Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 75
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Ultrasound Obstet Gynecol ; 58(6): 864-874, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33942916

RESUMO

OBJECTIVES: To describe the prenatal neuroimaging spectrum of rhombencephalosynapsis (RES) and criteria for its classification according to the severity of vermian anomaly. METHODS: In this multicenter retrospective study of fetuses with RES between 2002 and 2020, the medical records and brain ultrasound and magnetic resonance images were evaluated comprehensively to determine the severity of the vermian anomaly and the presence of associated brain findings. RES was classified, according to the pattern of vermian agenesis and the extent of the fusion of the hemispheres, as complete RES (complete absence of the vermis) or partial RES (further classified according to the part of the vermis that was missing and, consequently, the region of hemispheric fusion, as anterior, posterior, severe or mixed RES). Findings were compared between cases with complete and those with partial RES. RESULTS: Included in the study were 62 fetuses with a gestational age ranging between 12 and 37 weeks. Most had complete absence of the vermis (complete RES, 77.4% of cases), a 'round-shaped' cerebellum on axial views (72.6%) and a transverse cerebellar diameter (TCD) < 3rd centile (87.1%). Among the 22.6% of cases with partial RES, 6.5% were classified as severe partial, 6.5% as partial anterior, 8.1% as partial mixed and 1.6% as partial posterior. Half of these cases presented with normal or nearly normal cerebellar morphology and 28.5% had a TCD within the normal limits. Infratentorially, the fourth ventricle was abnormal in 88.7% of cases overall, and anomalies of the midbrain and pons were frequent (93.5% and 77.4%, respectively). Ventriculomegaly was observed in 80.6% of all cases, being more severe in cases with complete RES than in those with partial RES, with high rates of parenchymal and septal disruption. CONCLUSIONS: This study provides prenatal neuroimaging criteria for the diagnosis and classification of RES, and identification of related features, using ultrasound and magnetic resonance imaging. According to our findings, a diagnosis of RES should be considered in fetuses with a small TCD (severe cerebellar hypoplasia) and/or a round-shaped cerebellum on axial views, during the second or third trimester, especially when associated with ventriculomegaly. Partial RES is more common than previously thought, but presents an extreme diagnostic challenge, especially in cases with normal or nearly-normal cerebellar morphobiometric features. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Vermis Cerebelar/anormalidades , Cerebelo/anormalidades , Anormalidades do Olho/diagnóstico por imagem , Doenças Renais Císticas/diagnóstico por imagem , Malformações do Sistema Nervoso/diagnóstico por imagem , Neuroimagem , Diagnóstico Pré-Natal/métodos , Retina/anormalidades , Rombencéfalo/anormalidades , Anormalidades Múltiplas/embriologia , Adulto , Vermis Cerebelar/diagnóstico por imagem , Vermis Cerebelar/embriologia , Cerebelo/diagnóstico por imagem , Cerebelo/embriologia , Anormalidades do Olho/embriologia , Feminino , Idade Gestacional , Humanos , Doenças Renais Císticas/embriologia , Imageamento por Ressonância Magnética , Imagem Multimodal , Malformações do Sistema Nervoso/embriologia , Gravidez , Retina/diagnóstico por imagem , Retina/embriologia , Estudos Retrospectivos , Rombencéfalo/diagnóstico por imagem , Rombencéfalo/embriologia , Índice de Gravidade de Doença , Ultrassonografia Pré-Natal
2.
Eur J Clin Microbiol Infect Dis ; 37(2): 227-232, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29063987

RESUMO

A chest infiltrate is needed to make a diagnosis of community-acquired pneumonia, but chest X-rays might be time consuming, entail radiation exposure, and demand resources that are not always available. We sought to derive a model to predict whether a patient will have an infiltrate on chest X-ray (CXR). This prospective observational study included patients visiting the Emergency Department of Beilinson Hospital in the years 2003-2004 (derivation cohort) and 2010-2011 (validation cohort), who had undergone a CXR, and were suspected of having a respiratory infection. We excluded all patients with possible healthcare associated infections. A logistic regression model was derived and applied to the validation cohort. A total of 1,555 patients met inclusion criteria: 993 in the derivation cohort and 562 in the validation cohort with 287 (29%) and 226 (40%) having an infiltrate, respectively. The derivation model area-under-the curve (AUC) was 0.79 (95% CI 0.76-0.82). We categorized the patients into three groups-presence or absence of infiltrate, or undetermined. In the validation cohort, 70 (12%) patients were classified as 'no infiltrate'; 3 (4%) of them had an infiltrate, 367 (65%) were classified as 'infiltrate'; 190 (52%) of them had an infiltrate on CXR, and 125 (46%) were classified as 'undetermined'; 33 (26%) of them with an infiltrate on CXR. Using this prediction model for the evaluation of patients with suspected respiratory infection in an ED setting may help avoid over 10% of CXRs.


