Background Endovascular treatment of intracranial aneurysms usually involves stent-assisted coiling(SAC)and flow diverters.Glycoprotein IIb/IIIa inhibitors such as tirofiban and dual antiplatelet therapy(DAPT)are requ...Background Endovascular treatment of intracranial aneurysms usually involves stent-assisted coiling(SAC)and flow diverters.Glycoprotein IIb/IIIa inhibitors such as tirofiban and dual antiplatelet therapy(DAPT)are required to prevent thromboembolic complications afterwards.We sought to determine the safety of tirofiban and DAPT in these cases.Methods We conducted a retrospective analysis of our database for patients with intracranial aneurysms who underwent SAC or flow diversion.The tirofiban-DAPT protocol used is described.Data regarding duration of infusion,placement of external ventricular devices(EVDs),complications,haemoglobin levels and platelet count before and 24 hours after antiplatelet therapy were collected and analysed.results One-hundred and forty-one patients with 148 aneurysms/procedures were included.110 aneurysms were treated acutely and 38 electively.Minor and major haemorrhagic events were recognised in 20%(30/148)aneurysms.Only 5(3.4%)intracerebral haemorrhages were symptomatic:3 cortical/SAH and 2 EVD-related.The average blood volume in symptomatic haemorrhages was 24.8 cc versus 5.42 cc in asymptomatic haemorrhages(p=0.002).The rate of EVD-related haemorrhages was 15.7%(19/121)and only 2(1.7%)were symptomatic.Most haemorrhagic events occurred in ruptured aneurysms(90.1%,p=0.01).No significant change in platelet count or haemoglobin levels before and 24 hours after administration of tirofiban and DAPT was documented.Concomitant administration of heparin did not increase haemorrhagic events.Conclusion The use of the GP IIb/IIIa inhibitors tirofiban and DAPT in this series was safe.Tirofiban and DAPT did not affect platelet count or haemoglobin levels and did not increase rate of symptomatic haemorrhages or thromboembolic complications.展开更多
background While diffuse atherosclerotic disease affecting the posterior circulation has been described extensively,the prevalence,natural history and angiographic characteristics of isolated symptomatic basilar arter...background While diffuse atherosclerotic disease affecting the posterior circulation has been described extensively,the prevalence,natural history and angiographic characteristics of isolated symptomatic basilar artery stenosis(ISBAS)remain unknown.Methods We reviewed our prospective institutional database to identify patients with≥50% symptomatic basilar artery(BA)stenosis without significant atherosclerotic burden in the vertebral or posterior cerebral arteries.Stroke mechanism,collateral circulation,and degree and length of stenosis were analysed.The primary outcome was time from index event to new transient ischaemic attack(TIA),acute ischaemic stroke(AIS)or death.Other outcome variables included modified Rankin Scale(mRS)score on discharge and last follow-up.results Of 6369 patients with AIS/TIA,91(1.43%)had ISBAS.Seventy-three(80.2%)patients presented with AIS and 18(19.8%)with TIA.Twenty-nine(31.9%)were women and the median age was 66.8±13.6 years.The mean follow-up time was 2.7 years.The most common stroke mechanism was artery-to artery thromboembolism(45.2%),followed by perforator occlusion(28.7%)and flow-dependent/hypoperfusion(15.1%).The percentage of stenosis was lower in patients who had favourable outcome compared with those with mRS 3-6 on discharge(78.3±14.3 vs 86.9±14.5,p=0.007).Kaplan-Meier curves showed higher recurrence/death rates in patients with≥80% stenosis,mid-basilar location and poor collateral circulation.Approximately 13% of patients with ISBAS presented with complete BA occlusion.Conclusion ISBAS is an uncommon(1.43%)cause of TIA and AIS.Men in their 60s are mostly affected,and artery-to artery embolism is the most common stroke mechanism.Mid-basilar location,≥80% stenosis and poor collateral circulation are important factors associated with worse prognosis.展开更多
