49 research outputs found
Lipid-lowering pretreatment and outcome following intravenous thrombolysis for acute ischaemic stroke: a post hoc analysis of the enhanced control of hypertension and thrombolysis stroke study trial
Background: Debate exists as to whether statin pretreatment confers an increased risk of 90-day mortality and symptomatic intracranial haemorrhage (sICH) in acute ischaemic stroke (AIS) patients treated with intravenous thrombolysis. We assessed the effects of undifferentiated lipid-lowering pretreatment on outcomes and interaction with low-dose versus standard-dose alteplase in a post hoc subgroup analysis of the Enhanced Control of Hypertension and Thrombolysis Stroke Study.
Methods: In all, 3,284 thrombolysis-eligible AIS patients (mean age 66.6 years; 38% women), with information on lipid-lowering pretreatment, were randomly assigned to low-dose (0.6 mg/kg) or standard-dose (0.9 mg/kg) intravenous alteplase within 4.5 h of symptom onset. Of the total number of patients, 615 (19%) received statin or other lipid-lowering pretreatment. The primary clinical outcome was combined endpoint of death or disability (modified Rankin Scale scores 2–6) at 90 days.
Results: Compared with patients with no lipid-lowering pretreatment, those with lipid-lowering pretreatment were significantly older, more likely to be non-Asian and more likely to have a medical history including vascular co-morbidity. After propensity analysis assessment and adjustment for important baseline variables at the time of randomisation, as well as imbalances in management during the first 7 days of hospital admission, there were no significant differences in mortality (OR 0.85; 95% CI 0.58–1.25, p = 0.42), or in overall 90-day death and disability (OR 0.85, 95% CI 0.67–1.09, p = 0.19), despite a significant decrease in sICH among those with lipid-lowering pretreatment according to the European Co-operative Acute Stroke Study 2 definition (OR 0.49, 95% CI 0.28–0.83, p = 0.009). No differences in key efficacy or safety outcomes were seen in patients with and without lipid-lowering pretreatment between low- and standard-dose alteplase arms.
Conclusions: Lipid-lowering pretreatment is not associated with adverse outcome in AIS patients treated with intravenous alteplase, whether assessed by 90-day death and disability or death alone
Co-production of hydrogen and ethanol from glucose in Escherichia coli by activation of pentose-phosphate pathway through deletion of phosphoglucose isomerase (pgi) and overexpression of glucose-6-phosphate dehydrogenase (zwf) and 6-phosphogluconate dehydrogenase (gnd)
Background: Biologically, hydrogen (H-2) can be produced through dark fermentation and photofermentation. Dark fermentation is fast in rate and simple in reactor design, but H-2 production yield is unsatisfactorily low as < 4 mol H-2/ mol glucose. To address this challenge, simultaneous production of H-2 and ethanol has been suggested. Co-production of ethanol andH(2) requires enhanced formation of NAD(P) H during catabolism of glucose, which can be accomplished by diversion of glycolytic flux from the Embden-Meyerh-of-Parnas (EMP) pathway to the pentose-phosphate (PP) pathway in Escherichia coli. However, the disruption of pgi (phosphoglucose isomerase) for complete diversion of carbon flux to the PP pathway made E. coli unable to grow on glucose under anaerobic condition. Results: Here, we demonstrate that, when glucose-6-phosphate dehydrogenase (Zwf) and 6-phosphogluconate dehydrogenase (Gnd), two major enzymes of the PP pathway, are homologously overexpressed, E. coli.pgi can recover its anaerobic growth capability on glucose. Further, with additional deletions of Delta hycA,Delta hyaAB,Delta hybBC,Delta ldhA, and Delta frdAB, the recombinant.pgi mutant could produce 1.69 mol H-2 and 1.50 mol ethanol from 1 mol glucose. However, acetate was produced at 0.18 mol mol(-1) glucose, indicating that some carbon is metabolized through the Entner-Doudoroff (ED) pathway. To further improve the flux via the PP pathway, heterologous zwf and gnd from Leuconostoc mesenteroides and Gluconobacter oxydans, respectively, which are less inhibited by NADPH, were overexpressed. The new recombinant produced more ethanol at 1.62 mol mol(-1) glucose along with 1.74 mol H-2 mol(-1) glucose, which are close to the theoretically maximal yields, 1.67 mol mol(-1) each for ethanol andH(2). However, the attempt to delete the ED pathway in the.pgi mutant to operate the PP pathway as the sole glycolytic route, was unsuccessful. Conclusions: By deletion of pgi and overexpression of heterologous zwf and gnd in E. coli Delta hycA Delta hyaAB Delta hybBC Delta ldhA Delta frdAB, two important biofuels, ethanol andH(2), could be successfully co-produced at high yields close to their theoretical maximums. The strains developed in this study should be applicable for the production of other biofuels and biochemicals, which requires supply of excessive reducing power under anaerobic conditions