Assuntos
Infecções Comunitárias Adquiridas/diagnóstico , Técnicas de Apoio para a Decisão , Infiltração de Neutrófilos/imunologia , Pneumonia/diagnóstico , Idoso , Infecções Comunitárias Adquiridas/diagnóstico por imagem , Infecções Comunitárias Adquiridas/microbiologia , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pneumonia/diagnóstico por imagem , Pneumonia/microbiologia , Estudos Prospectivos , Radiografia Torácica
3.
Exp Brain Res ; 235(2): 639-646, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27847986

RESUMO

Although spatial summation of pain (SSP) is central to the processing of pain intensity and quality, its mechanism is not fully understood. We previously found greater heat SSP in hairy than in glabrous skin, suggesting that perhaps A-mechano-heat II (AMH-II) nociceptors are the dominant subserving system. In order to further explore the role of A-delta fibers in heat-induced SSP, we analyzed the electrophysiological correlates of SSP under conditions that minimize the influence of skin thicknesses. Among 17 subjects, fast rate of rise (70 °C/sec) heat stimuli that induced a pre-fixed, similar, SSP magnitude for hairy and glabrous skin were repeatedly administered using large and small probes, during which time the contact heat-evoked potentials (CHEPs) and pain ratings were recorded. Both N2 and P2 amplitudes were larger in hairy than in glabrous skin, but a differential effect of SSP was found on the CHEPs. Despite similar psychophysical SSP in hairy and glabrous skin, the electrophysiological SSP reflected in N2 but not P2 amplitude was larger in hairy skin. Nevertheless, regardless of skin type, SSP was manifested by an increase in P2 amplitudes. Considering the uniform psychophysical SSP for the two skin types, the fast stimulation rate and lower activity of AMH-II in glabrous skin, a greater electrophysiological SSP in hairy than in glabrous skin may suggest that SSP is mainly subserved by AMH nociceptors. The overall SSP effect, manifested in greater P2 amplitude, may reflect specific brain responses aimed to prepare the individual to an increased potential tissue damage.


Assuntos
Temperatura Alta , Fibras Nervosas/fisiologia , Nociceptores/fisiologia , Limiar da Dor/fisiologia , Psicofísica , Adulto , Vias Aferentes/fisiologia , Potenciais Evocados/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Limiar da Dor/psicologia , Estimulação Física , Tempo de Reação/fisiologia , Pele/inervação , Escala Visual Analógica , Adulto Jovem
4.
Eur J Clin Microbiol Infect Dis ; 35(5): 779-84, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26864041

RESUMO

UNLABELLED: Several studies have shown an association between exposure to statins and favorable clinical outcomes for various types of infections. We aimed to assess the impact of statin use on mortality, disease severity and complications among hospitalized patients with Clostridium difficile infection (CDI). Data were analyzed from a retrospectively collected database of 499 patients diagnosed with CDI during 2009-2014. We compared infection outcomes between 178 statin (36 %) users and 321 (64 %) non-users. On multivariate analysis, we found that statin use did not have a significant impact on 30-day mortality (OR = 1.54; 95 % CI, 0.85-2.79; p = 0.15) or any significant effect on CDI severity and complication. Concomitant statin use has no significant impact on short-term mortality or effect on CDI severity and complications among hospitalized patients with CDI. However, patients in the statin group were older and had higher Charlson score compared with the non-statin group. Whether these factors affected a possible impact of statins on the disease course remains to be investigated. KEY MESSAGES: • Clostridium difficile is the most common cause of infectious nosocomial diarrhea among hospitalized adult patients in the developed countries. • There is an increasing morbidity and mortality of CDI patients due to the emergence of new strains of high virulence. • Recent studies demonstrated that prior statin use has protective and ameliorating effects on morbidity and mortality among CDI patients. • Our study showed that concomitant statin use has no significant impact on short-term mortality, CDI severity and its complications.