Oil production and mainte nance are essential issues in naturally fractured reservoirs because they are the largest and most productive on earth.However,they present early water and gas channeling but could be remedia...Oil production and mainte nance are essential issues in naturally fractured reservoirs because they are the largest and most productive on earth.However,they present early water and gas channeling but could be remediated by using foaming agents to control these phenomena through blocking channeling areas.In Mexico these reservoirs have pressure up to 5,500 psi,high temperature up to 200℃,salinity up to400,000 ppm,and hardness up to 250,000 ppm;due to these thermodynamic conditions,there has been no available technology to form stable enough foams.In this work,a foaming supramolecular surfactant with the capability to chelate Ca^(2+)ions is examined.As a result,surfactant monomers are bridged by captured Ca^(2+)cations leading to the formation of high-molecular-weight oligomers,which significantly increment the viscosity of the solution improving the foam stability,and since at this manner the Ca2+cations are no longer available to precipitate as components of solid salts,the foaming supramolecular surfactant also performs as antiscalant.These observations are explained through quantum theoretical modeling.The foam is stable,effectively blocking the gas channels,whereas in presence of oil the foam is broken leading the oil to pass into the wellbore.The characteristic rheological properties of the foam allow its injection into the formation at a range of flow rates,foam qualities,and shear stress to achieve the flooding and the blocking of a variety of fractured carbonate formations,and the change of the wettability of the matrix,which is a desirable behavior in a huff and puff process,as reported in a previous publication about a successful pilot test of this foam.展开更多
The aim of this work was to investigate whether acamprosate modifies the expression of the enzyme responsible for neuronal NO synthesis (nNOS) in the nucleus accumbens (NAc) of mice chronically treated with morphine a...The aim of this work was to investigate whether acamprosate modifies the expression of the enzyme responsible for neuronal NO synthesis (nNOS) in the nucleus accumbens (NAc) of mice chronically treated with morphine and during the abstinence syndrome induced by naloxone. The enzyme was monitored by the NADPH diaphorase method. The number of cells stained for NADPH diaphorase in the NAc of mice was counted in 40 μm thick coronal brain slices at 40X. The intensity of the histochemical reaction of stained cells from naive morphine plus saline and morphine plus acamprosate treated mice was analyzed by Image Pro Plus 4.5.1. Morphine administered in a slow release preparation increased the stain intensity of the positive neurons. The increase in the NADPH staining persisted after naloxone was given to mice chronically treated with morphine. Acamprosate antagonized the effects induced by chronic morphine treatment in the NAc of mice. These results indicate that up-regulation of nNOS in the NAc is a consequence of the sustained effects of morphine stimulation, which, in turn, may result from an increased in glutamate release during the abstinence syndrome.展开更多
基金This study was supported by an educational grant from Medicure.
文摘Background Endovascular treatment of intracranial aneurysms usually involves stent-assisted coiling(SAC)and flow diverters.Glycoprotein IIb/IIIa inhibitors such as tirofiban and dual antiplatelet therapy(DAPT)are required to prevent thromboembolic complications afterwards.We sought to determine the safety of tirofiban and DAPT in these cases.Methods We conducted a retrospective analysis of our database for patients with intracranial aneurysms who underwent SAC or flow diversion.The tirofiban-DAPT protocol used is described.Data regarding duration of infusion,placement of external ventricular devices(EVDs),complications,haemoglobin levels and platelet count before and 24 hours after antiplatelet therapy were collected and analysed.results One-hundred and forty-one patients with 148 aneurysms/procedures were included.110 aneurysms were treated acutely and 38 electively.Minor and major haemorrhagic events were recognised in 20%(30/148)aneurysms.Only 5(3.4%)intracerebral haemorrhages were symptomatic:3 cortical/SAH and 2 EVD-related.The average blood volume in symptomatic haemorrhages was 24.8 cc versus 5.42 cc in asymptomatic haemorrhages(p=0.002).The rate of EVD-related haemorrhages was 15.7%(19/121)and only 2(1.7%)were symptomatic.Most haemorrhagic events occurred in ruptured aneurysms(90.1%,p=0.01).No significant change in platelet count or haemoglobin levels before and 24 hours after administration of tirofiban and DAPT was documented.Concomitant administration of heparin did not increase haemorrhagic events.Conclusion The use of the GP IIb/IIIa inhibitors tirofiban and DAPT in this series was safe.Tirofiban and DAPT did not affect platelet count or haemoglobin levels and did not increase rate of symptomatic haemorrhages or thromboembolic complications.