Investigating Population Genetic Structure in a Highly Mobile Marine Organism: The Minke Whale Balaenoptera acutorostrata acutorostrata in the North East Atlantic
Inferring the number of genetically distinct populations and their levels of connectivity is of key importance for the sustainable management and conservation of wildlife. This represents an extra challenge in the marine environment where there are few physical barriers to gene-flow, and populations may overlap in time and space. Several studies have investigated the population genetic structure within the North Atlantic minke whale with contrasting results. In order to address this issue, we analyzed ten microsatellite loci and 331 bp of the mitochondrial D-loop on 2990 whales sampled in the North East Atlantic in the period 2004 and 2007–2011. The primary findings were: (1) No spatial or temporal genetic differentiations were observed for either class of genetic marker. (2) mtDNA identified three distinct mitochondrial lineages without any underlying geographical pattern. (3) Nuclear markers showed evidence of a single panmictic population in the NE Atlantic according STRUCTURE's highest average likelihood found at K = 1. (4) When K = 2 was accepted, based on the Evanno's test, whales were divided into two more or less equally sized groups that showed significant genetic differentiation between them but without any sign of underlying geographic pattern. However, mtDNA for these individuals did not corroborate the differentiation. (5) In order to further evaluate the potential for cryptic structuring, a set of 100 in silico generated panmictic populations was examined using the same procedures as above showing genetic differentiation between two artificially divided groups, similar to the aforementioned observations. This demonstrates that clustering methods may spuriously reveal cryptic genetic structure. Based upon these data, we find no evidence to support the existence of spatial or cryptic population genetic structure of minke whales within the NE Atlantic. However, in order to conclusively evaluate population structure within this highly mobile species, more markers will be required
Higroma quístico retronucal como marcador de anomalías cromosómicas en el primer trimestre de la gestación
Background: Nuchal cystic hygroma is the most frequently identified marker of chromosomal anomalies during first trimester screening. Objective: To determine the association of the nuchal cystic hygroma with chromosomal anomalies diagnosed with karyotyping done between the first and second trimesters of pregnancy. Design: Retrospective study. Setting: Instituto Latinoamericano de Salud Reproductiva (ILSAR), Lima, Peru. Patients. Fetuses with nuchal cystic hygroma. Methods: The data were obtained from the ILSAR database between August 2007 and May 2018, the cases diagnosed by ultrasound from week 11 to 13.6. Nuchal cystic hygroma was defined as the presence of septated liquid content in the nuchal axial section with a thickness above the 95th percentile value for increased nuchal translucency value for the crown-rump length. The karyotype was obtained between the first and second trimesters from material collected by chorionic villus sampling (BVS) or amniocentesis (AMC). Main outcome measures: Karyotyping results were compared between cases with cystic hygroma alone and cases with cystic hygroma in addition to another marker. Results: Out of 459 invasive procedures performed in fetuses with high risk for chromosomal anomalies based on the Fetal test database of Spain, there were 162 cases of chromosomal anomalies (35.3%), and 104 cases of nuchal cystic hygroma (22.7%). Nuchal cystic hygroma was associated with a higher frequency of chromosomal abnormalities, compared to fetuses without cystic hygroma (52.9% vs. 30.1%; p<0.001). Out of 61 cases of hygroma alone, 42.3% had chromosomal anomalies, and when the hygroma was associated with other markers (fetal hydrops, abnormal ductus venosus, heart disease), 65.1% had chromosomal abnormalities. There was a statistically significant difference (p=0.003) for the presence of monosomy X between the group with cystic hygroma alone and the group with hygroma and fetal hydrops. There was no difference in hygroma thickness between the groups with and without chromosomal abnormalities. Conclusions: Nuchal cystic hygroma is a risk marker with high predictive value for chromosomal abnormalities, and its identification during prenatal screening may be considered an indication to a diagnostic test. When cystic hygroma is associated to flow abnormalities of the ductus venosus or fetal hydrops, chromosomal abnormalities significantly increase. The hygroma associated with hydrops was primarily linked to monosomy X, while the hygroma associated with abnormal flow velocity waveforms of the ductus venosus was linked to trisomy 21.Antecedentes. El higroma quístico retronucal es el marcador de anomalías cromosómicas identificado con mayor frecuencia en el tamizaje del primer trimestre. Objetivo. Evaluar la asociación del higroma quístico retronucal y anomalías cromosómicas diagnosticadas con el cariotipo, entre el primer y segundo trimestre del embarazo. Diseño. Estudio retrospectivo. Institución. Instituto Latinoamericano de Salud Reproductiva (ILSAR), Lima, Perú. Pacientes. Fetos con higroma quístico retronucal. Método. Estudio de fetos con higroma quístico retronucal, obtenidos de la base de datos de ILSAR, entre agosto del 2007 y mayo del 2018, diagnosticados por ecografía entre las 11 y 13,6 semanas. El higroma quístico retronucal se definió como la presencia de contenido líquido tabicado en el corte axial retronucal con un grosor mayor al percentil 95 del valor de translucencia nucal aumentada para la longitud corona-nalga. Se obtuvo el cariotipo entre el primer y segundo trimestre en material obtenido por biopsia de vellosidades coriales (BVC) o amniocentesis (AMC). Principales medidas de resultados. Los resultados del cariotipo fueron comparados entre los casos de higroma quístico solo y los casos que tuvieron higroma y adicionalmente otro marcador. Resultados. De un total de 459 procedimientos invasivos realizados en fetos con alto riesgo para anomalías cromosómicas en base al Fetal test de España, hubieron 162 casos de anomalías cromosómicas (35,3%) y se identificó 104 casos de higroma quístico retronucal (22s7%). El hallazgo de higroma quístico retronucal se asoció con mayor presencia de anomalías cromosómicas, comparado con los fetos sin higroma quístico (52,9% vs. 30,1%; p<0,001). De 61 casos de higroma solo, 42,3% tenían anomalía cromosómica, y cuando el higroma estaba asociado a otros marcadores (hidrops fetal, ductus venoso anormal, cardiopatía, ausencia de hueso nasal), hubo 65,1% de anomalías cromosómicas. Hubo diferencia estadística significativa (p=0,003) para la presencia de monosomía X, entre el grupo con higroma solo y el de higroma + hidrops fetal. No hubo diferencia en el grosor del higroma entre el grupo con y sin anomalía cromosómica. Conclusiones. El higroma quístico retronucal es un marcador de riesgo con alto valor predictivo para anomalías cromosómicas. Su identificación en el tamizaje prenatal podría ser indicación para recomendar una prueba diagnóstica. Cuando se asocia a anormalidad del flujo del ductus venoso o hidrops fetal, aumentan significativamente las anomalías cromosómicas. El higroma asociado conhidrops se vinculó mayoritariamente a la monosomía X, mientras que el higroma asociado con onda de velocidad de flujo-OVF de ductus venoso anormal a la trisomía 21
Sex differences in clinical characteristics and outcome after stroke: the HeadPoST trial
Resumen de la ponencia presentada al: 27th Annual Scientific Meeting of the Stroke Society of Australasia 23 – 25 August 2017. Queenstown, New Zealan
Low-Dose versus Standard-Dose Intravenous Alteplase in Acute Ischemic Stroke
BACKGROUND
Thrombolytic therapy for acute ischemic stroke with a lower-than-standard dose of intravenous alteplase may improve recovery along with a reduced risk of intracerebral hemorrhage.
METHODS
Using a 2-by-2 quasi-factorial open-label design, we randomly assigned 3310 patients who were eligible for thrombolytic therapy (median age, 67 years; 63% Asian) to low-dose intravenous alteplase (0.6 mg per kilogram of body weight) or the standard dose (0.9 mg per kilogram); patients underwent randomization within 4.5 hours after the onset of stroke. The primary objective was to determine whether the low dose would be noninferior to the standard dose with respect to the primary outcome of death or disability at 90 days, which was defined by scores of 2 to 6 on the modified Rankin scale (range, 0 [no symptoms] to 6 [death]). Secondary objectives were to determine whether the low dose would be superior to the standard dose with respect to centrally adjudicated symptomatic intracerebral hemorrhage and whether the low dose would be noninferior in an ordinal analysis of modified Rankin scale scores (testing for an improvement in the distribution of scores). The trial included 935 patients who were also randomly assigned to intensive or guideline-recommended blood-pressure control.
RESULTS
The primary outcome occurred in 855 of 1607 participants (53.2%) in the low-dose group and in 817 of 1599 participants (51.1%) in the standard-dose group (odds ratio, 1.09; 95% confidence interval [CI], 0.95 to 1.25; the upper boundary exceeded the noninferiority margin of 1.14; P=0.51 for noninferiority). Low-dose alteplase was noninferior in the ordinal analysis of modified Rankin scale scores (unadjusted common odds ratio, 1.00; 95% CI, 0.89 to 1.13; P=0.04 for noninferiority). Major symptomatic intracerebral hemorrhage occurred in 1.0% of the participants in the low-dose group and in 2.1% of the participants in the standard-dose group (P=0.01); fatal events occurred within 7 days in 0.5% and 1.5%, respectively (P=0.01). Mortality at 90 days did not differ significantly between the two groups (8.5% and 10.3%, respectively; P=0.07).
CONCLUSIONS
This trial involving predominantly Asian patients with acute ischemic stroke did not show the noninferiority of low-dose alteplase to standard-dose alteplase with respect to death and disability at 90 days. There were significantly fewer symptomatic intracerebral hemorrhages with low-dose alteplase
'I always have the idea of sin in my mind...': family of origin, religion, and Chilean young gay men
This research aimed to explore the influences of family's values and religiosity on the sexual identity life course of Chilean young gay men. Volunteer participants were recruited through invitations published by two sexual minority organizations based in Santiago. Six same-sex-attracted Chilean men between 18 and 24 years old were interviewed using a semi-structured interview. Foucauldian discourse analysis was used to explore how discourses about their sexual identity development were constructed, including the implications for subjectivity and the location of these compressions within a social and historical context. Findings revealed feelings of self-rejection and self-recrimination featured in the life course development of participants’ sexual identities that were embedded within the familiar and sociohistorical context in which they lived. In particular, parents’ religious beliefs regarding the abnormal and unnatural view of “homosexuality” shaped by Catholic and Evangelical churches played a crucial role in lack of acceptance during their development. The study showed the internal struggle faced by these Chilean young gay men to achieve their own acceptance and perceived normalization of their sexual orientation. Implications for therapy and education with young gay men living in a predominantly Christian cultural context and Latino countries are reviewed
Dysphagia screening and risks of pneumonia and adverse outcomes after acute stroke: An international multicenter study.
BACKGROUND:Dysphagia is associated with aspiration pneumonia after stroke. Data are limited on the influences of dysphagia screen and assessment in clinical practice. AIMS:To determine associations between a "brief" screen and "detailed" assessment of dysphagia on clinical outcomes in acute stroke patients. METHODS:A prospective cohort study analyzed retrospectively using data from a multicenter, cluster cross-over, randomized controlled trial (Head Positioning in Acute Stroke Trial [HeadPoST]) from 114 hospitals in nine countries. HeadPoST included 11,093 acute stroke patients randomized to lying-flat or sitting-up head positioning. Herein, we report predefined secondary analyses of the association of dysphagia screening and assessment and clinical outcomes of pneumonia and death or disability (modified Rankin scale 3-6) at 90 days. RESULTS:Overall, 8784 (79.2%) and 3917 (35.3%) patients were screened and assessed for dysphagia, respectively, but the frequency and timing for each varied widely across regions. Neither use of a screen nor an assessment for dysphagia was associated with the outcomes, but their results were compared to "screen-pass" patients, those who failed had higher risks of pneumonia (adjusted odds ratio [aOR] = 3.00, 95% confidence interval [CI] = 2.18-4.10) and death or disability (aOR = 1.66, 95% CI = 1.41-1.95). Similar results were evidence for the results of an assessment for dysphagia. Subsequent feeding restrictions were related to higher risk of pneumonia in patients failed dysphagia screen or assessment (aOR = 4.06, 95% CI = 1.72-9.54). CONCLUSIONS:Failing a dysphagia screen is associated with increased risks of pneumonia and poor clinical outcome after acute stroke. Further studies concentrate on determining the effective subsequent feeding actions are needed to improve patient outcomes
Rationale, design, and progress of the ENhanced Control of Hypertension ANd Thrombolysis strokE stuDy (ENCHANTED) trial: An international multicenter 2×2 quasi-factorial randomized controlled trial of low- vs. standard-dose rt-PA and early intensive vs. g
© 2015 World Stroke Organization. Rationale: Controversy exists over the optimal dose of intravenous (iv) recombinant tissue plasminogen activator (rt-PA) and degree of blood pressure (BP) control in acute ischaemic stroke (AIS). Asian studies suggest low-dose (0·6mg/kg) is more efficacious than standard-dose (0·9mg/kg) iv rt-PA, and guidelines recommend reducing systolic BP to <185mmHg before and <180mmHg after use of iv rt-PA, despite observational studies indicating better outcomes at much lower (<140mmHg) systolic BP levels in this patient group. Aims: The study aims to assess in thrombolysis-eligible AIS patients whether: (i) low-dose (0·6mg/kg body weight; maximum 60mg) iv rt-PA has non-inferior efficacy and lower risk of symptomatic intracerebral haemorrhage (sICH) compared to standard-dose (0·9mg/kg body weight; maximum 90mg) iv rt-PA; and (ii) early intensive BP lowering (systolic target 130-140mmHg) has superior efficacy and lower risk of any ICH compared to guideline-recomm