Safety and efficacy of modified endoscopic ultrasound-guided selective N-butyl-2-cyanoacrylate injections for gastric variceal hemorrhage in left-sided portal hypertension

BACKGROUND Gastric variceal hemorrhage is one of the primary manifestations of left-sided portal hypertension(LSPH).The hemorrhage is fatal and requires safe and effective interventions.AIM To evaluate the clinical safety and efficacy of modified endoscopic ultrasound(EUS)-guided selective N-butyl-2-cyanoacrylate(NBC)injections for gastric variceal hemorrhage in LSPH.METHODS A retrospective observational study of patients with LSPH-induced gastric variceal hemorrhage was conducted.Preoperative EUS evaluations were performed.Enrolled patients were divided into modified and conventional groups according to the NBC injection technique.The final selection of NBC injection technique depended on the patients’preferences and clinical status.The technical and clinical success rates,operation time,NBC doses,perioperative complications,postoperative hospital stay,and recurrent bleeding rates were analyzed,respectively.RESULTS A total of 27 patients were enrolled.No statistically significant differences were observed between the two groups regarding baseline characteristics.In comparison to patients in the conventional group,patients in the modified group demonstrated significantly reduced NBC doses(2.0±0.6 mL vs 3.1±1.0 mL;P=0.004)and increased endoscopic operation time(71.9±11.9 min vs 22.5±6.7 min;P<0.001).Meanwhile,the two groups had no significant difference in the technical and clinical success rates,perioperative complications,postoperative hospital stay,and recurrent bleeding rates.CONCLUSION Modified EUS-guided selective NBC injections demonstrated safety and efficacy for LSPH-induced gastric variceal hemorrhage,with advantages of reduced injection dose and no radiation risk.Drawbacks were time consumption and technical challenge.

Long-term result of endoscopic Histoacryl （N-butyl-2-cyanoacrylate）injection for treatment of gastric varices

AIM:To evaluate the long-term efficacy and safety of endoscopic obliteration with Histoacryl for treatment of gastric variceal bleeding and prophylaxis.METHODS:Between January 1994 and March 2010 at SoonChunHyang University Hospital,a total of 127 patients with gastric varices received Histoacryl injections endoscopically.One hundred patients underwent endoscopic Histoacryl injections because of variceal bleeding,the other 27 patients received such injections as a prophylactic procedure.RESULTS:According to Sarin classification,56 patients were GOV1,61 patients were GOV2 and 10 patients were IGV.Most of the varices were large(F2 or F3,111 patients).The average volume of Histoacryl per each session was 1.7±1.3 cc and mean number of sessions was 1.3±0.6.(1 session-98 patients,2 sessions-25 patients,≥3 sessions-4 patients).Twenty-seven patients with high risk of bleeding(large or fundal or RCS+or Child C) received Histoacryl injection as a primary prophylactic procedure.In these patients,hepatitis B virus was the major etiology of cirrhosis,25 patients showed GOV1 or 2(92.6%)and F2 or F3 accounted for 88.9%(n=24).The rate of initial hemostasis was 98.4%and recurrent bleeding within one year occurred in 18.1%of patients.Successful hemostasis during episodes of rebleeding was achieved in 73.9%of cases.Median survival was 50 mo (95%CI 30.5-69.5).Major complications occurred in 4 patients(3.1%).The rebleeding rate in patients with hepatocellular carcinoma or GOV2 was higher than in those with other conditions.None of the 27 subjects who were treated prophylactically experienced treatment-related complications.Cumulative survival rates of the 127 patients at 6 mo,1,3,and 5 years were 92.1%,84.2%,64.2%,and 45.3%,respectively.The 6 mo cumulative survival rate of the 27 patients treated prophylactically was 75%.CONCLUSION:Histoacryl injection therapy is an effective treatment for gastric varices and also an effective prophylactic treatment of gastric varices which carry high risk of bleeding.