Assuntos
Clostridioides difficile/efeitos dos fármacos , Infecção Hospitalar , Enterocolite Pseudomembranosa/epidemiologia , Enterocolite Pseudomembranosa/microbiologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Estudos de Casos e Controles , Comorbidade , Enterocolite Pseudomembranosa/complicações , Enterocolite Pseudomembranosa/diagnóstico , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mortalidade , Avaliação de Resultados da Assistência ao Paciente , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
5.
Gynecol Endocrinol ; 32(9): 756-758, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27113862

RESUMO

OBJECTIVE: Pre-implantation genetic diagnosis (PGD) is required in order to screen and diagnose embryos of patients at risk of having a genetically affected offspring. A biopsy to diagnose the genetic profile of the embryo may be performed either before or after cryopreservation. The aim of this study was to determine which biopsy timing yields higher embryo survival rates. STUDY DESIGN: Retrospective cohort study of all PGD patients in a public IVF unit between 2010 and 2013. Inclusion criteria were patients with good-quality embryos available for cryopreservation by the slow freezing method. Embryos were divided into two groups: biopsy before and biopsy after cryopreservation. The primary outcome was embryo survival rates post thawing. RESULTS: Sixty-five patients met inclusion criteria. 145 embryos were biopsied before cryopreservation and 228 embryos were cryopreserved and biopsied after thawing. Embryo survival was significantly greater in the latter group (77% vs. 68%, p < 0.0001). CONCLUSION: Cryopreservation preceding biopsy results in better embryo survival compared to biopsy before cryopreservation.


Assuntos
Biópsia/normas , Criopreservação/normas , Transferência Embrionária/normas , Diagnóstico Pré-Implantação/normas , Técnicas de Reprodução Assistida/normas , Adulto , Feminino , Humanos , Estudos Retrospectivos , Fatores de Tempo
6.
Mult Scler ; 21(5): 562-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25432950

RESUMO

BACKGROUND: Neuronal loss following damage is often greater than expected from the severity of injury to the nerve itself. The visual pathways, which comprise a well-defined system, and optic neuritis (ON), which is usually a discrete event, make a fine model to study this phenomenon. OBJECTIVE: Understand the effect of focal optic nerve demyelination on neighboring white matter. METHODS: Diffusion tensor imaging and probabilistic tractography were used to identify and characterize the optic tracts and radiations of 17 ON and matched controls. Data were correlated with retinal nerve fiber layer (RNFL) thickness. RESULTS: Patients' optic tracts exhibited reduced axial diffusivity, which correlated with RNFL thickness values. Patients' optic radiations demonstrated intact axial diffusivity but reduced fractional anisotropy and elevated radial diffusivity, which could be explained by intra-bundle lesions. No correlations were found between diffusivity measurements in patients' optic tracts and radiations; or between RNFL thickness and optic radiations' diffusivity. CONCLUSIONS: Following ON, chronic axonal loss develops distally in the optic tracts, demonstrating Wallerian degeneration. Degeneration did not proceed to the optic radiations, opposing anterograde trans-neuronal changes. DTI in ON provides fine in-vivo human model for studying histological abnormalities in normal appearing white matter, localized in close proximity to damaged bundle.


Assuntos
Doenças Desmielinizantes/patologia , Neurite Óptica/patologia , Substância Branca/patologia , Adulto , Axônios/patologia , Estudos Transversais , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nervo Óptico/patologia , Sinapses/patologia , Degeneração Walleriana/patologia , Adulto Jovem
7.
Eur J Clin Microbiol Infect Dis ; 34(6): 1201-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25686730

RESUMO

Data on risk factors for Clostridium difficile infection (CDI) in diabetic patients are scarce. Recently, it has been shown that metformin increases the Bacteroidetes/Firmicutes ratio; therefore, it may yield a protective effect against CDI. We aimed to assess risk factors for CDI in diabetic patients beyond antibiotic treatment, and to determine the impact of metformin therapy on the development of CDI in these patients. In this retrospective, case-control study, all consecutive CDI diabetic patients, from January 2009 to December 2013, were included and compared to consecutive diabetic patients without CDI, hospitalized during the same period and in the same departments. Of 7,670 patients tested for C. difficile toxins, 486 were diabetics. Of them, 150 (30.8 %) were positive for C. difficile toxins and 336 (69.1 %) were negative. On multivariate analysis, metformin treatment was associated with a significant reduction in CDI [odds ratio (OR) = 0.58; 95 % confidence interval (CI), 0.37-0.93; p = 0.023], while heart failure was associated with significantly higher rates of CDI (OR = 1.654; 95 % CI, 1.007-2.716; p = 0.047), together with poor functional status, previous hospitalization, and abdominal surgery. Our findings suggest that, in diabetic patients, in addition to the well-recognized risk factors, heart failure is an additional risk factor for CDI, while metformin treatment seems to have a protective effect against the development of CDI. The exact mechanisms underlying this protective effect remain to be fully understood.


