4-Positivos/imunologia , Citomegalovirus/química , Citomegalovirus/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/complicações , HIV-1/química , HIV-1/imunologia , Doença de Hodgkin/complicações , Doença de Hodgkin/tratamento farmacológico , Humanos , Receptores CCR5/deficiência , Receptores CCR5/metabolismo , Receptores CXCR4/metabolismo , Transplante Homólogo , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia
3.
BMC Plant Biol ; 21(1): 316, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215204

RESUMO

BACKGROUND: Ergot, caused by the fungal pathogen Claviceps purpurea, infects the female flowers of a range of cereal crops, including wheat. To understand the interaction between C. purpurea and hexaploid wheat we undertook an extensive examination of the reprogramming of the wheat transcriptome in response to C. purpurea infection through floral tissues (i.e. the stigma, transmitting and base ovule tissues of the ovary) and over time. RESULTS: C. purpurea hyphae were observed to have grown into and down the stigma at 24 h (H) after inoculation. By 48H hyphae had grown through the transmitting tissue into the base, while by 72H hyphae had surrounded the ovule. By 5 days (D) the ovule had been replaced by fungal tissue. Differential gene expression was first observed at 1H in the stigma tissue. Many of the wheat genes differentially transcribed in response to C. purpurea infection were associated with plant hormones and included the ethylene (ET), auxin, cytokinin, gibberellic acid (GA), salicylic acid and jasmonic acid (JA) biosynthetic and signaling pathways. Hormone-associated genes were first detected in the stigma and base tissues at 24H, but not in the transmitting tissue. Genes associated with GA and JA pathways were seen in the stigma at 24H, while JA and ET-associated genes were identified in the base at 24H. In addition, several defence-related genes were differential expressed in response to C. purpurea infection, including antifungal proteins, endocytosis/exocytosis-related proteins, NBS-LRR class proteins, genes involved in programmed cell death, receptor protein kinases and transcription factors. Of particular interest was the identification of differential expression of wheat genes in the base tissue well before the appearance of fungal hyphae, suggesting that a mobile signal, either pathogen or plant-derived, is delivered to the base prior to colonisation. CONCLUSIONS: Multiple host hormone biosynthesis and signalling pathways were significantly perturbed from an early stage in the wheat - C. purpurea interaction. Differential gene expression at the base of the ovary, ahead of arrival of the pathogen, indicated the potential presence of a long-distance signal modifying host gene expression.


Assuntos
Claviceps/fisiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Transcriptoma/genética , Triticum/genética , Triticum/microbiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Reguladores de Crescimento de Plantas/farmacologia , RNA-Seq , Fatores de Tempo , Triticum/efeitos dos fármacos
4.
Bull Math Biol ; 82(10): 136, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33057872

RESUMO

Reaction-diffusion processes across layered media arise in several scientific domains such as pattern-forming E. coli on agar substrates, epidermal-mesenchymal coupling in development, and symmetry-breaking in cell polarization. We develop a modeling framework for bilayer reaction-diffusion systems and relate it to a range of existing models. We derive conditions for diffusion-driven instability of a spatially homogeneous equilibrium analogous to the classical conditions for a Turing instability in the simplest nontrivial setting where one domain has a standard reaction-diffusion system, and the other permits only diffusion. Due to the transverse coupling between these two regions, standard techniques for computing eigenfunctions of the Laplacian cannot be applied, and so we propose an alternative method to compute the dispersion relation directly. We compare instability conditions with full numerical simulations to demonstrate impacts of the geometry and coupling parameters on patterning, and explore various experimentally relevant asymptotic regimes. In the regime where the first domain is suitably thin, we recover a simple modulation of the standard Turing conditions, and find that often the broad impact of the diffusion-only domain is to reduce the ability of the system to form patterns. We also demonstrate complex impacts of this coupling on pattern formation. For instance, we exhibit non-monotonicity of pattern-forming instabilities with respect to geometric and coupling parameters, and highlight an instability from a nontrivial interaction between kinetics in one domain and diffusion in the other. These results are valuable for informing design choices in applications such as synthetic engineering of Turing patterns, but also for understanding the role of stratified media in modulating pattern-forming processes in developmental biology and beyond.


