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Sample records for post-esophageal variceal ligation

  1. Sucralfate and Lidocain: Antacid 50:50 solution in Post Esophageal Variceal Band Ligation Pain

    PubMed Central

    Hafeez, Muhammad; Kadir, Ehsan; Aijaz, Anjum

    2016-01-01

    Objective: To compare the effectiveness of pain relief of Sucralfate and lidocain antacid 50:50 solution in post esophageal variceal band ligation pain. Methods: All patients who had under gone Esophageal Variceal Band Ligation (EVBL) were included in the study. Patients un-willing to be included in the study or those who didn’t have post EVBL pain were excluded. Patients with post EVBL pains were divided into two groups: one group was given sucralfate and other was given lidocaine: antacid 50:50 solution. Both were inquired about the duration of the pain relief after the medication. The results were analyzed on SPSS 23. Independent samples T-test was performed to find out whether the difference in duration of pain relief was significantly different in the two groups Results: Out of 110 patients who have EVBL, 66(60.00%) had pain and 44(40.00%) were pain free. In the pain group 46 (69.7%) were given sucralfate and 20 (30.3%) were given lidocain: antacid 50:50 solution. Mean duration of pain relief in two groups was 2.78 (SD ± 2.096) and 2.5 days (SD ±. 0.76) respectively. Independent samples T-test results revealed that there was no statistically significant difference in the duration of pain relief between these two groups with p value 0.426. Conclusion: Both Sucralfate and Lidocain: antacid 50:50 solutions are effective in relieving the post EVBL pain. However, no statistically significant difference in duration of pain relief was detected in separate groups of patients treated with either treatment.

  2. Sucralfate and Lidocain: Antacid 50:50 solution in Post Esophageal Variceal Band Ligation Pain

    PubMed Central

    Hafeez, Muhammad; Kadir, Ehsan; Aijaz, Anjum

    2016-01-01

    Objective: To compare the effectiveness of pain relief of Sucralfate and lidocain antacid 50:50 solution in post esophageal variceal band ligation pain. Methods: All patients who had under gone Esophageal Variceal Band Ligation (EVBL) were included in the study. Patients un-willing to be included in the study or those who didn’t have post EVBL pain were excluded. Patients with post EVBL pains were divided into two groups: one group was given sucralfate and other was given lidocaine: antacid 50:50 solution. Both were inquired about the duration of the pain relief after the medication. The results were analyzed on SPSS 23. Independent samples T-test was performed to find out whether the difference in duration of pain relief was significantly different in the two groups Results: Out of 110 patients who have EVBL, 66(60.00%) had pain and 44(40.00%) were pain free. In the pain group 46 (69.7%) were given sucralfate and 20 (30.3%) were given lidocain: antacid 50:50 solution. Mean duration of pain relief in two groups was 2.78 (SD ± 2.096) and 2.5 days (SD ±. 0.76) respectively. Independent samples T-test results revealed that there was no statistically significant difference in the duration of pain relief between these two groups with p value 0.426. Conclusion: Both Sucralfate and Lidocain: antacid 50:50 solutions are effective in relieving the post EVBL pain. However, no statistically significant difference in duration of pain relief was detected in separate groups of patients treated with either treatment. PMID:27648035

  3. Occurrence of infective endocarditis following endoscopic variceal ligation therapy

    PubMed Central

    Zhang, Xuan; Liu, Xiaoli; Yang, Meifang; Dong, Huihui; Xv, Lichen; Li, Lanjuan

    2016-01-01

    Abstract Background: Endoscopic variceal ligation (EVL) is the endoscopic treatment of acute esophageal variceal hemorrhage, however, prophylaxis antibiotic during EVL is controversial. Methods: We reported a 60-year-old man with diabetes, liver cirrhosis and hepatocellular carcinoma who received EVL for esophageal variceal haemorrhage. Results: On the second day after EVL, the patient developed fever and chills. A week after EVL, the blood cultures were viridans streptococcus positive, and echocardiogram showed a vegetation on the cardiac valve. The patient was therefore diagnosed with infective endocarditis (IE). The patient was cured after 7 weeks of intravenous piperacillin sulbactam sodium. No complications were observed during the 3-month follow-up after discharge. Conclusion: To our knowledge, this is the first documented case to report IE caused by viridans streptococcus after EVL. Therefore, whether prophylaxis antibiotic should be administered to cirrhotic patients receiving EVL is worth further research. PMID:27583858

  4. A randomized control trial of bi-monthly versus bi-weekly endoscopic variceal ligation of esophageal varices.

    PubMed

    Yoshida, Hiroshi; Mamada, Yasuhiro; Taniai, Nobuhiko; Yamamoto, Kazuhito; Kawano, Youichi; Mizuguchi, Yoshiaki; Shimizu, Tetsuya; Takahashi, Tsubasa; Tajiri, Takashi

    2005-09-01

    Endoscopic variceal ligation (EVL) is a safe and simple procedure now being used on a widening scale. Yet most patients who undergo endoscopic treatment for esophageal varices eventually require additional treatment for recurrent varices. In this study, we investigated and compared the efficacy and long-term results of EVL performed in three treatments with a total of sixteen O-rings at two different intervals; bi-weekly (once every 2 wk: the conventional interval) and bi-monthly (once every 2 months). A total of 63 patients with esophageal varices were randomly assigned to groups receiving bi-weekly or bi-monthly EVL treatment. Optimal medical therapy was assessed by one medical doctor who was unaware of the patients' treatment assignments. Three parameters of treatment outcome were evaluated: the rate of recurrence, rate of additional treatment, and overall survival. The overall rates of variceal recurrence and additional treatment were both higher in the bi-weekly group than in the bi-monthly group (p < 0.001). In conclusion, EVL performed for the treatment of esophageal varices at bi-monthly intervals brought about better results than the same treatment performed at bi-weekly intervals. The treatments intercalated by the longer interval obtained a higher total eradication rate, lower recurrence rate, and lower rate of additional treatment. PMID:16128945

  5. Cyanoacrylate Injection Versus Band Ligation in the Endoscopic Management of Acute Gastric Variceal Bleeding

    PubMed Central

    Qiao, Weiguang; Ren, Yutang; Bai, Yang; Liu, Side; Zhang, Qiang; Zhi, Fachao

    2015-01-01

    Abstract The evidence for optimal endoscopic management of bleeding gastric varices is lacking. The clinical outcome is controversial in trials comparing cyanoacrylate injection and band ligation. To help guide endoscopic decisions regarding acute gastric variceal bleeding, a meta-analysis was conducted. Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and ScienceDirect were searched for all randomized controlled trials (RCTs) containing the 2 interventions. The main outcomes evaluated in the meta-analysis were active bleeding control, blood transfusion, rebleeding, recurrence of varices, complications, and survival. Three RCTs were identified, which included 194 patients with active gastric variceal bleeding from Taiwan and Romania. Active bleeding control was achieved in 46 of 49 (93.9%) patients in the cyanoacrylate injection group, compared with 35 of 44 (79.5%) in the band ligation group (P = 0.032), for a pooled odds ratio of 4.44 (95% confidence interval, 1.14–17.30). Rebleeding rate was comparable in type 2 gastroesophageal varices (GOV2) between the 2 interventions (35.7% vs 34.8%, P = 0.895), but cyanoacrylate injection seemed superior for reducing rebleeding rate in type 1 gastroesophageal varices (GOV1, 26.1% vs 47.7%, P = 0.035) and type 1 isolated gastric varices (IGV1, 17.6% vs 85.7%, P = 0.015). Cyanoacrylate injection was also superior in controlling recurrence of gastric varices to band ligation (36.0% vs 66.0%, P = 0.002). There was no difference in complications or mortality between the 2 interventions. The major limitation of this meta-analysis is the small number of studies/patients included. Compared with band ligation, injection cyanocrylate have an advantage in the control of acute gastric variceal bleeding, also with lower recurrence rate and rebleeding (except GOV2). The limited amount of studies included attenuates the strength of this meta-analysis; therefore, more high-quality RCTs are needed. PMID

  6. Efficacy of endoscopic variceal ligation for bleeding esophageal varices in patients with tumor thrombus of the portal vein trunk (Vp3) associated with hepatocellular carcinoma.