Study of glue extrusion after endoscopic N-butyl-2-cyanoacrylate injection on gastric variceal bleeding

AIM:To investigate glue extrusion after endoscopic N-butyl-2-cyanoacrylate injection on gastric variceal bleeding and to evaluate the long-term efficacy and safety of this therapy.METHODS:A total of 148 cirrhotic patients in our hospital with esophagogastric variceal bleeding(EGVB) were included in this study.N-butyl-2-cyanoacrylate was mixed with lipiodol in a 1:1 ratio and injected as a bolus of 1-3 mL according to variceal size.Patients underwent endoscopic follow-up the next week,fourth week,second month,fourth month,and seventh month after injection and then every 6 mo to determine the cast shape.An abdominal X-ray fi lm and ultrasound or computed tomographic scan were also carried out in order to evaluate the time of variceal disappearance and complete extrusion of the cast.The average follow-up time was 13.1 mo.RESULTS:The instantaneous hemostatic rate was 96.2%.Early re-bleeding after injection in 9 cases(6.2%) was estimated from rejection of adhesive.Late re-bleeding occurred in 12 patients(8.1%) at 2-18 mo.The glue cast was extruded into the lumen within one month in 86.1% of patients and eliminated within one year.Light erosion was seen at the injection position and mucosa edema in the second week.The glue casts were extruded in 18 patients(12.1%) after one week and in 64 patients(42.8%) after two weeks.All kinds of glue clumping shapes and colors on endoscopic examination were observed in 127 patients(86.1%) within one month,including punctiform,globular,pillar and variform.Forty one patients(27.9%) had glue extrusion after 3 mo and 28 patients(28.9%) after six months.The extrusion time was not related to the injection volume of histoacryl.Obliteration was seen in 70.2%(104 cases) endoscopically.The main complication was re-bleeding resulting from extrusion.The prognosis of the patients depended on the severity of the underlying liver disease.CONCLUSION:Endoscopic injection of cyanoacrylate is highly effective for gastric varices bleeding.The glue clump shape is correlated with anatomic structure of vessels.The time of extrusion was not related to dosage of the glue.

N-butyl-2-cyanoacrylate, iso-amyl-2-cyanoacrylate and hypertonic glucose with 72% chromated glycerin in gastric varices

cyanoacrylate and a mixture of 72% chromated glycerinwith hypertonic glucose solution in management ofgastric varices.METHODS： Ninety patients with gastric varicespresented to Endoscopy Unit of Ain Shams UniversityHospital were included. They were randomly allocatedinto three groups; each group included 30 patients treatedwith intravariceal sclerosant injections in biweeklysessions till complete obturation of gastric varices;Group I （n-butyl-2-cyanoacrylate; Histoacryl？）, GroupII （iso-amyl-2-cyanoacrylate; Amcrylate？） and GroupIII （mixture of 72% chromated glycerin; Scleremo？with glucose solution 25%）. All the procedures wereperformed electively without active bleeding. Recruitedpatients were followed up for 3 mo.RESULTS： 26% of Scleremo group had bleeding duringpuncture vs 3.3% in each of the other two groups withsignificant difference, （P 〈 0.05）. None of Scleremogroup had needle obstruction vs 13.3% in each of theother two groups with no significant difference, （P 〉0.05）. Rebleeding occurred in 13.3% of Histoacryl andAmcrylate groups vs 0% in Scleremo group with nosignificant difference. The in hospital mortality was 6.6%in both Histoacryl and Amcrylate groups, while it was0% in Scleremo group with no significant difference. Inthe first and second sessions, the amount of Scleremoneeded for obturation was significantly high, while the amount of Histoacryl was significantly low. Scleremo was the less costly of the two treatments. CONCLUSION： All used sclerosant substances showed efficacy and success in management of gastric varices with no significant differences except in total amount,cost and bleeding during puncture.

Cerebral and splenic infarctions after injection of N-butyl-2-cyanoacrylate in esophageal variceal bleeding

Variceal bleeding is the most serious complication of portal hypertension,and it accounts for approximately one fifth to one third of all deaths in liver cirrhosis patients.Currently,endoscopic treatment remains the predominant method for the prevention and treatment of variceal bleeding.Endoscopic treatments include band ligation and injection sclerotherapy.Injection sclerotherapy with N-butyl-2-cyanoacrylate has been successfully used to treat variceal bleeding.Although injection sclerotherapy with N-butyl-2-cyanoacrylate provides effective treatment for variceal bleeding,injection of N-butyl-2-cyanoacrylate is associated with a variety of complications,including systemic embolization.Herein,we report a case of cerebral and splenic infarctions after the injection of N-butyl-2-cyanoacrylate to treat esophageal variceal bleeding.