文摘background While diffuse atherosclerotic disease affecting the posterior circulation has been described extensively,the prevalence,natural history and angiographic characteristics of isolated symptomatic basilar artery stenosis(ISBAS)remain unknown.Methods We reviewed our prospective institutional database to identify patients with≥50% symptomatic basilar artery(BA)stenosis without significant atherosclerotic burden in the vertebral or posterior cerebral arteries.Stroke mechanism,collateral circulation,and degree and length of stenosis were analysed.The primary outcome was time from index event to new transient ischaemic attack(TIA),acute ischaemic stroke(AIS)or death.Other outcome variables included modified Rankin Scale(mRS)score on discharge and last follow-up.results Of 6369 patients with AIS/TIA,91(1.43%)had ISBAS.Seventy-three(80.2%)patients presented with AIS and 18(19.8%)with TIA.Twenty-nine(31.9%)were women and the median age was 66.8±13.6 years.The mean follow-up time was 2.7 years.The most common stroke mechanism was artery-to artery thromboembolism(45.2%),followed by perforator occlusion(28.7%)and flow-dependent/hypoperfusion(15.1%).The percentage of stenosis was lower in patients who had favourable outcome compared with those with mRS 3-6 on discharge(78.3±14.3 vs 86.9±14.5,p=0.007).Kaplan-Meier curves showed higher recurrence/death rates in patients with≥80% stenosis,mid-basilar location and poor collateral circulation.Approximately 13% of patients with ISBAS presented with complete BA occlusion.Conclusion ISBAS is an uncommon(1.43%)cause of TIA and AIS.Men in their 60s are mostly affected,and artery-to artery embolism is the most common stroke mechanism.Mid-basilar location,≥80% stenosis and poor collateral circulation are important factors associated with worse prognosis.
基金supports granted by Instituto Mexicano del Petr oleo (IMP) through the Project Y.00123 “Procesos de RM en yacimientos carbonatados fracturados de alta salinidad y temperatura con base en el dise~no, desarrollo y escalamiento de productos químicos ad hoc”financially supported by the SENER-CONACYT/Hidrocarburos fund through the Project 146735, D.61029 “Dise~no y síntesis de nuevos prototipos de productos químicos multifuncionales con propiedades dispersantes de asfaltenos modificadoras de la mojabilidad y desemulsificantes”
文摘Oil production and mainte nance are essential issues in naturally fractured reservoirs because they are the largest and most productive on earth.However,they present early water and gas channeling but could be remediated by using foaming agents to control these phenomena through blocking channeling areas.In Mexico these reservoirs have pressure up to 5,500 psi,high temperature up to 200℃,salinity up to400,000 ppm,and hardness up to 250,000 ppm;due to these thermodynamic conditions,there has been no available technology to form stable enough foams.In this work,a foaming supramolecular surfactant with the capability to chelate Ca^(2+)ions is examined.As a result,surfactant monomers are bridged by captured Ca^(2+)cations leading to the formation of high-molecular-weight oligomers,which significantly increment the viscosity of the solution improving the foam stability,and since at this manner the Ca2+cations are no longer available to precipitate as components of solid salts,the foaming supramolecular surfactant also performs as antiscalant.These observations are explained through quantum theoretical modeling.The foam is stable,effectively blocking the gas channels,whereas in presence of oil the foam is broken leading the oil to pass into the wellbore.The characteristic rheological properties of the foam allow its injection into the formation at a range of flow rates,foam qualities,and shear stress to achieve the flooding and the blocking of a variety of fractured carbonate formations,and the change of the wettability of the matrix,which is a desirable behavior in a huff and puff process,as reported in a previous publication about a successful pilot test of this foam.
文摘The aim of this work was to investigate whether acamprosate modifies the expression of the enzyme responsible for neuronal NO synthesis (nNOS) in the nucleus accumbens (NAc) of mice chronically treated with morphine and during the abstinence syndrome induced by naloxone. The enzyme was monitored by the NADPH diaphorase method. The number of cells stained for NADPH diaphorase in the NAc of mice was counted in 40 μm thick coronal brain slices at 40X. The intensity of the histochemical reaction of stained cells from naive morphine plus saline and morphine plus acamprosate treated mice was analyzed by Image Pro Plus 4.5.1. Morphine administered in a slow release preparation increased the stain intensity of the positive neurons. The increase in the NADPH staining persisted after naloxone was given to mice chronically treated with morphine. Acamprosate antagonized the effects induced by chronic morphine treatment in the NAc of mice. These results indicate that up-regulation of nNOS in the NAc is a consequence of the sustained effects of morphine stimulation, which, in turn, may result from an increased in glutamate release during the abstinence syndrome.