Assuntos
Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/epidemiologia , Complicações do Diabetes/epidemiologia , Diarreia/epidemiologia , Hipoglicemiantes/administração & dosagem , Metformina/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Infecções por Clostridium/induzido quimicamente , Diarreia/induzido quimicamente , Feminino , Insuficiência Cardíaca/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
8.
Neuroimage ; 103: 334-348, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25264227

RESUMO

We examined regional changes in brain volume in healthy adults (N=167, age 19-79years at baseline; N=90 at follow-up) over approximately two years. With latent change score models, we evaluated mean change and individual differences in rates of change in 10 anatomically-defined and manually-traced regions of interest (ROIs): lateral prefrontal cortex (LPFC), orbital frontal cortex (OF), prefrontal white matter (PFw), hippocampus (Hc), parahippocampal gyrus (PhG), caudate nucleus (Cd), putamen (Pt), insula (In), cerebellar hemispheres (CbH), and primary visual cortex (VC). Significant mean shrinkage was observed in the Hc, CbH, In, OF, and PhG, and individual differences in change were noted in all regions, except the OF. Pro-inflammatory genetic variants modified shrinkage in PhG and CbH. Carriers of two T alleles of interleukin-1ß (IL-1ß C-511T, rs16944) and a T allele of methylenetetrahydrofolate reductase (MTHFR C677T, rs1801133) polymorphisms showed increased PhG shrinkage. No effects of a pro-inflammatory polymorphism for C-reactive protein (CRP-286C>A>T, rs3091244) or apolipoprotein (APOE) ε4 allele were noted. These results replicate the pattern of brain shrinkage observed in previous studies, with a notable exception of the LPFC, thus casting doubt on the unique importance of prefrontal cortex in aging. Larger baseline volumes of CbH and In were associated with increased shrinkage, in conflict with the brain reserve hypothesis. Contrary to previous reports, we observed no significant linear effects of age and hypertension on regional brain shrinkage. Our findings warrant further investigation of the effects of neuroinflammation on structural brain change throughout the lifespan.


Assuntos
Envelhecimento/genética , Envelhecimento/patologia , Encéfalo/patologia , Individualidade , Inflamação/genética , Adulto , Idoso , Feminino , Genótipo , Humanos , Interpretação de Imagem Assistida por Computador , Inflamação/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Polimorfismo de Nucleotídeo Único , Adulto Jovem
9.
Eur J Clin Microbiol Infect Dis ; 32(12): 1511-6, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23754309

RESUMO

Neurosurgery is characterized by a prolonged risk period for surgical site infection (SSI), mainly related to the presence of cerebrospinal fluid (CSF) drains. We aimed to examine factors associated with post-neurosurgical SSIs, focusing on post-operative factors. A prospective cohort study was conducted in a single center over a period of 18 months in Israel. Included were adult patients undergoing clean or clean-contaminated craniotomy, including craniotomies with external CSF drainage or shunts. SSIs were defined by the Centers for Disease Control and Prevention (CDC) criteria for healthcare-associated infections. All patients were followed up for 90 days and those with foreign body insertion for 1 year. We compared patients with and without SSI. A multivariable regression analysis for SSI was conducted including uncorrelated variables significantly associated with SSI. A total of 502 patients were included, with 138 (27.5%) undergoing emergent or urgent craniotomy. The overall SSI rate was 5.6% (28 patients), of which 3.2% (16 patients) were intracerebral. Non-elective surgery, external CSF drainage/monitoring devices, re-operation, and post-operative respiratory failure were independently associated with subsequent SSI. External CSF devices was the only significant risk factor for intracerebral SSIs (p < 0.001). Internal shunts or other foreign body insertions were not associated with SSIs. A phenotypically identical isolate to that causing the SSI was isolated from respiratory secretions prior to the SSI in 4/9 patients with microbiologically documented intracerebral SSIs. Patients with SSIs had longer hospital stay, poorer functional capacity on discharge, and higher 90-day mortality. We raise the possibility of post-operative infection acquisition through external CSF devices. Standard operating procedures for their maintenance are necessary.