Assuntos
Modelos Biológicos , Animais , Biologia do Desenvolvimento , Difusão , Escherichia coli , Humanos , Cinética , Conceitos Matemáticos
5.
J Infect Dis ; 218(9): 1485-1489, 2018 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-29873767

RESUMO

Traditional epidemiological investigation of nosocomial transmission of influenza involves the identification of patients who have the same influenza virus type and who have overlapped in time and place. This method may misidentify transmission where it has not occurred or miss transmission when it has. We used influenza virus whole-genome sequencing (WGS) to investigate an outbreak of influenza A virus infection in a hematology/oncology ward and identified 2 separate introductions, one of which resulted in 5 additional infections and 79 bed-days lost. Results from WGS are becoming rapidly available and may supplement traditional infection control procedures in the investigation and management of nosocomial outbreaks.


Assuntos
Infecção Hospitalar/virologia , Vírus da Influenza A/genética , Influenza Humana/virologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Humanos , Controle de Infecções/métodos , Influenza Humana/epidemiologia , Epidemiologia Molecular/métodos , Sequenciamento Completo do Genoma/métodos
6.
Psychol Med ; 48(16): 2776-2785, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29501072

RESUMO

BACKGROUND: Neurocognitive deficits are often seen as core features of schizophrenia, and as primary determinants of poor functioning. Yet, our clinical observations suggest that individuals who score within the impaired range on standardized tests can reliably perform better in complex real-world situations, especially when performance is embedded within a positive socio-affective context. METHODS: We analyzed literature on the influence of non-neurocognitive factors on test performance in order to clarify their contributions. RESULTS: We identified seven non-neurocognitive factors that significantly contribute to neurocognitive test performance: avolition, dysfunctional attitudes, effort, stress, negative emotions, asociality, and disorganized symptoms. We then proposed an alternative model based on dysfunctional (e.g. defeatist) attitudes and their consequences for motivation and sustained task engagement. We demonstrated that these factors account for substantial variance in negative symptoms, neurocognitive test performance, and functional outcomes. We then demonstrated that recovery-oriented cognitive therapy - which is derived from this alternative model and primarily targets dysfunctional beliefs - has been successful in the treatment of low functioning individuals with schizophrenia. CONCLUSION: The contributions of neurocognitive impairments to poor real-world functioning in people with schizophrenia may be overstated in the literature, and may even be limited relative to non-neurocognitive factors. We offer suggestions for further research to more precisely quantify the contributions of attitudinal/motivation v. neurocognitive factors in schizophrenia.


Assuntos
Atitude , Disfunção Cognitiva/fisiopatologia , Emoções/fisiologia , Função Executiva/fisiologia , Motivação/fisiologia , Esquizofrenia/fisiopatologia , Comportamento Social , Estresse Psicológico/fisiopatologia , Disfunção Cognitiva/etiologia , Humanos , Esquizofrenia/complicações
7.
Brain Behav Immun ; 69: 304-311, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29233751

RESUMO

Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcus, or PANDAS, is a syndrome of acute childhood onset of obsessive-compulsive disorder and other neuropsychiatric symptoms in the aftermath of an infection with Group A beta-hemolytic Streptococcus (GABHS). Its pathophysiology remains unclear. PANDAS has been proposed to result from cross-reactivity of antibodies raised against GABHS with brain antigens, but the targets of these antibodies are unclear and may be heterogeneous. We developed an in vivo assay in mice to characterize the cellular targets of antibodies in serum from individuals with PANDAS. We focus on striatal interneurons, which have been implicated in the pathogenesis of tic disorders. Sera from children with well-characterized PANDAS (n = 5) from a previously described clinical trial (NCT01281969), and matched controls, were infused into the striatum of mice; antibody binding to interneurons was characterized using immunofluorescence and confocal microscopy. Antibodies from children with PANDAS bound to ∼80% of cholinergic interneurons, significantly higher than the <50% binding seen with matched healthy controls. There was no elevated binding to two different populations of GABAergic interneurons (PV and nNOS-positive), confirming the specificity of this phenomenon. Elevated binding to cholinergic interneurons resolved in parallel with symptom improvement after treatment with intravenous immunoglobulin. Antibody-mediated dysregulation of striatal cholinergic interneurons may be a locus of pathology in PANDAS. Future clarification of the functional consequences of this specific binding may identify new opportunities for intervention in children with this condition.