    PubMed

    Kokubu, S; Matsumoto, Y; Murakami, M; Shibata, H; Saigenji, K

    1997-04-01

    We studied the efficacy of endoscopic variceal ligation (EVL) in 16 patients with tumor thrombus of the portal vein trunk (Vp3) associated with hepatocellular carcinoma. The average (+/-SD) number of O rings used was 9.0 +/- 5.0 for the esophageal varices (n = 7) and 16.4 +/- 4.5 for the esophagogastric varices (n = 9). The variceal size was quickly reduced in 11 of the 13 cases whose therapeutic outcome was able to be assessed by endoscopy. The red color sign improved in 10 of the 13 cases, but the therapeutic end point (F0, RC-) was achieved in only two patients, who were also treated by endoscopic injection sclerotherapy. Emergency EVL achieved only short-term survival (17.14 +/- 6.64 days) and transient hemostasis. Elective EVL was associated with a survival duration of 90.0 +/- 64.25 days. The difference in the survival rate between emergency and elective cases was significant (P < .05). With regard to the timing of its application, EVL, being a less-invasive treatment, should be performed electively before variceal rebleeding for those patients with Vp3 hepatocellular carcinoma whose liver function is preserved. PMID:9151930

  7. Proton Pump Inhibitor Therapy Is Associated With Reduction of Early Bleeding Risk After Prophylactic Endoscopic Variceal Band Ligation

    PubMed Central

    Kang, Seong Hee; Yim, Hyung Joon; Kim, Seung Young; Suh, Sang Jun; Hyun, Jong Jin; Jung, Sung Woo; Jung, Young Kul; Koo, Ja Seol; Lee, Sang Woo

    2016-01-01

    Abstract Endoscopic variceal band ligation (EVL) is an effective procedure to control and prevent variceal bleeding in patients with liver cirrhosis, but it can be complicated by bleeding from post-EVL ulcers. Several studies have reported that proton pump inhibitors (PPIs) decrease the size of post-EVL ulcers. However, evidence are limited as to whether PPIs actually reduce the risk of bleeding after EVL. This study aimed to analyze the factors associated with bleeding after prophylactic EVL and to assess the effect of PPI therapy. Five hundred and five cirrhotic patients with high risk esophageal varices who received primary prophylactic EVL were included for this retrospective cohort study. Post-EVL bleeding was defined as bleeding after prophylactic EVL within 8 weeks evidenced by the occurrence of melena or hematemesis, or by a decrease of hemoglobin by >2.0 g/dL. If evidence of bleeding from ulceration of the EVL sites was confirmed by endoscopy, we defined it as post-EVL ulcer bleeding. Fourteen patients developed bleeding after prophylactic EVL. Factors associated with post-EVL bleeding included alcohol as etiology, low albumin, high total bilirubin, high Child-Pugh score, high MELD score, coexistence of gastric varices, and not administrating PPI medication by univariate analysis. In multivariate logistic analysis, Co-existing gastric varix (odds ratio [OR] 5.680, P = 0.005] and not administrating PPIs (OR 8.217, P = 0.002) were associated with bleeding after prophylactic EVL. In the subgroup analysis excluding patients whose gastric varices were treated, not administering PPI medication (OR 8.827, P = 0.008) was the sole factor associated with post-EVL bleeding. We suggest that PPI therapy needs to be considered in patients receiving prophylactic EVL to reduce the risk of bleeding after prophylactic EVL. PMID:26937932

  8. Band ligation vs. N-Butyl-2-cyanoacrylate injection in acute gastric variceal bleeding: a prospective follow-up study.

    PubMed

    Tantau, Marcel; Crisan, Dana; Popa, Daniel; Vesa, Stefan; Tantau, Alina

    BACKGROUND. Treatment of gastric varices (GV) implies a number of several difficulties and sometimes entails complications. The best endoscopic success rate was attributed until now to the use of tissue adhesives(N-Butyl-2-Cyanoacrylate) and band ligation. AIM. To assess the therapeutic efficacy and safety of cyanoacrylate injection compared to band ligation in patients with acute GV hemorrhage. MATERIAL AND METHODS. Thirty-seven patients with upper gastrointestinal bleeding from GV were included in the study, treated with cyanoacrylate injection (GVO)-19 patients or band ligations (GVL)-18 patients. They were followed up for overall results, complications and survival rate. RESULTS. The mean age of the study group was 60.22 ± 9.34 years, with a male/female ratio of 21:16. The mean follow-up period was 427.26 ± 214.16 days in the GVO group and 406.21 ± 213.23 days in the GVL group (p = 0.76). Initial hemostasis was achieved in all patients treated with cyanoacrylate and in 88.88% from the GVL group (p = 0.43). Rebleeding occurred in 72.22% of the GVL group and in 31.57% of the GVO patients (p = 0.03). Patients in the GVO group had a significantly larger rebleeding-free period(p = 0.006). No difference was found in survival rates(p = 0.75). The Child Class (p = 0.003 for Class C) and treatment method (p = 0.01) were independently associated with the rate of rebleeding. No differences were found regarding the rate of complications. CONCLUSION. The use of cyanoacrylate in acute GV bleeding had better results when compared with band ligation in terms of controlling the hemorrhage and recurrence of bleeding. The overall survival rate was not influenced by the method used for the treatment of complicated GV.

  9. Addition of Somatostatin After Successful Endoscopic Variceal Ligation Does not Prevent Early Rebleeding in Comparison to Placebo: A Double Blind Randomized Controlled Trial

    PubMed Central

    Kumar, Ashish; Jha, Sanjeev K.; Mittal, Vibhu V.; Sharma, Praveen; Sharma, Barjesh C.; Sarin, Shiv K.

    2015-01-01

    Background Efficacy of endoscopic sclerotherapy in controlling acute variceal bleeding is significantly improved when vasoactive drug is added. Endoscopic variceal ligation (EVL) is superior to sclerotherapy. Whether efficacy of EVL will also improve with addition of somatostatin is not known. We compared EVL plus somatostatin versus EVL plus placebo in control of acute variceal bleeding. Methods Consecutive cirrhotic patients with acute esophageal variceal bleeding were enrolled. After emergency EVL, patients were randomized to receive either somatostatin (250 mcg/hr) or placebo infusion. Primary endpoint was treatment failure within 5 days. Treatment failure was defined as fresh hematemesis ≥2 h after start of therapy, or a 3 gm drop in Hb, or death. Results 61 patients were enrolled (EVL plus somatostatin group, n = 31 and EVL plus placebo group, n = 30). The baseline characteristics were similar. Within the initial 5-day period, the frequency of treatment failure was similar in both the groups (EVL plus somatostatin group 8/31 [26%] versus EVL plus placebo group 7/30 [23%]; P = 1.000). The mortality was also similar in the two groups (3/31 [10%] vs. 3/30 [10%]; P = 1.000). Baseline HVPG ≥19 mm Hg and active bleeding at index endoscopy were independent predictors of treatment failure. Conclusions Addition of somatostatin infusion to EVL therapy does not offer any advantage in control of acute variceal bleeding or reducing mortality. The reason for this may be its failure to maintain sustained reduction in portal pressure for five days. Active bleeding at index endoscopy and high baseline HVPG should help choose early alternative treatment options. Trial registered with ClincalTrials.gov vide NCT01267669. PMID:26628838

  10. Fatal Klebsiella pneumoniae meningitis and emphysematous brain abscess after endoscopic variceal ligation in a patient with liver cirrhosis and diabetes mellitus.