Assuntos
Craniotomia/efeitos adversos , Infecção da Ferida Cirúrgica/etiologia , Adulto , Idoso , Craniotomia/estatística & dados numéricos , Feminino , Humanos , Israel/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Fatores de Risco , Infecção da Ferida Cirúrgica/epidemiologia
10.
bioRxiv ; 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38076964

RESUMO

Inquiries into properties of brain structure and function have progressed due to developments in magnetic resonance imaging (MRI). To sustain progress in investigating and quantifying neuroanatomical details in vivo, the reliability and validity of brain measurements are paramount. Quality control (QC) is a set of procedures for mitigating errors and ensuring the validity and reliability of brain measurements. Despite its importance, there is little guidance on best QC practices and reporting procedures. The study of hippocampal subfields in vivo is a critical case for QC because of their small size, inter-dependent boundary definitions, and common artifacts in the MRI data used for subfield measurements. We addressed this gap by surveying the broader scientific community studying hippocampal subfields on their views and approaches to QC. We received responses from 37 investigators spanning 10 countries, covering different career stages, and studying both healthy and pathological development and aging. In this sample, 81% of researchers considered QC to be very important or important, and 19% viewed it as fairly important. Despite this, only 46% of researchers reported on their QC processes in prior publications. In many instances, lack of reporting appeared due to ambiguous guidance on relevant details and guidance for reporting, rather than absence of QC. Here, we provide recommendations for correcting errors to maximize reliability and minimize bias. We also summarize threats to segmentation accuracy, review common QC methods, and make recommendations for best practices and reporting in publications. Implementing the recommended QC practices will collectively improve inferences to the larger population, as well as have implications for clinical practice and public health.

11.
Neuroimage ; 55(3): 1287-97, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21232618

RESUMO

Advanced age is associated with declines in brain structure and in cognitive performance, but it is unclear which aspects of brain aging mediate cognitive declines. We inquired if individual differences in white matter integrity contribute to age differences in two cognitive domains with established vulnerability to aging: executive functioning and speed of processing. The participants were healthy volunteers aged 50-81, some of whom had elevated blood pressure, a known vascular risk factor. Using latent variable analyses, we examined whether age differences in regional white matter integrity mediated age-related differences in executive functions and speed of processing. Although diffusion-related latent variables showed stronger age differences than white matter volumes and white matter hyperintensity volumes, only one of them was significantly associated with cognitive performance. Smaller linear anisotropy partially mediated age-related reduction in speed of processing. The effect was significant in posterior (temporal-parietal-occipital) but not anterior (frontal) region, and appeared stronger for cognitive rather than reaction time measures of processing speed. The presence of hypertensive participants did not affect the results. We conclude that in healthy adults, deterioration of axonal integrity and ensuing breech of connectivity may underpin age-related slowing of information processing.


Assuntos
Envelhecimento/psicologia , Axônios/fisiologia , Encéfalo/citologia , Encéfalo/crescimento & desenvolvimento , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/fisiologia , Cognição/fisiologia , Imagem de Tensor de Difusão , Feminino , Humanos , Hipertensão/fisiopatologia , Hipertensão/psicologia , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Modelos Estruturais , Testes Neuropsicológicos , Caracteres Sexuais , Adulto Jovem
12.
Phys Chem Chem Phys ; 13(27): 12399-402, 2011 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-21660317

RESUMO

In this study we investigate salt effects on bundle formation of carbon nanotubes (CNTs) dispersed in an organic solvent, N-methyl-2-pyrrolidone (NMP). Addition of NaI salt leads to self-assembly of CNTs into well-recognizable bundles. It is possible to control the size of the CNT bundles by varying the salt concentration.