Modified endoscopic ultrasound-guided selective N-butyl-2-cyanoacrylate injections for gastric variceal hemorrhage in left-sided portal hypertension:A case report

BACKGROUND Left-sided portal hypertension(LSPH),also known as sinistral portal hypertension or regional portal hypertension,refers to extrahepatic portal hypertension caused by splenic vein obstruction or stenosis.N-butyl-2-cyanoacrylate(NBC)has been widely used in the endoscopic hemostasis of portal hypertension,but adverse events including renal or pulmonary thromboembolism,mucosal necrosis and gastrointestinal(GI)bleeding may occur after treatment.Herein,we report successfully managing gastric variceal(GV)hemorrhage secondary to LSPH using modified endoscopic ultrasound(EUS)-guided selective NBC injections.CASE SUMMARY A 35-year-old man was referred to our hospital due to an upper GI hemorrhage.Gastroscopy revealed GV hemorrhage and computed tomography venography(CTV)confirmed LSPH.The patient requested endoscopic procedures and rejected surgical therapies including splenectomy.EUS-guided selective NBC injections were performed and confluences of gastric varices were selected as the injection sites to reduce the injection dose.The“sandwich”method using undiluted NBC and hypertonic glucose was applied.No complications occurred.The patient was followed up regularly after discharge.Three months later,the follow-up gastroscopy revealed firm gastric submucosa with no sign of NBC expulsion and the follow-up CTV showed improvements in LSPH.No recurrent GI hemorrhage was reported during this follow-up period.CONCLUSION EUS-guided selective NBC injection may represent an effective and economical treatment for GV hemorrhage in patients with LSPH.

Endovascular treatment of traumatic direct carotid cavernous fistulas with n-Butyl-2-Cyanoacrylate

Objective To explore the method and safety of endovascular treatment of traumatic direct carotid cavernous fistulas with n-Butyl-2-Cyanoacrylate. Method A total of 11 patients with traumatic direct carotid cavernous fistulas treated by endovascular embolization with n-Butyl-2-Cyanoacrylate. (n-BCA) were retrospectively analyzed,including the

Efficient one-pot synthesis of n-butyl levulinate from carbohydrates catalyzed by Fe_2(SO_4)_3

Butyl levulinate（BL） is a promising new candidate as diesel fuel and fuel additive. In this study, an efficient process for a one-pot synthesis of BL from biomass-derived carbohydrates in butanol medium with the catalysis of metal sulfates was developed. The catalytic activity of a series of metal sulfates for the synthesis of BL from fructose was investigated. Among various metal sulfates, ferric sulfate Fe（SO）was found to be the most efficient catalyst, which gave a remarkably high BL yield of 62.8 mol% under the conditions of 463 K, 3 h, a catalyst dosage of 5.0 g/L, and fructose concentration of 25 g/L. Different carbohydrates including glucose, cellulose, inulin and sucrose were also used for one-pot synthesis of BL with the catalysis of Fe（SO）, showing the yields of 39.6, 30.5, 56.6 and 50.1 mol%, respectively. In addition,the recycling and reuse of Fe（SO）was studied by characterizing them using powder X-ray diffraction（XRD）, scanning electron microscope（SEM）, X-ray photoelectron spectroscopy（XPS）. A plausible reaction pathway for the one-pot synthesis of BL from fructose was proposed. This study provides a facile and feasible way for the synthesis of BL from biomass.