    PubMed

    Shih, Hsin-I; Lee, Hsin-Chun; Chuang, Chiao-Hsiung; Ko, Wen-Chien

    2006-10-01

    Procedure-related bacterial infections may complicate esophageal variceal ligation in cirrhosis patients. Here, we report a 58-year-old man with underlying diabetes and liver cirrhosis who developed Klebsiella pneumoniae meningitis and brain abscess with gas formation in brain parenchyma and ventricles after this procedure. Despite administration of appropriate antimicrobial therapy, he became comatose on the 3rd day of acute illness and died on the 4th day of hospitalization. This case highlights the indication for antimicrobial prophylaxis in cirrhotic patients with gastrointestinal bleeding, and the need for early and heightened awareness of central nervous system infections in cirrhotic patients with hepatic encephalopathy.

  11. Self-Expandable Metal Stents for Persisting Esophageal Variceal Bleeding after Band Ligation or Injection-Therapy: A Retrospective Study

    PubMed Central

    Müller, Martin; Seufferlein, Thomas; Perkhofer, Lukas; Wagner, Martin; Kleger, Alexander

    2015-01-01

    Background and Study Aims Despite a pronounced reduction of lethality rates due to upper gastrointestinal bleeding, esophageal variceal bleeding remains a challenge for the endoscopist and still accounts for a mortality rate of up to 40% within the first 6 weeks. A relevant proportion of patients with esophageal variceal bleeding remains refractory to standard therapy, thus making a call for additional tools to achieve hemostasis. Self-expandable metal stents (SEMS) incorporate such a tool. Methods We evaluated a total number of 582 patients admitted to our endoscopy unit with the diagnosis “gastrointestinal bleeding” according to our documentation software between 2011 and 2014. 82 patients suffered from esophageal variceal bleeding, out of which 11 cases were refractory to standard therapy leading to SEMS application. Patients with esophageal malignancy, fistula, or stricture and a non-esophageal variceal bleeding source were excluded from the analysis. A retrospective analysis reporting a series of clinically relevant parameters in combination with bleeding control rates and adverse events was performed. Results The initial bleeding control rate after SEMS application was 100%. Despite this success, we observed a 27% mortality rate within the first 42 days. All of these patients died due to non-directly hemorrhage-associated reasons. The majority of patients exhibited an extensive demand of medical care with prolonged hospital stay. Common complications were hepatic decompensation, pulmonary infection and decline of renal function. Interestingly, we found in 7 out of 11 patients (63.6%) stent dislocation at time of control endoscopy 24 h after hemostasis or at time of stent removal. The presence of hiatal hernia did not affect obviously stent dislocation rates. Refractory patients had significantly longer hospitalization times compared to non-refractory patients. Conclusions Self-expandable metal stents for esophageal variceal bleeding seem to be safe and

  12. Management of rectal varices in portal hypertension

    PubMed Central

    Al Khalloufi, Kawtar; Laiyemo, Adeyinka O

    2015-01-01

    Rectal varices are portosystemic collaterals that form as a complication of portal hypertension, their prevalence has been reported as high as 94% in patients with extrahepatic portal vein obstruction. The diagnosis is typically based on lower endoscopy (colonoscopy or sigmoidoscopy). However, endoscopic ultrasonography has been shown to be superior to endoscopy in diagnosing rectal varices. Color Doppler ultrasonography is a better method because it allows the calculation of the velocity of blood flow in the varices and can be used to predict the bleeding risk in the varices. Although rare, bleeding from rectal varices can be life threatening. The management of patients with rectal variceal bleeding is not well established. It is important to ensure hemodynamic stability with blood transfusion and to correct any coagulopathy prior to treating the bleeding varices. Endoscopic injection sclerotherapy has been reported to be more effective in the management of active bleeding from rectal varices with less rebleeding rate as compared to endoscopic band ligation. Transjugular intrahepatic portsystemic shunt alone or in combination with embolization is another method used successfully in control of bleeding. Balloon-occluded retrograde transvenous obliteration is an emerging procedure for management of gastric varices that has also been successfully used to treat bleeding rectal varices. Surgical procedures including suture ligation and porto-caval shunts are considered when other methods have failed. PMID:26730278

  13. [Orbital varices].

    PubMed

    Seceleanu, Andreea; Szabo, I; Călugăru, M; Dudea, S M; Preda, D

    2004-01-01

    The purpose of this study was to point out a case with orbital venous abnormalities at the left eye, associated with varices of the legs. The clinical picture of this case was: intermittent exophthalmos, venous malformations at the level of the lids and episclera, elevated ocular pressure. All this signs reveal an abnormality at the level of venous wall, indicating a constitutional weakness of the venous system. The case was investigated by imagistic methods: ultrasound examination, Doppler -ultrasound and magnetic resonance imaging. According to the facts offered by clinical and imagistic investigation this case can be included into the first type of orbital varices, associated with secondary glaucoma provoked by an elevated episcleral venous pressure. PMID:15598045

  14. Challenges of banding jejunal varices in an 8-year-old child

    PubMed Central

    Belsha, Dalia; Thomson, Mike

    2015-01-01

    Endoscoic variceal ligation (EVL) by the application of bands on small bowel varices is a relatively rare procedure in gastroenterology and hepatology. There are no previously reported paediatric cases of EVL for jejunal varices. We report a case of an eight-year-old male patient with a complex surgical background leading to jejunal varices and short bowel syndrome, presenting with obscure but profound acute gastrointestinal bleeding. Wireless capsule endoscopy and double balloon enteroscopy (DBE) confirmed jejunal varices as the source of bleeding. The commercially available variceal banding devices are not long enough to be used either with DBE or with push enteroscopes. With the use of an operating gastroscope, four bands were placed successfully on the afferent and efferent ends of the leads of the 2 of the varices. Initial hemostasis was achieved with obliteration of the varices after three separate applications. This case illustrates the feasibility of achieving initial hemostasis in the pediatric population. PMID:26722617

  15. Embolization of Bleeding Stomal Varices by Direct Percutaneous Approach

    SciTech Connect

    Arulraj, Ramakrishnan; Mangat, Kamarjit S.; Tripathi, Dhiraj

    2011-02-15

    Stomal varices can occur in patients with stoma in the presence of portal hypertension. Suture ligation, sclerotherapy, angiographic embolization, stoma revision, beta blockade, portosystemic shunt, and liver transplantation have been described as therapeutic options for bleeding stomal varices. We report the case of a 21-year-old patient with primary sclerosing cholangitis and colectomy with ileostomy for ulcerative colitis, where stomal variceal bleeding was successfully treated by direct percutaneous embolization. We consider percutaneous embolization to be an effective way of treating acute stomal bleeding in decompensated patients while awaiting decisions regarding shunt procedures or liver transplantation.

  16. Noninvasive predictors of presence and grade of esophageal varices in viral cirrhotic patients.

    PubMed

    Nada, Lahmidani; Samira, El Fakir; Bahija, Benyachou; Adil, Ibrahimi; Nourdine, Aqodad

    2015-01-01

    Predicting the presence and the grade of varices by non-invasive methods is likely to predict the need for prophylactic beta blockers or endoscopic variceal ligation. The factors related to the presence of varices are not well-defined. Therefore, the present study has been undertaken to determine the appropriateness of the various factors in predicting the existence and also the grade of esophageal varices. Patients with diagnosis of liver cirrhosis due to hepatitis C or B were included in a retrospective study between January 2001 and January 2010. All the patients underwent detailed clinical evaluation, appropriate investigations, imaging studies (ultrasound with Doppler) and endoscopy at our center. Five variables considered relevant to the presence and grade of varices were tested using univariate and multivariate analysis (logistic regression). Three hundred and seventy two patients with viral liver cirrhosis were included, with 192 (51.6%) males. Platelet count and abundance of ascites were significantly associated with the presence of esophageal varices. However, abundance of ascites, prothrombin time, diameter of the spleen and portal vein were significantly associated with a large varice. In multivariate analysis, platelet count inferior to 100000 was associated with presence of varices (p = 0.04) and only abundance of ascites was associated with large varice. Low Platelet count (< or equal 100000) is associated with the presence of varices in viral cirrhotic patients and abundance of ascites is correlated with the presence of large varices.