13.
Neuroimage ; 49(3): 2083-93, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19850136

RESUMO

We investigated differences associated with age and hypertension, a common risk factor for vascular disease, in three aspects of white matter integrity--gross regional volumes of the white matter, volume of the white matter hyperintensities (WMH) and diffusion properties. We acquired MRI scans on 93 adult volunteers (age 50-77 years; 36 with diagnosis of hypertension or elevated blood pressure), and obtained all measures in seven brain regions: frontal, temporal, parietal and occipital white matter, and the genu, body and splenium of the corpus callosum. The results demonstrated robust age-related differences in diffusion-based indices of cerebral white matter integrity and age-related increase in the WMH volume, but no age differences in the gross regional volumes of the white matter. Hypertension was associated with decline in fractional anisotropy, and exacerbated age differences in fractional anisotropy more than those in the volume of WMH. These findings indicate that of all examined measures, diffusion-based indices of white matter integrity may be the most sensitive indicators of global and regional declines and vascular damage in the aging brain.


Assuntos
Envelhecimento/patologia , Encéfalo/patologia , Hipertensão/patologia , Fatores Etários , Idoso , Imagem de Tensor de Difusão , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade
14.
Clin Microbiol Infect ; 26(12): 1644-1650, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32213316

RESUMO

OBJECTIVES: The aim was to analyse the population pharmacokinetics of colistin and to explore the relationship between colistin exposure and time to death. METHODS: Patients included in the AIDA randomized controlled trial were treated with colistin for severe infections caused by carbapenem-resistant Gram-negative bacteria. All subjects received a 9 million units (MU) loading dose, followed by a 4.5 MU twice daily maintenance dose, with dose reduction if creatinine clearance (CrCL) < 50 mL/min. Individual colistin exposures were estimated from the developed population pharmacokinetic model and an optimized two-sample per patient sampling design. Time to death was evaluated in a parametric survival analysis. RESULTS: Out of 406 randomized patients, 349 contributed pharmacokinetic data. The median (90% range) colistin plasma concentration was 0.44 (0.14-1.59) mg/L at 15 minutes after the end of first infusion. In samples drawn 10 hr after a maintenance dose, concentrations were >2 mg/L in 94% (195/208) and 44% (38/87) of patients with CrCL ≤120 mL/min, and >120 mL/min, respectively. Colistin methanesulfonate sodium (CMS) and colistin clearances were strongly dependent on CrCL. High colistin exposure to MIC ratio was associated with increased hazard of death in the multivariate analysis (adjusted hazard ratio (95% CI): 1.07 (1.03-1.12)). Other significant predictors included SOFA score at baseline (HR 1.24 (1.19-1.30) per score increase), age and Acinetobacter or Pseudomonas as index pathogen. DISCUSSION: The population pharmacokinetic model predicted that >90% of the patients had colistin concentrations >2 mg/L at steady state, but only 66% at 4 hr after start of treatment. High colistin exposure was associated with poor kidney function, and was not related to a prolonged survival.


Assuntos
Antibacterianos/farmacocinética , Colistina/farmacocinética , Farmacorresistência Bacteriana , Infecções por Bactérias Gram-Negativas/mortalidade , Antibacterianos/sangue , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Carbapenêmicos/farmacologia , Colistina/sangue , Colistina/farmacologia , Colistina/uso terapêutico , Estado Terminal , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos
15.
Clin Microbiol Infect ; 25(3): 280-289, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30472427

RESUMO

OBJECTIVES: The pleiotropic effect of hydroxymethylglutaryl-CoA reductase inhibitors (statins) might have a beneficial effect in sepsis through several mechanisms. The aim was to assess the efficacy and safety of statins, compared with placebo, for the treatment of sepsis in adults. METHODS: We searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, 2017, Issue 12), OVID MEDLINE (from 1966 to January 2018), Embase (Ovid SP, from 1974 to January 2018), and LILACS (from 1986 to January 2018). We also searched the trial registries ISRCTN and ClinicalTrials.gov to January 2018. The eligibility criteria were randomized controlled trials comparing the treatment of statins versus placebo in adult patients who were hospitalized due to sepsis. Participants were adults (16 years and older) hospitalized because of sepsis or who developed sepsis during admission. Interventions were treatment with hydroxymethylglutaryl-CoA reductase inhibitors (statins) versus no treatment or placebo. We performed a systematic review of all randomized controlled trials published until January 2018, assessing the efficacy and safety of statins in sepsis treatment. Two primary outcomes were assessed: 30-day overall mortality and deterioration to severe sepsis during management. Secondary outcomes were hospital mortality, need for mechanical ventilation and drug related adverse events. RESULTS: Fourteen trials evaluating 2628 patients were included. Statins did not reduce 30-day all-cause mortality neither in all patients (risk ratio (RR) 0.96, 95% confidence interval (CI) 0.83-1.10), nor in a subgroup of patients with severe sepsis (RR 0.97, 95% CI 0.84-1.12). The certainty of evidence for both outcomes was high. There was no change in the rate of adverse events between study arms (RR 1.24, 95% CI 0.94 to 1.63). The certainty of evidence for this outcome was high. CONCLUSIONS: The use of statin therapy in adults for the indication of sepsis is not recommended.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Sepse/tratamento farmacológico , Adulto , Estudos de Avaliação como Assunto , Humanos , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto , Sepse/mortalidade , Falha de Tratamento
16.
Clin Microbiol Infect ; 25(6): 711-716, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30291971