Prevalence of gastric varices and results of sclerotherapy with N-butyl 2 cyanoacrylate for controlling acute gastric variceal bleeding

AIM： To study the prevalence, predictors and control of bleeding following N-butyl 2 cyanoacrylate （NBC） sclerotherapy of gastric varix （GV）. METHODS： We analyzed case records of 1436 patients with portal hypertension, who underwent endoscopy during the past five years for variceal screening or upper gastrointestinal （GI） bleeding. Fifty patients with bleeding GV underwent sclerotherapy with a mean of 2 mL NBC for control of bleeding. Outcome parameters were primary hemostasis （bleeding control within the first 48 h）, recurrent bleeding （after 48 h of esophagogastro-duodenoscopy） and in-hospital mortality were analyzed. RESULTS： The prevalence of GV in patients with portal hypertension was 15% （220/1436） and the incidence of bleeding was 22.7% （50/220）. Out of the 50 bleeding GV patients, isolated gastric varices （IGV-Ⅰ） were seen in 22 （44%）, gastro-oesophageal varices （GOV） on lesser curvature （GOV-Ⅰ） in 16 （32%）, and GOV on greater curvature （GOV-Ⅱ） in 15 （30%）. IGV-Ⅰ was seen in 44% （22/50） patients who had bleeding as compared to 23% （39/170） who did not have bleeding （P 〈 0.003）. Primary hernostasis was achieved with NBC in all patients. Re-bleeding occurred in 7 （14%） patients after 48 h of initial sclerotherapy. Secondary hemostasis was achieved with repeat NBC sclerotherapy in 4/7 （57%）. Three patients died after repeat sclerotherapy, one during transjugular intrahepatic portosystemic stem shunt （TIPSS）, one during surgery and one due to uncontrolled bleeding. Treatment failure-related mortality rate was 6% （3/50）. CONCLUSION： GV can be seen in 15% of patients with portal hypertension and the incidence of bleeding is 22.7%. NBC is highly effective in controlling GV bleeding. In hospital mortality of patients with bleeding GV is 6%.

Preparation,Characterization of Dawson-type Heteropoly Acid Cerium（Ⅲ） Salt and Its Catalytic Performance on the Synthesis of n-Butyl Acetate

A novel cerium(Ⅲ) salt of Dawson type tungstophosphoric acid(Ce2P2W18O62·16H2O) was prepared by doping cerous nitrate in H6P2W18O62·13H2O powder and characterized by thermogravimetry and differential thermal analyses(TG/DTA),Fourier transform infrared spectroscopy(FT-IR),X-ray powder diffraction(XRD),pyridine infrared spectroscopy(Py-IR) and scanning electron microscopy(SEM).Its catalytic activity was evaluated by the probe reaction of synthesis of n-butyl acetate with acetic acid and n-butanol.The effects of various parameters such as molar ratio of n-butanol to acetic acid,reaction temperature,reaction time,and catalyst amount have been studied by single factor experiment.The results show that Ce2P2W18O62·16H2O behaved as an excellent heterogeneous catalyst in the synthesis of n-butyl acetate.The optimum synthetic conditions were determined as follows︰molar ratio of n-butanol to acetic acid at 2.0︰1.0,mass of the catalyst being 1.44% of the total reaction mixture,reaction temperature of 120 ℃ and reaction time of 150 min.Under above conditions,the conversion of acetic acid was above 97.8%.The selectivity of n-butyl acetate based on acetic acid was,in all cases,nearly 100%.The catalysts could be recycled and still exhibited high catalytic activity with 90.4% conversion after five cycles of reaction.It was found by means of TG-DTA and Py-IR that the catalyst deactivation was due to the adsorption of a complex of by-product on the active sites on catalysts surface or the catalyst loss in its separation from the products.Compared with using sulfuric acid as catalyst,the present procedure with Ce2P2W18O62·16H2O is a green productive technology due to simple process,higher yield,catalyst recycling and no corrosion for the production facilities.

Esterification of levulinic acid to n-butyl levulinate over heteropolyacid supported on acid-treated clay

Levulinic acid has been identified as a promising green, biomass-derived platform chemical. n-Butyl levulinate is used as an important intermediate having diverse applications. The present work focuses on the synthesis of n-butyl levulinate by esterification of levulinic acid with n-butanol using heteropolyacid （HPA） supported on acid-treated clay montmorillonite （K10）. 20% （w/w） dodecatungestophosphoric acid （DTPA） supported on K10 was found to be the most efficient catalyst with 97% levulinic acid conversion and 100% selectivity towards n-butyl levulinate. Effects of various process parameters were studied to examine the efficacy of 20% （w/w） DTPA/K10 for optimization of the activity.

n-Butyl Pyridinium Nitrate as a Reusable Ionic Liquid Medium for Knoevenagel Condensation

The Knoevenagel condensation of carbonyl substrates with active methylene compounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in moderate yields.