  17. Colorectal variceal bleeding in patients with extrahepatic portal vein thrombosis and idiopathic portal hypertension.

    PubMed

    Orozco, H; Takahashi, T; Mercado, M A; Prado-Orozco, E; Ferral, H; Hernandez-Ortiz, J; Esquivel, E

    1992-03-01

    We report three patients with colonic variceal bleeding secondary to portal hypertension, 0.5% of all cases with hemorrhagic portal hypertension studied by us in the last 16 years. One patient had idiopathic portal hypertension, and the others had extrahepatic portal vein thrombosis. Colonic varices were documented in all three cases by angiogram; large arteriovenous fistulas in the territory of the superior mesenteric artery and between the inferior mesenteric artery and hemorrhoidal veins were demonstrated in one patient. Two patients underwent colonoscopy; colonic varices were seen in only one. Two patients also had bled from esophagogastric varices. One patient underwent descending colon and sigmoid resection after failure to control bleeding with ligation of arterial supply; one patient underwent the Sugiura procedure, plus transanal ligation of hemorrhoids and rectal varices. At 3 months, 2 years, and 4 years of follow-up, the patients were in good general condition without any evidence of rebleeding.

  18. Tubal ligation

    MedlinePlus

    ... tying; Tying the tubes; Hysteroscopic tubal occlusion procedure; Contraception - tubal ligation; Family planning - tubal ligation ... Tubal ligation is considered a permanent form of birth control. It is NOT recommended as a short-term ...

  19. Bleeding esophageal varices

    MedlinePlus

    ... air. This produces pressure against the bleeding veins (balloon tamponade). Once the bleeding is stopped, other varices can be treated with medicines and medical procedures to prevent future bleeding, including: Drugs called ...

  20. Downhill Esophageal Varices Associated With Central Venous Catheter-Related Thrombosis Managed With Endoscopic and Surgical Therapy

    PubMed Central

    Berkowitz, Joshua C.; Bhusal, Sushma; Desai, Deepak; Cerulli, Maurice A.

    2016-01-01

    Downhill esophageal varices are a rare cause of upper gastrointestinal hemorrhage. We present a case of downhill variceal bleeding due to superior vena cava thrombosis resulting from a prior central venous catheter. The patient was managed with endoscopic band ligation and later with surgical axillary vein to right atrium bypass grafting. Successful long-term resolution of varices was achieved at 1 year of follow-up. This is the longest follow-up described for combined endoscopic and surgical management in the existing literature for catheter-associated downhill varices. PMID:27807564

  1. Low risk of bacteremia after endoscopic variceal therapy for esophageal varices: a systematic review and meta-analysis

    PubMed Central

    Jia, Yi; Dwivedi, Alok; Elhanafi, Sherif; Ortiz, Arleen; Othman, Mohamed; Zuckerman, Marc

    2015-01-01

    Background and study aims: Endoscopic variceal ligation (EVL) and endoscopic variceal sclerotherapy (EVS) are the main therapeutic procedures for the emergency treatment and secondary prophylaxis of esophageal varices in cirrhotics. Post-endoscopic bacteremia has been reported after EVS and EVL, but data on the frequency of bacteremia are conflicting. This study aims to provide incidences of bacteremia after EVS and EVL in different settings through meta-analysis. Methods: Only prospective or randomized studies were included in this meta-analysis. Binomial distribution was used to compute variance for each study. Random effects models were used as the final model for estimating the effect size and 95 % confidence interval. Adjusted effects were obtained using meta-regression analysis. Results: Nineteen prospective studies involving 1001 procedures in 587 patients were included in the meta-analysis on the risk of bacteremia after EVS or EVL in cirrhotics with esophageal varices. The frequency of bacteremia after endoscopic variceal therapy was 13 %. The frequency of bacteremia after EVS (17 %) was higher than after EVL (6 %) with no statistically significant difference (P = 0.106). The frequency of bacteremia after elective EVS (14 %) was significantly less than after emergency EVS (22 %) (P < 0.001). The frequency of bacteremia after elective EVL (7.6 %) was not significantly different from after emergency EVL (3.2 %) (P = 0.850). Conclusions: The incidence of bacteremia is low in patients with cirrhosis and varices after esophageal variceal therapy. These results are consistent with our current guidelines that antibiotic prophylaxis before endoscopic variceal therapy is only necessary for bleeding patients. PMID:26528494

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

    PubMed

    Myung, Dae-Seong; Chung, Cho-Yun; Park, Hyung-Chul; Kim, Jong-Sun; Cho, Sung-Bum; Lee, Wan-Sik; Choi, Sung-Kyu; Joo, Young-Eun

    2013-09-14

    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.

  3. Tubal Ligation

    MedlinePlus

    Tubal ligation (getting your "tubes tied") is a type of surgery. It prevents a woman from getting pregnant. ... to most normal activities within a few days. Tubal ligation can sometimes be reversed, but not always.

  4. Management of acute variceal bleeding using hemostatic powder

    PubMed Central

    El-Mikkawy, Ahmed; Abdalla, Haitham; Mostafa, Ibrahim; Devière, Jacques

    2015-01-01

    Background and objectives This study aimed to test the safety and efficacy of Hemospray® for emergency control of acute variceal bleeding (AVB) due to portal hypertension in cirrhotic patients. Patients and methods This single-arm, prospective trial, conducted at two hospitals in Belgium and Egypt, included patients admitted to the emergency room with hematemesis and/or melena and known or suspected liver cirrhosis. All patients received urgent hemodynamic stabilization, octreotide (50 mcg bolus then 25 mcg/hour for 24 hours) and intravenous ceftriaxone (1 g/hour). Endoscopy to confirm AVB and Hemospray® application (if indicated) was performed within six hours of admission. Patients were kept under observation for 24 hours and underwent second endoscopy and definitive therapy (band ligation and/or cyanoacrylate injection in cases of gastric varices) the next day. Results Thirty-eight patients were admitted for suspected AVB, and 30 of these had confirmed AVB (70% male; mean age 59.5 years (range, 32.0–73 years)). Child-Pugh class C liver disease was present in 53.4%. Esophageal varices were observed in 83.4% of patients, gastric varices in 10%, and duodenal varices in 6.6%. Spurting bleeding at the time of endoscopy was observed in 43.4%. One patient developed hematemesis six hours after Hemospray® application and underwent emergency endoscopic band ligation. No major adverse events or mortalities were observed during 15-day follow-up. Conclusion Hemospray® application was safe and effective at short-term follow-up for emergency treatment of AVB in cirrhotic patients. PMID:26137303

  5. [Two cases of esophageal variceal rupture associated with chemotherapy for liver metastasis of breast cancer].

    PubMed

    Mizuyama, Yoko; Shinto, Osamu; Matsutani, Sinji; Arimoto, Yuichi; Nakagawa, Hiroji; Ohno, Yoshioki; Takashima, Tsutomu

    2014-11-01

    A morphological change resembling liver cirrhosis called pseudocirrhosis may be observed following chemotherapy for liver metastasis of breast cancer. Pseudocirrhosis is hypothesized to be caused by retraction of the hepatic capsule along with tumor shrinkage and subsequent scar formation around the metastatic lesion, as a response to the infiltrating tumor or chemotherapy-induced hepatic injury. The progression of cirrhotic changes may result in portal hypertension and esophageal varices. We managed two cases of esophageal variceal rupture during chemotherapy for breast cancer with liver metastasis. Hemostasis was successfully achieved by the endoscopic variceal ligation technique in both cases. We conclude that clinicians should be aware of the risk of pseudocirrhosis during chemotherapy for liver metastasis, and a periodic endoscopic follow-up is recommended along with appropriate management of esophageal varices.

  6. Pharmacologic influence on esophageal varices

    SciTech Connect

    Lunderquist, A.; Owman, T.; Alwmark, A.; Gullstrand, P.; Hall-Angeras, M.; Joelsson, B.; Tranberg, K.G.; Pettersson, K.I.