RESUMO

OBJECTIVES: The rise in carbapenem resistance among Gram-negative bacteria has renewed interest in colistin. Recently, the EUCAST-CLSI Polymyxin Breakpoints Working Group declared that broth microdilution (BMD) is the only valid method for colistin susceptibility testing. BMD is not easily incorporated into the routine work of clinical laboratories, and usually this test is incorporated serially, resulting in delayed susceptibility reporting. We tested a strategy of combining VITEK® 2 with a 2 µg/mL colistin agar dilution (VITEK® 2/AD) screening plate to improve performance and time to reporting of colistin susceptibility. METHODS: Colistin susceptibility for 364 clinical isolates was determined by VITEK® 2/AD and compared with the reference standard BMD according to the ISO 20776-1:2007 and CLSI guidelines. The EUCAST colistin susceptibility breakpoint of ≤2 µg/mL was used. Escherichia coli NCTC 13846 served as quality control strain. Agreement, very major error (VME) and major error rates were determined using ISO 20776-2:2007. RESULTS: The VME rate for VITEK® 2 alone was 30.6% (15/49, 95% CI 18.3-45.4%), and was reduced to 10.2% (5/49, 95% CI 3.4-22.2%) using the VITEK® 2/AD combined testing. The combined testing had categorical agreement with BMD of 97% (354/364, 95% CI 95.0-98.7%), and a major error (ME) rate of 1.6% (5/315, 95% CI 0.5-3.7%). Using the combined testing, even against challenging strains, 349 (95.8%, 95% CI 93.3-97.7%) colistin susceptibility results could be reported, and only 15 isolates required further analysis by BMD. DISCUSSION: Our method is simple to apply and allows rapid reporting of colistin susceptibility.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Programas de Rastreamento/métodos , Testes de Sensibilidade Microbiana/métodos , Ágar , Meios de Cultura , Humanos , Fatores de Tempo
17.
Infect Drug Resist ; 11: 2571-2581, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30588040

RESUMO

PURPOSE: Complicated urinary tract infections (cUTIs) are among the most frequent health-care-associated infections. In patients with cUTI, Pseudomonas aeruginosa deserves special attention, since it can affect patients with serious underlying conditions. Our aim was to gain insight into the risk factors and prognosis of P. aeruginosa cUTIs in a scenario of increasing multidrug resistance (MDR). METHODS: This was a multinational, retrospective, observational study at 20 hospitals in south and southeastern Europe, Turkey, and Israel including consecutive patients with cUTI hospitalized between January 2013 and December 2014. A mixed-effect logistic regression model was performed to assess risk factors for P. aeruginosa and MDR P. aeruginosa cUTI. RESULTS: Of 1,007 episodes of cUTI, 97 (9.6%) were due to P. aeruginosa. Resistance rates of P. aeruginosa were: antipseudomonal cephalosporins 35 of 97 (36.1%), aminoglycosides 30 of 97 (30.9%), piperacillin-tazobactam 21 of 97 (21.6%), fluoroquinolones 43 of 97 (44.3%), and carbapenems 28 of 97 (28.8%). The MDR rate was 28 of 97 (28.8%). Independent risk factors for P. aeruginosa cUTI were male sex (OR 2.61, 95% CI 1.60-4.27), steroid therapy (OR 2.40, 95% CI 1.10-5.27), bedridden functional status (OR 1.79, 95% CI 0.99-3.25), antibiotic treatment within the previous 30 days (OR 2.34, 95% CI 1.38-3.94), indwelling urinary catheter (OR 2.41, 95% CI 1.43-4.08), and procedures that anatomically modified the urinary tract (OR 2.01, 95% CI 1.04-3.87). Independent risk factors for MDR P. aeruginosa cUTI were age (OR 0.96, 95% CI 0.93-0.99) and anatomical urinary tract modification (OR 4.75, 95% CI 1.06-21.26). Readmission was higher in P. aeruginosa cUTI patients than in other etiologies (23 of 97 [23.7%] vs 144 of 910 [15.8%], P=0.04), while 30-day mortality was not significantly different (seven of 97 [7.2%] vs 77 of 910 [8.5%], P=0.6). CONCLUSION: Patients with P. aeruginosa cUTI had characteristically a serious baseline condition and manipulation of the urinary tract, although their mortality was not higher than that of patients with cUTI caused by other etiologies.