Reactive Distillation for Producing n-Butyl Acetate:Experiment and Simulation

In this paper, a reactive distillation (RD) column was applied for synthesis n-butyl acetate from n-butanol and acetic acid. The Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetic model and an equilibrium stage model for separation were employed to study the RD process. The results obtained from the equilibrium stage model agreed well with the experiments. The effects of operating variables on the n-butanol conversion and n-butyl acetate purity were further investigated. The optimal column configuration for the production of n-butyl acetate was designed with 5 rectifying stages, 8 reaction stages and 13 stripping stages by the simulation study. According to the simulation results, n-butanol conversion and n-butyl acetate purity all reached greater than 96%.

Di-(n-butyl)-phthalate-induced Oxidative Stress and Depression-like Behavior in Mice with or without Ovalbumin Immunization

Objective To investigate the relationship between atopic allergy and depression and the role of DBP in the development of depression. Methods BALB/c mice were randomly divided into eight groups：saline;ovalbumin （OVA）-immunized;saline＋DBP （0.45 mg/kg·183;d）; saline＋DBP （45 mg/kg·d）; DBP （0.45 mg/kg·d） OVA-immunized; DBP （45 mg/kg·d） OVA-immunized; saline＋hydrocortisone （30 mg/kg·d）; and hydrocortisone （30 mg/kg·d）-exposed OVA-immunized. Behavior （e.g. open-field, tail suspension, and forced swimming tests）, viscera coefficients （brain and spleen）, oxidative damage [e.g. reactive oxygen species （ROS）, malondialdehyde （MDA）, and glutathione （GSH）], as well as levels of IgE and IL-4, were then analyzed. Results In the saline and OVA groups, the degree of depression symptoms in mice increased with increasing DBP concentration. Additionally, the OVA-immunity groups were associated with more serious depressive behavior compared with the same exposure concentration in the saline group. Oxidative damage was associated with a dose-dependent increase in DBP in the different groups. IL-4 and IgE levels were associated with low-dose DBP stimulation, which changed to high-dose inhibition with increasing DBP exposure, possibly due to spleen injury seen at high DBP concentrations.Conclusion Development of an atopic allergy has the potential to increase the risk of depression in mice, and it seems that DBP helps OVA to exert its effect in our present model. Moreover, the results of our study implicate a certain connection between brain oxidative stress and depression, which deserves a further exploration.

Reactive dividing-wall column for the co-production of ethyl acetate and n-butyl acetate

Reactive dividing-wall column(RDWC) technology plays a critical role in the energy saving and high efficiency of chemical process.In this article, the process of co-producing ethyl acetate(EA) and n-butyl acetate(BA) with RDWC was studied.BA was not only the product, but also acted as entrainer to remove the water generated by the two esterification reactions.Experiments and simulations of the co-production process were carried out.It was found that the experimental results were in good agreement with the simulation results.Two kinds of RDWC structures(RDWC-FC and RDWC-RS) were proposed, and the co-production process operating parameters of the two types of RDWC were optimized by Aspen Plus respectively.The optimal operating parameters of the RDWC-FC were determined as follows: 0.6 of the reflux ratio of aqueous phase(RR), 0.66 of the vapor split(R_V) and 0.51 of the liquid split(R_L).And the optimal operating parameters of the RDWC-RS were shown as follows: RR was 0.295 and R_V was 0.61.Furthermore, the energy saving analysis of the co-production process was based on the annual output of 10000 tons of EA, compared with the traditional reaction distillation(RD) to prepare EA and BA, the reboiler duty of the RDWC-FC column could save 20.4%, TAC saving 23.6%; RDWC-RS reboiler energy consumption could save 17.0%, TAC 22.2%.