    1983-06-01

    Selective catherization of the left gastric vein was performed after percutaneous transhepatic portography (PTP) in patients with portal hypertension and esophageal varices. Following the hypothesis that drugs increasing the lower esophageal sphincter (LES) pressure may obstruct the variceal blood flow throught the lower esophagus, the effect of different drugs (i.e., intravenous injection of vasopressin, pentagastrin, domperidone and somatostatin and subcutaneous injection of metacholine) on the variceal blood flow was examined. Vasopressin did not change the variceal blood flow; pentagastrine, with its known effect of increasing the LES pressure produced a total interruption of the flow in four of eight patients; domperiodone, also known to increase the LES pressure obstructed the variceal blood flow in the only patient examined with this drug; somatostatin has no reported action on the LES but blocked the flow in one of two patients; and metacholine, reported to increase the LES pressure did not produce any change in the flow in the three patients examined. LES pressure was recorded before and during vasopressin infusion in seven patients with portal hypertension and esophageal varices. No reaction on the pressure was found. The patient number in the study is small and the results are nonuniform but still they suggest that drugs increasing the LES tonus might be useful to control variceal blood flow.

  7. [Case of cardial varices rupture due to danaparoid sodium with portal venous thrombosis].

    PubMed

    Kawaratani, Hideto; Matsumura, Masahiko; Tsujimoto, Tatsuhiro; Morimoto, Tomoko; Kitade, Mitsuteru; Umemoto, Norie; Sakai, Kyouko; Fukui, Hiroshi

    2008-12-01

    A 54-year-old man had been admitted to Nara city hospital because of hematemesis and dyspnea caused by physical exertion, and was given a diagnosis of esophago-cardial varices and portal venous thrombosis. He was transferred to our hospital for further examinations and treatments. Ultrasonography (US) and computed tomography (CT) revealed the progression of portal venous thrombosis. Danaparoid sodium was administered to treat the portal vein thrombus. 5 days later, the patient was found to have hematemesis resulting from a cardial varices rupture. After endoscopic variceal ligation (EVL) and endoscopic injection sclerotherapy (EIS) was performed, danaparoid sodium was administered for 2 weeks. After the treatment, portal vein thrombus had almost disappeared. Due to an increased risk of bleeding, cases of esophago-cardial varices with portal venous thrombosis must be treated with care. This is the first report of upper gastrointestinal bleeding due to danaparoid sodium. Danaparoid sodium must be carefully administered when patients have portal venous thrombosis with delicate varices. PMID:19057161

  8. Endoscopic treatment for esophageal varices complicated by Isaacs' syndrome involving difficulty with conventional sedation.

    PubMed

    Suzuki, Yuhei; Yamazaki, Yuichi; Hashizume, Hiroaki; Kobayashi, Takeshi; Ohyama, Tatsuya; Horiguchi, Norio; Sato, Ken; Kakizaki, Satoru; Kusano, Motoyasu; Yamada, Masanobu

    2016-02-01

    A 54-year-old male consulted a local doctor with a chief complaint of systemic convulsions and muscle stiffness and was diagnosed with Isaacs' syndrome based on positive findings for antibodies against voltage-gated potassium channels in 2009. He subsequently experienced repeated hematemesis in 2013, at which time he was taken to our hospital by ambulance. Emergent endoscopy revealed esophageal varices with spurting bleeding. The bleeding was stopped with urgent endoscopic variceal ligation. Three days later, the patient developed sudden dyspnea with stridor during inspiration under sedation with an intravenous injection of low-dose flunitrazepam prior to receiving additional treatment and was aroused with intravenous flumazenil, after which his dyspnea immediately improved. Dyspnea may be induced by muscle cramps associated with Isaacs' syndrome exacerbated by sedation. Endoscopic variceal ligation was performed safely using multiple ligation devices in an awake state following pre-medication with hydroxyzine, without sudden dyspnea. Endoscopists should be cautious of the use of sedatives in patients with diseases associated with muscle twitching or stiffness, as in the current case. In addition, it is necessary to administer endoscopic treatment in an awake state or under conscious sedation in patients with a high risk of dyspnea. PMID:26862027

  9. Chemoselective ligation

    DOEpatents

    Saxon, Eliana; Bertozzi, Carolyn R.

    2011-04-12

    The present invention features a chemoselective ligation reaction that can be carried out under physiological conditions. In general, the invention involves condensation of a specifically engineered phosphine, which can provide for formation of an amide bond between the two reactive partners resulting in a final product comprising a phosphine moiety, or which can be engineered to comprise a cleavable linker so that a substituent of the phosphine is transferred to the azide, releasing an oxidized phosphine byproduct and producing a native amide bond in the final product. The selectivity of the reaction and its compatibility with aqueous environments provides for its application in vivo (e.g., on the cell surface or intracellularly) and in vitro (e.g., synthesis of peptides and other polymers, production of modified (e.g., labeled) amino acids).

  10. Chemoselective ligation

    DOEpatents

    Saxon, Eliana; Bertozzi, Carolyn Ruth

    2011-12-13

    The present invention features a chemoselective ligation reaction that can be carried out under physiological conditions. In general, the invention involves condensation of a specifically engineered phosphine, which can provide for formation of an amide bond between the two reactive partners resulting in a final product comprising a phosphine moiety, or which can be engineered to comprise a cleavable linker so that a substituent of the phosphine is transferred to the azide, releasing an oxidized phosphine byproduct and producing a native amide bond in the final product. The selectivity of the reaction and its compatibility with aqueous environments provides for its application in vivo (e.g., on the cell surface or intracellularly) and in vitro (e.g., synthesis of peptides and other polymers, production of modified (e.g., labeled) amino acids).

  11. Chemoselective ligation

    DOEpatents

    Saxon, Eliana; Bertozzi, Carolyn Ruth

    2010-11-23

    The present invention features a chemoselective ligation reaction that can be carried out under physiological conditions. In general, the invention involves condensation of a specifically engineered phosphine, which can provide for formation of an amide bond between the two reactive partners resulting in a final product comprising a phosphine moiety, or which can be engineered to comprise a cleavable linker so that a substituent of the phosphine is transferred to the azide, releasing an oxidized phosphine byproduct and producing a native amide bond in the final product. The selectivity of the reaction and its compatibility with aqueous environments provides for its application in vivo (e.g., on the cell surface or intracellularly) and in vitro (e.g., synthesis of peptides and other polymers, production of modified (e.g., labeled) amino acids).

  12. Chemoselective ligation

    DOEpatents

    Saxon, Eliana; Bertozzi, Carolyn

    2003-05-27

    The present invention features a chemoselective ligation reaction that can be carried out under physiological conditions. In general, the invention involves condensation of a specifically engineered phosphine, which can provide for formation of an amide bond between the two reactive partners resulting in a final product comprising a phosphine moiety, or which can be engineered to comprise a cleavable linker so that a substituent of the phosphine is transferred to the azide, releasing an oxidized phosphine byproduct and producing a native amide bond in the final product. The selectivity of the reaction and its compatibility with aqueous environments provides for its application in vivo (e.g., on the cell surface or intracellularly) and in vitro (e.g., synthesis of peptides and other polymers, production of modified (e.g., labeled) amino acids).

  13. Chemoselective ligation

    DOEpatents

    Saxon, Eliana; Bertozzi, Carolyn R.

    2011-05-10

    The present invention features a chemoselective ligation reaction that can be carried out under physiological conditions. In general, the invention involves condensation of a specifically engineered phosphine, which can provide for formation of an amide bond between the two reactive partners resulting in a final product comprising a phosphine moiety, or which can be engineered to comprise a cleavable linker so that a substituent of the phosphine is transferred to the azide, releasing an oxidized phosphine byproduct and producing a native amide bond in the final product. The selectivity of the reaction and its compatibility with aqueous environments provides for its application in vivo (e.g., on the cell surface or intracellularly) and in vitro (e.g., synthesis of peptides and other polymers, production of modified (e.g., labeled) amino acids).