18.
AJNR Am J Neuroradiol ; 38(8): 1617-1622, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28546249

RESUMO

BACKGROUND AND PURPOSE: To date, research on extracranial venous collaterals has been focused on structure, with relatively little attention paid to hemodynamics. We addressed this limitation by quantitatively comparing collateral flow in patients with multiple sclerosis and healthy controls by using phase-contrast MR imaging. We hypothesize that patients with MS with structurally anomalous internal jugular veins will have elevated collateral venous flow compared with healthy controls. MATERIALS AND METHODS: The sample consisted of 276 patients with MS and 106 healthy controls. We used MRV to classify internal jugular veins as stenotic and nonstenotic based on an absolute cross-sectional area threshold in 276 patients with MS and 60 healthy controls; 46 healthy controls lacked this imaging. Individual and total vessel flows were quantified by using phase-contrast MR imaging on all patients. Veins were classified by extracranial drainage type: internal jugular veins (I), paraspinal (II), and superficial (III). Differences among healthy controls, patients with MS, nonstenotic patients, and stenotic subgroups in total venous flow by vessel type were evaluated in a general linear model for statistical analysis. RESULTS: In the MS group, 153 patients (55%) evidenced stenosis, whereas 12 (20%) healthy controls were classified as stenotic (P < .001). Compared with healthy controls, the MS group showed lower type I flow and increased type II flow. Stenosis was associated with reduced flow in the type I vessels [F(1272) = 68; P < .001]. The stenotic MS group had increased flow in the type II vessels compared with the nonstenotic MS group [F(1272) = 67; P < .001]. CONCLUSIONS: Compared with healthy controls, patients with MS exhibit reduced venous flow in the main extracerebral drainage vein (internal jugular vein). In contrast, flow in the paraspinal venous collaterals is elevated in patients with MS and exacerbated by venous stenosis. Collateral drainage may be a compensatory response to internal jugular vein flow reduction.


Assuntos
Circulação Colateral , Veias Jugulares/diagnóstico por imagem , Esclerose Múltipla/diagnóstico por imagem , Adulto , Idoso , Anatomia Transversal , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/fisiopatologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Veias Jugulares/patologia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Insuficiência Venosa/complicações , Insuficiência Venosa/diagnóstico por imagem
19.
Artigo em Inglês | MEDLINE | ID: mdl-16766342

RESUMO

Visuospatial attention has been shown to be robust to the effects of increasing age. Nonetheless, models linking individual differences in working memory capacity to attentional performance suggest that older adults may experience disruptions in visuospatial attention under conditions of resource load. Two experiments were conducted to investigate the effects of age and concurrent working memory load on two tasks that have been proposed to require posterior attentional processes. The findings suggest that loading working memory resources selectively disrupts performance on a nonintegrated Stroop task, whereas cue utilization remains intact. In addition, imposing a working memory load delays the deployment of visuospatial attention in both experiments. Regarding the effects of age, findings suggest that older adults can effectively perform both attentional tasks despite working memory load. Age differences did emerge in the time course of cue utilization. Findings point to the resilience of visuospatial attention in aging, even under conditions of significant cognitive load. We discuss these results and their implications for models postulating a role for working memory capacity in attentional behaviors.


Assuntos
Envelhecimento/fisiologia , Atenção/fisiologia , Memória de Curto Prazo/fisiologia , Percepção Espacial/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/estatística & dados numéricos , Tempo de Reação/fisiologia , Reprodutibilidade dos Testes , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA