Acute extracranial occlusion of the internal carotid artery: emergent surgery remains a viable option

Background

Acute symptomatic occlusion of extracranial internal carotid artery (eICA) can lead to a critical and potentially devastating stroke associated with high morbidity and mortality. Optimal treatment remains unclear. We analyzed our institutional experience with emergent surgical recanalization of acutely occluded eICA.

Methods

Retrospective analysis of hospital records, surgical reports, imaging studies and outpatient records. Final outcome was assessed according to modified Rankin Scale (mRS).

Results

Between January 2010 and September 2013, 22 patients underwent emergent surgical recanalization. There were 17 men and five women, mean age 65.4 years (range 37–85). Mean admission National Institute of Health Stroke Scale (NIHSS) was 12 (range 6–21). All patients had evidence of salvageable penumbra on perfusion computed tomography. Tandem intracranial lesion was present in nine patients. Surgical recanalization was successful in 16 patients (72.7 %). Twenty-four hours after surgery, 17 patients (77.2 %) improved by a minimum of 1 point on NIHSS, 14 patients (63.6 %) improved by three and more points; two patients deteriorated by two and five points, the latter treated initially with systemic thrombolysis due to intracranial hemorrhage. No other intracranial hematoma was observed. During 30 days following surgery, two patients died (9 % mortality rate) due to severity of initial stroke. On discharge, four patients were classified as mRS 0, five patients as mRS 1, five patients as mRS 2 and six patients as mRS 4. Favorable recovery (mRS 0–2) was achieved in 14 patients (63.6 %). No change in mRS was observed at three months.

Conclusions

Our results suggest that emergent surgical desobliteration of occluded eICA can lead to favorable recovery in a majority of patients. Patient selection based on penumbra imaging is crucial. Given the popularity and simplicity of carotid endarterectomy, the procedure should by no means be abandoned in the treatment of acute eICA occlusion.     

Composition and fate of gas and oil released to the water column during the Deepwater Horizon oil spill

Quantitative information regarding the endmember composition of the gas and oil that flowed from the Macondo well during the Deepwater Horizon oil spill is essential for determining the oil flow rate, total oil volume released, and trajectories and fates of hydrocarbon components in the marine environment. Using isobaric gas-tight samplers, we collected discrete samples directly above the Macondo well on June 21, 2010, and analyzed the gas and oil. We found that the fluids flowing from the Macondo well had a gas-to-oil ratio of 1,600 standard cubic feet per petroleum barrel. Based on the measured endmember gas-to-oil ratio and the Federally estimated net liquid oil release of 4.1 million barrels, the total amount of C₁-C₅ hydrocarbons released to the water column was 1.7 × 10¹¹ g. The endmember gas and oil compositions then enabled us to study the fractionation of petroleum hydrocarbons in discrete water samples collected in June 2010 within a southwest trending hydrocarbon-enriched plume of neutrally buoyant water at a water depth of 1,100 m. The most abundant petroleum hydrocarbons larger than C₁-C₅ were benzene, toluene, ethylbenzene, and total xylenes at concentrations up to 78 μg L^-1. Comparison of the endmember gas and oil composition with the composition of water column samples showed that the plume was preferentially enriched with water-soluble components, indicating that aqueous dissolution played a major role in plume formation, whereas the fates of relatively insoluble petroleum components were initially controlled by other processes.     

Evaluating early education programmes

This paper examines a variety of methods for evaluating early education programmes, based on examples from developing as well as developed countries. It considers various components of programme, the size of research studies, and their “outcomes”. It is argued that future policy-makers will require stricter cost-benefit analyses before making funds available for programmes of early childhood education. Because programmes on health, literacy, income generation and skill training are strong competitors for governmental and NGO money, Early Childhood Education will have to prove to policy-makers and donors that it has measurable cost effective outcomes.     

The thermodynamic dissociation constants of four non-steroidal anti-inflammatory drugs by the least-squares nonlinear regression of multiwavelength spectrophotometric pH-titration data

The mixed dissociation constants of four non-steroidal anti-inflammatory drugs (NSAIDs) ibuprofen, diclofenac sodium, flurbiprofen and ketoprofen at various ionic strengths I of range 0.003-0.155, and at temperatures of 25 degrees C and 37 degrees C, were determined with the use of two different multiwavelength and multivariate treatments of spectral data, SPECFIT/32 and SQUAD(84) nonlinear regression analyses and INDICES factor analysis. The factor analysis in the INDICES program predicts the correct number of components, and even the presence of minor ones, when the data quality is high and the instrumental error is known. The thermodynamic dissociation constant pK(a)(T) was estimated by nonlinear regression of (pK(a), I) data at 25 degrees C and 37 degrees C. Goodness-of-fit tests for various regression diagnostics enabled the reliability of the parameter estimates found to be proven. PALLAS, MARVIN, SPARC, ACD/pK(a) and Pharma Algorithms predict pK(a) being based on the structural formulae of drug compounds in agreement with the experimental value. The best agreement seems to be between the ACD/pK(a) program and experimentally found values and with SPARC. PALLAS and MARVIN predicted pK(a,pred) values with larger bias errors in comparison with the experimental value for all four drugs.     

What is a "normal" right ventricle?