  14. Chemoselective ligation

    DOEpatents

    Saxon, Eliana; Bertozzi, Carolyn R.

    2010-02-23

    The present invention features a chemoselective ligation reaction that can be carried out under physiological conditions. In general, the invention involves condensation of a specifically engineered phosphine, which can provide for formation of an amide bond between the two reactive partners resulting in a final product comprising a phosphine moiety, or which can be engineered to comprise a cleavable linker so that a substituent of the phosphine is transferred to the azide, releasing an oxidized phosphine byproduct and producing a native amide bond in the final product. The selectivity of the reaction and its compatibility with aqueous environments provides for its application in vivo (e.g. on the cell surface or intracellularly) and in vitro (e.g., synthesis of peptides and other polymers, production of modified (e.g., labeled) amino acids).

  15. Chemoselective ligation

    DOEpatents

    Saxon, Eliana; Bertozzi, Carolyn

    2006-10-17

    The present invention features a chemoselective ligation reaction that can be carried out under physiological conditions. In general, the invention involves condensation of a specifically engineered phosphine, which can provide for formation of an amide bond between the two reactive partners resulting in a final product comprising a phosphine moiety, or which can be engineered to comprise a cleavable linker so that a substituent of the phosphine is transferred to the azide, releasing an oxidized phosphine byproduct and producing a native amide bond in the final product. The selectivity of the reaction and its compatibility with aqueous environments provides for its application in vivo (e.g., on the cell surface or intracellularly) and in vitro (e.g., synthesis of peptides and other polymers, production of modified (e.g., labeled) amino acids).

  16. Gastric varices: Classification, endoscopic and ultrasonographic management

    PubMed Central

    Wani, Zeeshan Ahmad; Bhat, Riyaz Ahmad; Bhadoria, Ajeet Singh; Maiwall, Rakhi; Choudhury, Ashok

    2015-01-01

    Gastric varices (GV) are responsible for 10-30% of all variceal hemorrhage. However, they tend to bleed more severely with higher mortality. Around 35-90% rebleed after spontaneous hemostasis. Approximately 50% of patients with cirrhosis of liver harbor gastroesophageal varices. In this review, new treatment modalities in the form of endoscopic treatment options and interventional radiological procedures have been discussed besides discussion on classification and pathophysiology of GV. PMID:26958057

  17. Multiple esophageal variceal ruptures with massive ascites due to myelofibrosis-induced portal hypertension

    PubMed Central

    Tokai, Koichi; Miyatani, Hiroyuki; Yoshida, Yukio; Yamada, Shigeki

    2012-01-01

    A 75-year old man had been diagnosed at 42 years of age as having polycythemia vera and had been monitored at another hospital. Progression of anemia had been recognized at about age 70, and the patient was thus referred to our center in 2008 where secondary myelofibrosis was diagnosed based on bone marrow biopsy findings. Hematemesis due to rupture of esophageal varices occurred in January and February of 2011. The bleeding was stopped by endoscopic variceal ligation. Furthermore, in March of the same year, hematemesis recurred and the patient was transported to our center. He was in irreversible hemorrhagic shock and died. The autopsy showed severe bone marrow fibrosis with mainly argyrophilic fibers, an observation consistent with myelofibrosis. The liver weighed 1856 g the spleen 1572 g, indicating marked hepatosplenomegaly. The liver and spleen both showed extramedullary hemopoiesis. Myelofibrosis is often complicated by portal hypertension and is occasionally associated with gastrointestinal hemorrhage due to esophageal varices. A patient diagnosed as having myelofibrosis needs to be screened for esophageal/gastric varices. Myelofibrosis has a poor prognosis. Therefore, it is necessary to carefully decide the therapeutic strategy in consideration of the patient’s concomitant conditions, treatment invasiveness and quality of life. PMID:22851873

  18. Bleeding varices: 1. Emergency management.

    PubMed Central

    Hanna, S S; Warren, W D; Galambos, J T; Millikan, W J

    1981-01-01

    The aim of the emergency management of bleeding varices is to stop the hemorrhage nonoperatively if possible, avoiding emergency shunt surgery, an operation that has a higher mortality than elective shunt surgery. Patients with an upper gastrointestinal hemorrhage should undergo endoscopy immediately to verify the diagnosis of bleeding varices. They can then be categorized according to whether they stop bleeding spontaneously (group 1), continue to bleed slowly (group 2) or continue to bleed rapidly (group 3). Group 1 patients are discussed in the second part of this two-part series. Group 2 patients are initially treated with vasopressin given intravenously; those who fail to respond should undergo emergency angiography and receive vasopressin intra-arterially. If this fails, patients at low surgical risk should undergo urgent shunt surgery; those at high risk do better with endoscopic sclerotherapy. Group 3 patients are also given an intravenous infusion of vasopressin. Patients at low surgical risk who continue to bleed then receive tamponade with a Sengstaken--Blakemore tube. If this fails, they undergo emergency creation of an H-shaped mesocaval shunt. Patients at high surgical risk who fail to respond to vasopressin given intravenously are next treated intra-arterially. If this fails they are given either endoscopic or transhepatic sclerotherapy. PMID:7006779

  19. Successful Management of Neobladder Variceal Bleeding.

    PubMed

    Atwal, Dinesh; Chatterjee, Kshitij; Osborne, Scott; Kakkera, Krishna; Deas, Steven; Li, Ruizong; Erbland, Marcia

    2016-10-01

    Hematuria from a neobladder can occur due to a variety of pathologies including tumors, stones, and fistulas. Variceal bleeding in a neobladder is a very rare condition with only one case reported in literature. We present a case of a patient with cirrhosis and portal hypertension and an ileocolic orthotopic neobladder presenting with hematuria. Computed tomographic angiography showed dilated varices around the neobladder which were successfully embolized. To the best of our knowledge, this is the first report case of variceal bleeding in a neobladder successfully managed with the combination of TIPS (transjugular intrahepatic portosystemic shunt) procedure and embolization.

  20. Endoscopic banding ligation can effectively remove the submucosal tumor

    PubMed Central

    Xia, Fei-Zhen; Shen, Zhe; Chen, Hong-Tan; Yu, Chao-Hui; Chen, Wei-Xing

    2015-01-01

    Endoscopic band ligation for variceal bleeding in cirrhosis has been proved its safety and efficacy. We tried to treat submucosal tumors the gastrointestinal (GI) tract by endoscopic band ligation. The aim of this study was to evaluate the efficacy and safety of endoscopic band ligation in the treatment of submucosal tumors of the GI tract. There are 29 patients (15 men, 14 women, age range: 25-67 years old) with 30 submucosal lesions of the GI tract, including 15 lesions in the esophagus, 14 lesions in the of stomach and 1 lesion in the duodenal bulb. The average maximum diameter of the lesions was 7.78 mm (range: 2.4-23.6 mm). All submucosal lesions were successfully removed by band ligation. There is no bleeding and perforation in all patients. No recurrence was observed for the one month following-up. Endoscopic band ligation promises could be considered as a safe and effective for the treatment submucosal tumors of the GI tract, especially for the diameter of tumor < 25 mm. PMID:25785162

  1. Implantation of self-expanding metal stent in the treatment of severe bleeding from esophageal ulcer after endoscopic band ligation.

    PubMed

    Mishin, I; Ghidirim, G; Dolghii, A; Bunic, G; Zastavnitsky, G

    2010-09-01

    Endoscopic variceal ligation is superior to sclerotherapy because of its lower rebleeding and complication rates. However, ligation may be associated with life-threatening bleeding from postbanding esophageal ulcer. We report a case of a 49-year-old male with massive hemorrhage from esophageal ulcer on 8th day after successful band ligation of bleeding esophageal varices caused by postviral liver cirrhosis (Child-Pugh class C). A removable polyurethane membrane-covered self-expanding metal stent (SX-ELLA stent Danis, 135 mm × 25 mm, ELLA-CS, Hradec-Kralove, Czech Republic) was inserted in ICU for preventing fatal hemorrhage. Complete hemostasis was achieved and stent was removed after 8 days without rebleeding or any complications. To the best of our knowledge, this is the first report in English literature regarding life-threatening hemorrhage from postbanding esophageal ulcer successfully treated by self-expanding metal stent in a patient with portal hypertension.

  2. Unintended Pulmonary Artery Ligation during PDA Ligation.

    PubMed

    Kim, Dohun; Kim, Si-Wook; Shin, Hong-Ju; Hong, Jong-Myeon; Lee, Ji Hyuk; Han, Heon-Seok

    2016-01-01

    A 10-day-old boy was transferred to our hospital due to tachypnea. Patent ductus arteriosus (PDA), 4.8 mm in diameter, with small ASD was diagnosed on echocardiography. Surgical ligation of the ductus was performed after failure of three cycles of ibuprofen. However, the ductus remained open on routine postoperative echocardiography on the second postoperative day, and chest CT revealed inadvertent ligation of the left pulmonary artery (LPA) rather than the PDA. Emergent operation successfully reopened the clipped LPA and ligated the ductus on the same (second postoperative) day.Mechanical ventilator support was weaned on postoperative day 21, and the baby was discharged on postoperative day 47 with a normal left lung shadow. PMID:27585199

  3. Bleeding Ectopic Varices as the First Manifestation of Portal Hypertension

    PubMed Central

    Sharma, Brij; Raina, Sujeet; Sharma, Rajesh

    2014-01-01

    Ectopic varices are defined as dilated portosystemic collateral veins in locations other than the gastroesophageal region. We present a case of recurrent upper gastrointestinal bleeding as the first manifestation of portal hypertension. We diagnosed ectopic duodenal varices without gastroesophageal varices on upper GI endoscopy and extrahepatic portal venous obstruction (EHPVO) on CT angiography and managed this case. PMID:25374725

  4. Scintigraphic demonstration of gastrointestinal bleeding due to mesenteric varices

    SciTech Connect

    Hansen, M.E.; Coleman, R.E. )

    1990-07-01

    Mesenteric varices can appear as massive, acute lower gastrointestinal bleeding. The small bowel or colon may be involved, varices usually developing at sites of previous surgery or inflammation in patients with portal hypertension. Two patients with alcoholic cirrhosis and protal hypertension presented with rectal bleeding. Tc-99m RBC studies demonstrated varices and extravasation into the adjacent bowel. The varices were documented by mesenteric angiography. Characteristic features of Tc-99m labeled RBC studies can identify mesenteric varices as the cause of intestinal bleeding and localize the abnormal vessels.

  5. Direct Percutaneous Embolization of Bleeding Stomal Varices

    SciTech Connect

    Naidu, Sailen G.; Castle, Erik P.; Kriegshauser, J. Scott; Huettl, Eric A.

    2010-02-15

    Stomal variceal bleeding can develop in patients with underlying cirrhosis and portal hypertension. Most patients are best treated with transjugular intrahepatic portosystemic shunt (TIPS) creation because this addresses the underlying problem of portal hypertension. However, some patients are not good candidates for TIPS creation because they have end-stage liver disease or encephalopathy. We describe such a patient who presented with recurrent bleeding stomal varices, which was successfully treated with percutaneous coil embolization. The patient had bleeding-free survival for 1 month before death from unrelated causes.

  6. Tubal ligation (image)

    MedlinePlus

    Surgical sterilization which permanently prevents the transport of the egg to the uterus by means of sealing the fallopian tubes is called tubal ligation, commonly called "having one's tubes tied". This operation ...

  7. Tubal ligation - discharge

    MedlinePlus

    ... Tubal sterilization - discharge; Tube tying - discharge; Tying the tubes - discharge; Contraception - tubal ... You had tubal ligation (or tying the tubes) surgery to close your fallopian tubes. These tubes connect the ovaries to the uterus. After tubal ...

  8. Gastric Varices: An Overview for the Gastroenterology Nurse.

    PubMed

    Dale, Cheryl

    2016-01-01

    Gastric varices can occur in as many as one-third of patients with portal hypertension. Within the nursing literature, however, articles focus on the management of esophageal varices and portal hypertensive gastrointestinal bleeding with few publications about management of gastric varices. Given the advancement in therapies, it is prudent for gastroenterology nurses to have an understanding of its management and treatment options. This article reviews the pathophysiology, classification, and management of patients with gastric varices and outlines the importance of the nurse's role in the education and ongoing care for this patient group. PMID:26825559

  9. Hepatic Angiosarcoma Associated with Esophageal Variceal Hemorrhage

    PubMed Central

    Ito, Zensho; Kajihara, Mikio; Kobayashi, Yasunobu; Kanai, Tomoya; Matsumoto, Yoshihiro; Takakura, Kazuki; Yukawa, Toyokazu; Ohkusa, Toshifumi; Koyama, Seita; Imazu, Hiroo; Arakawa, Hiroshi; Ohata, Mitsuru; Koido, Shigeo

    2016-01-01

    Primary hepatic angiosarcoma is a very rare malignancy with a poor prognosis. Because patients present with no specific symptoms, the cancer can grow undetected and most cases are diagnosed too late for resection. We present the case of a 78-year-old Japanese man admitted to our hospital with massive hematemesis and melena. A total gastrectomy had previously been performed on the patient to treat gastric cancer. Endoscopic injection sclerotherapy was performed to control the bleeding from varices over the anastomosis. Computed tomography revealed the presence of multiple atypical liver nodules in the enhanced image. Histological diagnosis of hepatic angiosarcoma was obtained by percutaneous ultrasound-guided liver biopsy. To our knowledge, this is the first report of a patient with hepatic angiosarcoma and acute variceal hemorrhage. PMID:27721730

  10. Echo-endoscopic analysis of variceal hemodynamics in patient with isolated gastric varices

    PubMed Central

    Imamura, HIdemichi; Irisawa, Atsushi; Shibukawa, Goro; Takagi, Tadayuki; Hikichi, Takuto; Obara, Katsutoshi; Ohira, Hiromasa

    2014-01-01

    Background: It is considered that gastric varices (GVs) which have the large form in endoscopic view should be treated because they are regarded as having high blood flow volume and the risky varices of hemorrhage. However, there is no data of the correlation among the endoscopic view, diameter of GV, and blood flow volume in GV. The aim of this study was to investigate whether GV diameter correlates to blood flow volume or not. In addition, the correlation between the endoscopic findings of GVs, patient status, and blood flow volume was assessed. Materials and Methods: In this study, 24 patients were enrolled. Variceal form and its location were observed using flexible GI endoscopes. Assessment of variceal form and location was according to Japanese society of portal hypertension. Then, the GV diameter (the maximum short axis), the GV flow velocity, and the GV flow volume were measured by echo-endoscope with curved linear array or with electronic radial array. Results: Nineteen of 24 enrolled patients were analyzed. There was strong correlation between the GV diameter and the GV flow volume (rs = 0.85, P < 0.01). No significant difference in the GV diameter and the GV flow volume was found between each location. However, there was no significant difference in the GV diameter between each variceal form. In addition, no significant difference was found among Child–Pugh classifications, and in cases associated with or without hepatocelluer carcinoma. Conclusions: Strong correlation was found between GV diameter and flow volume of GV, regardless of the location. However, since there was no significant difference in the GV diameter between each variceal form in endoscopic view, measuring GV diameter is important to understand its hemodynamics for further treatment. PMID:25485272

  11. Colonic varices demonstrated by technetium-99m red cell scintigraphy

    SciTech Connect

    Brill, D.R.

    1987-03-01

    Colonic varices is a rare condition, generally associated with portal hypertension, which normally presents as acute, severe, gastrointestinal blood loss. A case is presented in which the varicosities were observed serendipitously in a patient with a pancreatic tumor, in whom the bleeding was not variceal but due to two small unrelated gastric hemangiomas. The literature is reviewed and scintigraphic features described.