Assuntos
Anticorpos/imunologia , Doenças Autoimunes/imunologia , Neurônios Colinérgicos/imunologia , Corpo Estriado/imunologia , Interneurônios/imunologia , Infecções Estreptocócicas/imunologia , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Camundongos , Transtorno Obsessivo-Compulsivo
8.
Eur Child Adolesc Psychiatry ; 27(5): 637-643, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29119300

RESUMO

Little is known about the natural history of children with pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections (PANDAS). This study prospectively followed 33 children with PANDAS for up to 4.8 years (mean 3.3 ± 0.7 years) after enrollment in a 24-week randomized, double-blind, placebo-controlled trial of intravenous immunoglobulin (IVIG) (N = 35). Fourteen of eighteen children randomized to placebo received open label IVIG 6 weeks after the blinded infusion, so follow-up results reported below largely reflect outcomes in a population of children who received at least one dose of IVIG. Telephone interviews with the parents of participants found that at the time of phone follow-up, 29 (88%) were not experiencing clinically significant obsessive-compulsive symptoms. During the interim period (6-57 months after entering the clinical trial), 24 (72%) had experienced at least one exacerbation of PANDAS symptoms, with a median of one exacerbation per child (range 1-12; interquartile range 0-3). A variety of treatment modalities, including antibiotics, IVIG, psychiatric medications, cognitive behavioral therapy, and others, were used to treat these exacerbations, and were often used in combination. The outcomes of this cohort are better than those previously reported for childhood-onset OCD, which may support conceptualization of PANDAS as a subacute illness similar to Sydenham chorea. However, some children developed a chronic course of illness, highlighting the need for research that identifies specific symptoms or biomarkers that can be used to predict the longitudinal course of symptoms in PANDAS.


Assuntos
Doenças Autoimunes , Infecções Estreptocócicas , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Estudos Longitudinais , Masculino , Transtorno Obsessivo-Compulsivo , Estudos Prospectivos
9.
Clin Infect Dis ; 65(7): 1127-1135, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575385

RESUMO

Background: The human immunodeficiency virus (HIV) epidemic in Ukraine has been driven by a rapid rise among people who inject drugs, but recent studies have shown an increase through sexual transmission. Methods: Protease and reverse transcriptase sequences from 876 new HIV diagnoses (April 2013-March 2015) in Kiev were linked to demographic data. We constructed phylogenetic trees for 794 subtype A1 and 64 subtype B sequences and identified factors associated with transmission clustering. Clusters were defined as ≥2 sequences, ≥80% local branch support, and maximum genetic distance of all sequence pairs in the cluster ≤2.5%. Recent infection was determined through the limiting antigen avidity enzyme immunoassay. Sequences were analyzed for transmitted drug resistance mutations. Results: Thirty percent of subtype A1 and 66% of subtype B sequences clustered. Large clusters (maximum 11 sequences) contained mixed risk groups. In univariate analysis, clustering was significantly associated with subtype B compared to A1 (odds ratio [OR], 4.38 [95% confidence interval {CI}, 2.56-7.50]); risk group (OR, 5.65 [95% CI, 3.27-9.75]) for men who have sex with men compared to heterosexual males; recent, compared to long-standing, infection (OR, 2.72 [95% CI, 1.64-4.52]); reported sex work contact (OR, 1.93 [95% CI, 1.07-3.47]); and younger age groups compared with age ≥36 years (OR, 1.83 [95% CI, 1.10-3.05] for age ≤25 years). Females were associated with lower odds of clustering than heterosexual males (OR, 0.49 [95% CI, .31-.77]). In multivariate analysis, risk group, subtype, and age group were independently associated with clustering (P < .001, P = .007, and P = .033, respectively). Eighteen sequences (2.1%) indicated evidence of transmitted drug resistance. Conclusions: Our findings suggest high levels of transmission and bridging between risk groups.