Vapor-Liquid Equilibria for Dimethyl Carbonate-n-Butyl Acetate Binary System at 101.325kPa

The vapor-liquid equilibrium (VLE) data for the dimethyl carbonate-n-butyl acetate binary system were measured by an Ellis equilibrated distillator. The experimental data were checked for their thermodynamic consistency through statistical methods. The VLE data was correlated with Wilson and NRTL activity coefficient models and also with the calculation of the vapor phase fugacity coefficient by the modified Peng-Robinson equation of state.

Endoscopic management of Dieulafoy's lesion using Isoamyl-2-cyanoacrylate

Dieulafoy's lesion (DL) is a rare but important cause of obscure gastrointestinal bleeding that may be over-looked during diagnostic endoscopy. Mortality rates are similar to those of other causes for gastrointestinal bleeding. Diagnosis by upper endoscopy is the modal-ity of choice during acute bleeding. In the absence of active bleeding, the lesion resembles a raised nipple or visible vessel. There are no guidelines regarding effective selective therapy for DL, when diagnosed, en-doscopist experience is the major determinant of the treatment strategy. Following our strategy, an expert endoscopist with a skilled assistant should have a high rate of successful DL diagnosis when an obscured gas-trointestinal lesion is suspected. Cyanoacryltes com-pounds have been used successfully in management of Gastric varices and DLs. To our knowledge, there have been no previous reports regarding use of isoamyl-2-cyanoacrylate (AMCRYLATE ; Concord Drugs Ltd.,Hyderabad, India) as an effective therapy for gastric DL without serious complications. In our case study, Isoamyl-2-cyanoacrylate (AMCRYLATE) was effective and safe for treating DL. Surgical wedge resection of the lesion should be considered as a therapeutic option if endoscopic therapy fails.

Degradation of n-butyl xanthate using fly ash as heterogeneous Fenton-like catalyst

Heterogeneous Fenton-like process using fly ash as a catalyst was studied to degrade n-butyl xanthate form aqueous solution. The different reaction parameters on the degradation efficiency of the process were investigated. The fly ash/H2O2 catalyst possesses a high oxidation activity for n-butyl xanthate degradation in aqueous solution. It is found that both the dosage of catalyst and initial solution pH significantly affect the n-butyl xanthate conversion efficient. The results indicate that by using 1.176 mmol/L H2O2 and 1.0 g/L fly ash catalyst with mass fraction of 4.14% Fe(III) oxide at pH 3.0, almost 96.90% n-butyl xanthate conversion and over 96.66% COD removal can be achieved within 120 min with heterogeneous catalysis by fly ash. CS2 as an intermediate of n-butyl xanthate oxidation. Finally, it is demonstrated that the fly ash/H2O2 catalytic oxidation process can be an efficient method for the treatment of n-butyl xanthate containing wastewater.

Vapor Pressure, Vaporization Enthalpy, Standard Enthalpy of Formation and Standard Entropy of n-Butyl Carbamate

The vapor pressures of n-butyl carbamate were measured in the temperature range from 372.37 K to 479.27 K and fitted with Antoine equation. The compressibility factor of the vapor was calculated with the Virial equation and the second virial coefficient was determined by the Vetere model. Then the standard enthalpy of vaporization for n-butyl carbamate was estimated. The heat capacity was measured for the solid state(299.39–324.2 K) and liquid state(336.65–453.21 K) by means of adiabatic calorimeter. The standard enthalpy of formation ΔfH[crystal(cr),298.15 K] and standard entropy S(crystal,298.15 K) of the substance were calculated on the basis of the gas-phase standard enthalpy of formation ΔfH(g,298.15 K)and gas-phase standard entropy S(g,298.15 K), which were estimated by the Benson method. The results are acceptable, validated by a thermochemical cycle.

Reactivity Ratios for Microemulsion Copolymeriration of N-butyl Maleimide and Styrene

The oil-in-water microemulsion containing N-butyl maleimide(NBMI. M_1) and styrene(St, M_2) was prepared. The complexation properties of NBMI and St in microemulsion were investigated by means of 1H-NMR. With the participation of charge-transfer complex(CTC). four reactivity ratios and the relative reactivity of free monomers and CTC were obtained. The result was compared with that measured by Mayo-Lewis method.