AIMS: The aim of this project was to define normal values of right ventricular (RV) volumes and ejection fraction (EF) in healthy population using 2D echocardiography. METHODS AND RESULTS: The "patient" group comprised 91 healthy volunteers aged 17-62 years. RV volumetry was based on ellipsoidal shell model method. Left ventricular (LV) volumes were assessed by Teichholz formula. All volumes were indexed per m(2) of BSA and the rate distribution of measured and calculated values were evaluated. The normal range of individual parameters was expressed as mean value+/-2 standard deviations (delta). A pair test was used to compare corresponding results of the RV and LV measurements. The regression analysis was used to test the relationship between LV and RV volumes and age. Indexed enddiastolic and endsystolic RV volumes were 79.1+/-29.9ml and 32.6+/-19.7ml, respectively, EF being 50+/-9.7% in men and 58+/-13.6% in women. No correlation with patient's age was observed. CONCLUSION: Enddiastolic and endsystolic volumes of RV were significantly higher than those of LV. EF of RV was lower as compare to LV. Right ventricular EF in men was lower than that in women. There was no correlation between EF and patient's age.     

CD30 (Ber-H2) expression by thymocytes and thymic epithelial cells during the late first and second trimester of gestation: an immunohistochemical and in situ hybridization (ISH) study.

BACKGROUND: The exact biological function of CD30 in the thymus during development has been only partially elucidated, although data indicate it may be involved in negative selection. This study was prompted by the observation of a positive reaction of thymic epithelial cells (TECs), Hassall's corpuscles, and thymocytes with the monoclonal antibody CD30 during the late first and second trimester. MATERIAL/METHODS: Twenty paraffin-embedded fetal thymus specimens at the late first and second trimester were investigated by conventional histology and immunohistology for CD30 expression. To provide additional information on the nature and localization of CD30+ thymocytes and CD30+ TECs, in situ hybridization (ISH) was performed on the specimens. Results: 1) In the medulla, a statistically significant difference between CD30+ thymocytes from the late first trimester and those from the second trimester (p<0.0001, t-test) was demonstrated. No significant difference was found concerning CD30+ thymocytes in the cortex. 2) Many medullary TECs and Hassall's corpuscles showed high expression of CD30 during the second trimester, whereas small numbers of CD30+ TECs were found during the late first trimester. No statistically significant difference was found concerning CD30+ TECs in the cortex. CD30 was expressed by ISH in many cells in the medulla and along the septa, whereas the cortex showed little if any expression. Accordingly, a higher CD30 expression was found in medullary than in cortical thymocytes. CONCLUSIONS: Comparison of CD30 expression by TECs and thymocytes during the late first trimester and second trimester suggests an important role for CD30 in thymic selection.     

Selective antidopaminergic effects of S(+)N-n-propylnoraporphines in limbic versus extrapyramidal sites in rat brain: comparisons with typical and atypical antipsychotic agents

Dopamine (DA), injected unilaterally into rat forebrain after pretreatment with a monoamine oxidase inhibitor, equipotently induced locomotor arousal when placed in the nucleus accumbens septi (a limbic site) and contralateral deviation of the head when placed in the corpus striatum (an extrapyramidal target); testing was done with an ED₅₀ dose of DA (16 µg). Systemic injections (IP) of the representative typical neuroleptic haloperidol showed high potency and minorstriatal selectivity against the behavioral effects of intracerebral DA [accumbens ID₅₀=0.090, striatum=0.027 mg/kg (0.24 and 0.072 µmol/kg); ID₅₀ ratio=3.3, favoring striatum]. The atypical antipsychotic agent clozapine was less potent against DA in both brain regions but, paradoxically, showed ever greater striatal selectivity [ID₅₀=12 and 1.4 mg/kg (37 and 4.2 µmol/kg); ratio=8.8, favoring striatum], while its analog, the piperazinyl-dibenzothiazepine ICI-204,636 showed intermediate potency and the lowest striatal selectivity of these three neuroleptic agents [ID₅₀=1.8 and 0.88 mg/kg (4.1 and 2.0 µmol/kg); ratio=2.1]. In striking contrast, the S(+) isomers of N-n-propylnorapomorphine, its orally active 10,11-methylenedioxy prodrug derivative, and its 11-monohydroxy analog all induced potent antagonism oflimbic DA but had little effect on extrapyramidal injections of DA except at high systemic doses [ID₅₀, accumbens=0.18–0.52, striatal=10–15 mg/kg (0.50–1.6 and 29–42 µmol/kg); regional ID₅₀ ratios=18–69, favoring accumbens]. The S(+)aporphines showed limbic potency similar to that of haloperidol and 25–73 times greater than that of clozapine. The S(+)11-OH-aporphine was 2.7–3.1 times more potent (on a molar dose basis) than the other aporphines against DA in accumbens, and 0.5, 8 and 73 times as potent as haloperidol, ICI-204,636 and clozapine. The significantly dissimilar slopes of dose-effect functions for the two groups of agents suggest that different actions may mediate the limbic effects of the aporphines and the neuroleptics tested. ICI-204-636 appears to be pharmacologically similar to clozapine, but 2.1 times more potents versus limbic-DA. The S(+)N-n-propylnoraporphines are potent and regionally highly selectivelimbic DA antagonists and S(+)-11-hydroxy-N-n-propylnoraporphine is orally active. These and other aporphine analogs are proposed for development as potential atypical antipsychotic agents with a low risk of extrapyramidal neurological side effects, and the present methods are proposed for predicting relative limbic versus extrapyramidal antidopaminergic activity.