Assuntos
Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/genética , Adulto , Análise por Conglomerados , Farmacorresistência Viral/genética , Feminino , Heterossexualidade/fisiologia , Homossexualidade Masculina/genética , Humanos , Masculino , Filogenia , Análise de Sequência de DNA/métodos , Minorias Sexuais e de Gênero , Ucrânia/epidemiologia
10.
Mol Syst Biol ; 12(1): 849, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26814193

RESUMO

Bidirectional intercellular signaling is an essential feature of multicellular organisms, and the engineering of complex biological systems will require multiple pathways for intercellular signaling with minimal crosstalk. Natural quorum-sensing systems provide components for cell communication, but their use is often constrained by signal crosstalk. We have established new orthogonal systems for cell-cell communication using acyl homoserine lactone signaling systems. Quantitative measurements in contexts of differing receiver protein expression allowed us to separate different types of crosstalk between 3-oxo-C6- and 3-oxo-C12-homoserine lactones, cognate receiver proteins, and DNA promoters. Mutating promoter sequences minimized interactions with heterologous receiver proteins. We used experimental data to parameterize a computational model for signal crosstalk and to estimate the effect of receiver protein levels on signal crosstalk. We used this model to predict optimal expression levels for receiver proteins, to create an effective two-channel cell communication device. Establishment of a novel spatial assay allowed measurement of interactions between geometrically constrained cell populations via these diffusible signals. We built relay devices capable of long-range signal propagation mediated by cycles of signal induction, communication and response by discrete cell populations. This work demonstrates the ability to systematically reduce crosstalk within intercellular signaling systems and to use these systems to engineer complex spatiotemporal patterning in cell populations.


Assuntos
4-Butirolactona/análogos & derivados , Comunicação Celular/genética , Transdução de Sinais/genética , Biologia de Sistemas , 4-Butirolactona/genética , 4-Butirolactona/metabolismo , Homosserina/análogos & derivados , Homosserina/genética , Homosserina/metabolismo , Modelos Genéticos , Regiões Promotoras Genéticas , Percepção de Quorum/genética
11.
J Clin Psychopharmacol ; 37(6): 713-716, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29045303

RESUMO

PURPOSE/BACKGROUND: The goals of this study were to determine whether pediatric serum concentration of riluzole is similar to that observed in adults and to determine whether riluzole serum concentration is associated with adverse effects or efficacy in children and adolescents with treatment-refractory obsessive-compulsive disorder. METHODS/PROCEDURES: Data were drawn from previously published studies: 1 open-label trial and 1 randomized controlled trial with an open-label extension phase. Serum was drawn at 24, 36, and 52 weeks in 37 patients who were taking approximately 100 mg riluzole daily (mean dose at 24 weeks, 99 ± 28 mg). FINDINGS/RESULTS: Across all samples, serum riluzole concentration ranged from 7 to 963 ng/mL. At week 24 (n = 37), the median concentration was 76 ng/mL (interquartile range, 53-172 ng/mL). Within-patient concentration was relatively stable. One subject who had the highest serum concentration levels during the study developed pancreatitis after exiting the study. The patient had recently added fluvoxamine to the riluzole regimen. Controlling for concomitant fluvoxamine (in 6 participants) and time of draw, serum riluzole concentration was not associated with obsessive-compulsive disorder symptom severity, nor was it associated with adverse effect profile. IMPLICATIONS/CONCLUSIONS: The dose of riluzole used in these pediatric subjects seems to have achieved serum concentration levels similar to those observed in adults. However, as previously reported in adults, the serum concentration had no discernable relationship to efficacy or adverse effects.


Assuntos
Antagonistas de Aminoácidos Excitatórios/sangue , Antagonistas de Aminoácidos Excitatórios/farmacologia , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Riluzol/sangue , Riluzol/farmacologia , Adolescente , Criança , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Antagonistas de Aminoácidos Excitatórios/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Transtorno Obsessivo-Compulsivo/fisiopatologia , Projetos Piloto , Ensaios Clínicos Controlados Aleatórios como Assunto , Riluzol/administração & dosagem , Riluzol/efeitos adversos
12.
J Exp Biol ; 220(Pt 23): 4440-4449, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28970347

RESUMO

Katydids produce acoustic signals via stridulation, which they use to attract conspecific females for mating. However, direct estimates of the metabolic costs of calling to date have produced diverse cost estimates and are limited to only a handful of insect species. Therefore, in this study, we investigated the metabolic cost of calling in an unstudied sub-Saharan katydid, Plangia graminea Using wild-caught animals, we measured katydid metabolic rate using standard flow-through respirometry while simultaneously recording the number of calls produced. Overall, the metabolic rate during calling in P. graminea males was 60% higher than the resting metabolic rate (0.443±0.056 versus 0.279±0.028 ml CO2 h-1 g-1), although this was highly variable among individuals. Although individual call costs were relatively inexpensive (ranging from 0.02 to 5.4% increase in metabolic rate per call), the individuals with cheaper calls called more often and for longer than those with expensive calls, resulting in the former group having significantly greater cumulative costs over a standard amount of time (9.5 h). However, the metabolic costs of calling are context dependent because the amount of time spent calling greatly influenced these costs in our trials. A power law function described this relationship between cumulative cost (y) and percentage increase per call (x) (y=130.21x-1.068, R2=0.858). The choice of metric employed for estimating energy costs (i.e. how costs are expressed) also affects the outcome and any interpretation of costs of sexual signalling. For example, the absolute, relative and cumulative metabolic costs of calling yielded strongly divergent estimates, and any fitness implications depend on the organism's energy budget and the potential trade-offs in allocation of resources that are made as a direct consequence of increased calling effort.


Assuntos
Comunicação Animal , Metabolismo Energético , Ortópteros/fisiologia , Comportamento Sexual Animal , Asas de Animais/fisiologia , Animais
13.
J Vasc Interv Radiol ; 28(5): 749-756.e2, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28292637

RESUMO

PURPOSE: To evaluate patterns and predictors of peripherally inserted central catheter (PICC)-related occlusion. MATERIALS AND METHODS: Data from a multihospital study were used to examine factors associated with PICC occlusion. Occlusion was defined if documented in the medical record or when tissue plasminogen activator was administered for occlusion-related concerns. Mixed-effects logistic regression was used to predict occlusion, controlling for patient-, provider-, device-, and hospital-level characteristics. RESULTS: A total of 14,278 PICCs placed in 13,408 patients were included. Of these, occlusion developed in 1,716 PICCs (12%) in 1,684 patients. The most common indications for PICC insertion were intravenous antibiotic therapy (32.7%), difficult intravenous access (21.5%), and central access (13.7%). PICCs placed in the right arm had decreased odds of occlusion compared with those in the left arm (odds ratio [OR] = 0.82; 95% confidence interval [CI] = 0.72-0.94). Verification of catheter tip position following insertion was associated with reduction in occlusion (OR = 0.75; 95% CI = 0.61-0.92). Although normal saline solution or heparin flushes did not reduce occlusion, PICCs flushed with normal saline solution and "locked" with heparin were less likely to become occluded (OR = 0.54; 95% CI = 0.33-0.88). Compared with single-lumen devices, double- and triple-lumen PICCs were associated with greater incidences of occlusion (double, OR = 3.07; 95% CI = 2.56-3.67; triple, OR = 3.72; 95% CI = 2.92-4.74). Catheter tip malposition was also associated with occlusion (OR = 1.46; 95% CI = 1.14-1.87). CONCLUSIONS: Several patient, provider, and device characteristics appear associated with PICC occlusion. Interventions targeting these factors may prove valuable in reducing this complication.


Assuntos
Cateterismo Venoso Central/efeitos adversos , Cateterismo Periférico/efeitos adversos , Oclusão de Enxerto Vascular/etiologia , Idoso , Biomarcadores/sangue , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
14.
J Clin Gastroenterol ; 51(3): 268-277, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27380461

RESUMO

BACKGROUND: Advancing fibrosis is regarded as the most important factor when stratifying patients with chronic hepatitis C for retreatment. GOALS: (1) To compare the performance of 10 biomarkers of fibrosis, including patented tests, among patients with chronic hepatitis C and treatment failure; and (2) to assess the impact on biomarker performance of using 2 different assays of hyaluronic acid (HA). STUDY: For 80 patients, liver histology (Metavir) was compared with biomarker scores using sera obtained within 6 months of liver biopsy (indirect biomarkers: AST:ALT ratio, APRI, Forns index, FIB-4, Fibrometer V3G; direct biomarkers: ELF, Fibrospect II, Hyaluronic acid-HA, Fibrometer V2G, Hepascore). Direct biomarker scores were calculated using 2 validated assays for HA (ELISA and radiometric). RESULTS: Using the ELISA assay for HA to calculate the direct panels, all 10 of the biomarkers exhibited comparable overall discriminatory performance (unweighted Obuchowski measure, ordROC 0.92-0.94, P-value>0.05) except AST:ALT ratio and APRI (ordROC 0.86-0.88, P-value<0.05). For the detection of moderate (F2-4) and advanced (F3-4) fibrosis, the AUROC of Fibrometer 2G were significantly higher than AST:ALT ratio and APRI but none of the other biomarkers. Good correlation was observed between the 2 HA assays (intraclass correlation coefficient=0.873) with the ELISA assay exhibiting superior diagnostic performance (ordROC 0.92 vs. 0.88, P-value=0.003). Importantly, the performance of many of the direct biomarkers at their diagnostic thresholds was heavily influenced by the choice of HA assay. CONCLUSIONS: Although many biomarkers exhibited good diagnostic performance for the detection of advancing fibrosis, our results indicate that diagnostic performance may be significantly affected by the selection of individual component assays.


Assuntos
Biomarcadores/sangue , Hepatite C Crônica , Ácido Hialurônico/sangue , Cirrose Hepática/sangue , Adolescente , Adulto , Idoso , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Adulto Jovem
15.
Euro Surveill ; 22(8)2017 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-28251889

RESUMO

We report the molecular investigations of a large influenza A(H3N2) outbreak, in a season characterised by sharp increase in influenza admissions since December 2016. Analysis of haemagglutinin (HA) sequences demonstrated co-circulation of multiple clades (3C.3a, 3C.2a and 3C.2a1). Most variants fell into a novel subclade (proposed as 3C.2a2); they possessed four unique amino acid substitutions in the HA protein and loss of a potential glycosylation site. These changes potentially modify the H3N2 strain antigenicity.


Assuntos
Doenças Transmissíveis Emergentes/genética , Epidemias , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Hemaglutininas/genética , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Substituição de Aminoácidos , Criança , Pré-Escolar , Doenças Transmissíveis Emergentes/epidemiologia , Feminino , Deriva Genética , Variação Genética , Glicosilação , Humanos , Lactente , Recém-Nascido , Vírus da Influenza A Subtipo H3N2/classificação , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/diagnóstico , Influenza Humana/virologia , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , Análise de Sequência de DNA , Adulto Jovem
16.
J Clin Microbiol ; 54(2): 392-400, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26659206

RESUMO

Digital PCR (dPCR) is being increasingly used for the quantification of sequence variations, including single nucleotide polymorphisms (SNPs), due to its high accuracy and precision in comparison with techniques such as quantitative PCR (qPCR) and melt curve analysis. To develop and evaluate dPCR for SNP detection using DNA, RNA, and clinical samples, an influenza virus model of resistance to oseltamivir (Tamiflu) was used. First, this study was able to recognize and reduce off-target amplification in dPCR quantification, thereby enabling technical sensitivities down to 0.1% SNP abundance at a range of template concentrations, a 50-fold improvement on the qPCR assay used routinely in the clinic. Second, a method was developed for determining the false-positive rate (background) signal. Finally, comparison of dPCR with qPCR results on clinical samples demonstrated the potential impact dPCR could have on clinical research and patient management by earlier (trace) detection of rare drug-resistant sequence variants. Ultimately this could reduce the quantity of ineffective drugs taken and facilitate early switching to alternative medication when available. In the short term such methods could advance our understanding of microbial dynamics and therapeutic responses in a range of infectious diseases such as HIV, viral hepatitis, and tuberculosis. Furthermore, the findings presented here are directly relevant to other diagnostic areas, such as the detection of rare SNPs in malignancy, monitoring of graft rejection, and fetal screening.


Assuntos
Antivirais/farmacologia , Farmacorresistência Viral , Vírus da Influenza A/efeitos dos fármacos , Vírus da Influenza A/genética , Influenza Humana/diagnóstico , Influenza Humana/virologia , Mutação , Antivirais/uso terapêutico , Genes Virais , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/tratamento farmacológico , Tipagem Molecular , Oseltamivir/farmacologia , Polimorfismo de Nucleotídeo Único , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade
17.
Conserv Biol ; 30(6): 1320-1329, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27113387

RESUMO

The variety of local animal sounds characterizes a landscape. We used ecoacoustics to noninvasively assess the species richness of various biotopes typical of an ecofriendly forest plantation with diverse ecological gradients and both nonnative and indigenous vegetation. The reference area was an adjacent large World Heritage Site protected area (PA). All sites were in a global biodiversity hotspot. Our results showed how taxa segregated into various biotopes. We identified 65 singing species, including birds, frogs, crickets, and katydids. Large, natural, protected grassland sites in the PA had the highest mean acoustic diversity (14.1 species/site). Areas covered in nonnative timber or grass species were devoid of acoustic species. Sites grazed by native and domestic megaherbivores were fairly rich (5.1) in acoustic species but none were unique to this habitat type, where acoustic diversity was greater than in intensively managed grassland sites (0.04). Natural vegetation patches inside the plantation mosaic supported high mean acoustic diversity (indigenous forests 7.6, grasslands 8.0, wetlands 9.1), which increased as plant heterogeneity and patch size increased. Indigenous forest patches within the plantation mosaic contained a highly characteristic acoustic species assemblage, emphasizing their complementary contribution to local biodiversity. Overall, acoustic signals determined spatial biodiversity patterns and can be a useful tool for guiding conservation.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Pradaria , Animais , Ecologia , Ecossistema
18.
Clin Infect Dis ; 60(6): 919-23, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25572898

RESUMO

Metagenomic next-generation sequencing (NGS) was used to diagnose an unusual and fatal case of progressive encephalitis in an immunocompromised adult presenting at disease onset as bilateral hearing loss. The sequencing and confirmatory studies revealed neuroinvasive infection of the brain by an astrovirus belonging to a recently discovered VA/HMO clade.


Assuntos
Infecções por Astroviridae/diagnóstico , Encefalite Viral/diagnóstico , Mamastrovirus/genética , Mamastrovirus/isolamento & purificação , Adulto , Encéfalo/patologia , Proteínas do Capsídeo/genética , Encefalite Viral/complicações , Evolução Fatal , Perda Auditiva Bilateral/etiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Leucemia Linfoide/complicações , Filogenia
19.
Clin Infect Dis ; 61(1): 120-8, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25778749

RESUMO

BACKGROUND: Emerging data relating to human immunodeficiency virus type 1 (HIV-1) cure suggest that vaccination to stimulate the host immune response, particularly cytotoxic cells, may be critical to clearing of reactivated HIV-1-infected cells. However, evidence for this approach in humans is lacking, and parameters required for a vaccine are unknown because opportunities to study HIV-1 reactivation are rare. METHODS: We present observations from a HIV-1 elite controller, not treated with combination antiretroviral therapy, who experienced viral reactivation following treatment for myeloma with melphalan and autologous stem cell transplantation. Mathematical modeling was performed using a standard viral dynamic model. Enzyme-linked immunospot, intracellular cytokine staining, and tetramer staining were performed on peripheral blood mononuclear cells; in vitro CD8 T-cell-mediated control of virion production by autologous CD4 T cells was quantified; and neutralizing antibody titers were measured. RESULTS: Viral rebound was measured at 28,000 copies/mL on day 13 post-transplant before rapid decay to <50 copies/mL in 2 distinct phases with t1/2 of 0.71 days and 4.1 days. These kinetics were consistent with an expansion of cytotoxic effector cells and killing of productively infected CD4 T cells. Following transplantation, innate immune cells, including natural killer cells, recovered with virus rebound. However, most striking was the expansion of highly functional HIV-1-specific cytotoxic CD8 T cells, at numbers consistent with those applied in modeling, as virus control was regained. CONCLUSIONS: These observations provide evidence that the human immune response is capable of controlling coordinated global HIV-1 reactivation, remarkably with potency equivalent to combination antiretroviral therapy. These data will inform design of vaccines for use in HIV-1 curative interventions.


Assuntos
Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , HIV-1/fisiologia , Ativação Viral/imunologia , Anticorpos Neutralizantes/sangue , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Citocinas/análise , ELISPOT , Anticorpos Anti-HIV/sangue , Infecções por HIV/complicações , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Melfalan/efeitos adversos , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Modelos Teóricos , Mieloma Múltiplo/tratamento farmacológico , Agonistas Mieloablativos/efeitos adversos , Agonistas Mieloablativos/uso terapêutico , Transplante de Células-Tronco/efeitos adversos , Subpopulações de Linfócitos T/imunologia , Transplante Autólogo
20.
Eur J Clin Invest ; 45(8): 888-94, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25995119

RESUMO

BACKGROUND: Hyponatraemia is a very common medical condition that is associated with multiple poor clinical outcomes and is often managed suboptimally because of inadequate assessment and investigation. Previously published guidelines for its management are often complex and impractical to follow in a hospital environment, where patients may present to divergent specialists, as well as to generalists. DESIGN: A group of senior, experienced UK clinicians, met to develop a practical algorithm for the assessment and management of hyponatraemia in a hospital setting. The latest evidence was discussed and reviewed in the light of current clinical practicalities to ensure an up-to-date perspective. An algorithm was largely developed following consensus opinion, followed up with subsequent additions and amendments that were agreed by all authors during several rounds of review. RESULTS: We present a practical algorithm which includes a breakdown of the best methods to evaluate volume status, simple assessments for the diagnosis of the various causes and a straightforward approach to treatment to minimise complexity and maximise patient safety. CONCLUSION: The algorithm we have developed reflects the best available evidence and extensive clinical experience and provides practical, useable guidance to improve patient care.


Assuntos
Algoritmos , Antibacterianos/uso terapêutico , Antagonistas dos Receptores de Hormônios Antidiuréticos/uso terapêutico , Benzazepinas/uso terapêutico , Demeclociclina/uso terapêutico , Hidratação , Hiponatremia/terapia , Síndrome de Secreção Inadequada de HAD/terapia , Hospitalização , Humanos , Hiponatremia/diagnóstico , Síndrome de Secreção Inadequada de HAD/diagnóstico , Guias de Prática Clínica como Assunto , Tolvaptan , Desequilíbrio Hidroeletrolítico/diagnóstico , Desequilíbrio Hidroeletrolítico/terapia
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