  12. Self ligating lingual appliance.

    PubMed

    Juneja, Pankaj; Chopra, S S; Jayan, B K

    2015-12-01

    Adult demand for orthodontics has grown considerably over the past 10 years propelling increased demand for Esthetic Orthodontics. Lingual appliances are a viable option toward providing Esthetic Orthodontics. The lingual surface of the teeth has a unique morphology that makes it difficult to place brackets in ideal positions. Indirect bonding has become the established methods of overcoming these discrepancies, along with the latest designs of self ligating brackets which offer more efficient mechanics and shorter treatment time. PMID:26843757

  13. [Low gastrointestinal bleeding due to ectopic varices as a result of adhesions].

    PubMed

    Perea García, J; Lago Oliver, J; Muñoz Jiménez, F; del Valle, E; Duque Pérez, C; Turégano Fuentes, F

    2000-01-01

    Portal hypertension frequently causes the appearance of porto-systemic shunts, such as esophageal varices and also, but with much less frequency, other atypical shunts known as ectopic varices. Despite their infrequency/rarity, ectopic varices can cause serious gastrointestinal bleeding. Intraabdominal adhesions, especially post-operative ones, promote their appearance. The therapeutic management of ectopic varices is initially the same as that for esophageal varices but surgical treatment is usually necessary as a diagnostic and therapeutic procedure. PMID:15324625

  14. Embolization of Large Gastric Varices Using Vena Cava Filter and Coils

    SciTech Connect

    Ford, Jason M.; Shah, Himanshu Stecker, Michael S.; Namyslowski, Jan

    2004-08-15

    A 40-year-old male with alcoholic cirrhosis and portal hypertension presented with acute variceal hemorrhage. Abdominal CT scan and endoscopy revealed large gastric varices. The patient underwent a TIPS procedure. Portal venography demonstrated persistent filling of the large gastric varices with associated high-flow spontaneous splenorenal shunt. Because of the large size of the varices, a Simon-Nitinol filter was used in conjunction with multiple embolization coils to enable successful occlusion of the varices.

  15. Lumbar epidural varices: An unusual cause of lumbar claudication

    PubMed Central

    Subbiah, Meenakshisundaram; Yegumuthu, Krishnan

    2016-01-01

    Lumbar epidural varices can also present with radiculopathy similar to acute intervertebral disc prolapse (IVDP). However as the magnetic resonance imaging (MRI) in these patients are usually normal without significant compressive lesions of the nerve roots, the diagnosis is commonly missed or delayed leading to persistent symptoms. We present a rare case of acute severe unilateral claudication with a normal MRI unresponsive to conservative management who was treated surgically. The nerve root on the symptomatic side was found to be compressed by large anterior epidural varices secondary to an abnormal cranial attachment of ligamentum flavum. Decompression of the root and coagulation of the varices resulted in complete pain relief. To conclude, lumbar epidural varices should be considered in the differential diagnosis of acute onset radiculopathy and claudication in the absence of significant MRI findings. PMID:27512228

  16. ENDOSCOPIC DIAGNOSIS AND THERAPY IN GASTRO-ESOPAGEAL VARICEAL BLEEDING

    PubMed Central

    Sanyal, Arun J.

    2016-01-01

    Gastroesophageal variceal hemorrhage is a medical emergency with high morbidity and mortality. Endoscopic therapy is the mainstay of management of bleeding varices. It requires attention to technique and the appropriate choice of therapy for a given patient at a given point in time. Subjects must be monitored continuously after initiation of therapy for control of bleeding and second line definitive therapies introduced quickly if endoscopic and pharmacologic treatment fails. PMID:26142034

  17. Bleeding from peristomal varices: perspectives on prevention and treatment.

    PubMed

    Fucini, C; Wolff, B G; Dozois, R R

    1991-12-01

    Peristomal variceal bleeding is a serious complication in patients with chronic liver disease undergoing colon surgery with a stoma. Our aim was to examine the morbidity of bleeding for peristomal, perianastomotic, and esophageal varices in a group of patients with chronic liver disease who underwent colectomy at the Mayo Clinic between 1970 and 1988. Morbidity was evaluated in terms of the number of major bleeding episodes and the number of units of blood transfused. The treatment of bleeding was also evaluated. One hundred seventeen patients (74 males and 43 females) aged 11-78 years were studied. Sixty-two patients (53 percent) had a permanent stoma, while 55 patients (47 percent) had a colonic resection and anastomosis. Sixty-seven patients (62 percent) had chronic ulcerative colitis and primary sclerosing cholangitis. In the stoma group, bleeding appeared from stomal and/or esophageal varices in 19 patients (31 percent), while, in the non-stoma group, bleeding exclusively from the esophageal varices occurred in eight patients (15 percent). Perianastomotic variceal bleeding was never observed. The 5-year cumulative probabilities of one major bleed occurring from gastrointestinal varices appeared to be similar between the two groups. Patients who bled from peristomal varices with or without esophageal bleeding (n = 17) rebled more frequently (6.5 +/- 5.5 vs. 3 +/- 1.6; P less than 0.05) and were transfused more often (14.9 +/- 12.3 vs. 7.5 +/- 4.1; P less than 0.05) than patients who bled exclusively from esophageal varices (n = 10). No difference was found in the incidence of recurrent bleeding and the number of units of blood transfused between patients who bled exclusively from peristomal varices (n = 10) and those who bled from both peristomal and esophageal varices (n = 7). Medical and local measures were more effective in controlling esophageal bleeding than in controlling peristomal bleeding. Therefore, patients with chronic liver disease who must undergo

  18. Combined Uphill and Downhill Varices as a Consequence of Rheumatic Heart Disease: A Unique Presentation

    PubMed Central

    Harwani, Yogesh P.; Kumar, Ajit; Chaudhary, Akash; Kumar, Manoj; Choudeswari, Padmavathi R.; Kankanala, Vishnu V.; Joshi, Nayana; Kansagra, Chintan; Shah, Sandip; Tripathi, Abhisheka

    2014-01-01

    Hemorrhage from downhill varices is a rare manifestation. The etiology of downhill varices is due to superior vena cava obstruction while uphill varices are secondary to portal hypertension. We report a rare case of 55-year-old female with bleeding downhill varices not associated with obstruction or compression of superior vena cava, but was due to severe pulmonary artery hypertension secondary to chronic rheumatic heart disease. PMID:25755536

  19. Validation of an Endoscopic Fibre-Optic Pressure Sensor for Noninvasive Measurement of Variceal Pressure

    PubMed Central

    Sun, Bin; Kong, De-Run; Li, Su-Wen; Yu, Dong-Feng; Wang, Ging-Jing; Yu, Fang-Fang; Wu, Qiong; Xu, Jian-Ming

    2016-01-01

    In this study, the authors have developed endoscopic fibre-optic pressure sensor to detect variceal pressure and presented the validation of in vivo and in vitro studies, because the HVPG requires catheterization of hepatic veins, which is invasive and inconvenient. Compared with HVPG, it is better to measure directly the variceal pressure without puncturing the varices in a noninvasive way. PMID:27314010

  20. Validation of an Endoscopic Fibre-Optic Pressure Sensor for Noninvasive Measurement of Variceal Pressure.

    PubMed

    Sun, Bin; Kong, De-Run; Li, Su-Wen; Yu, Dong-Feng; Wang, Ging-Jing; Yu, Fang-Fang; Wu, Qiong; Xu, Jian-Ming

    2016-01-01

    In this study, the authors have developed endoscopic fibre-optic pressure sensor to detect variceal pressure and presented the validation of in vivo and in vitro studies, because the HVPG requires catheterization of hepatic veins, which is invasive and inconvenient. Compared with HVPG, it is better to measure directly the variceal pressure without puncturing the varices in a noninvasive way. PMID:27314010

  1. Safety of direct endoscopic necrosectomy in patients with gastric varices

    PubMed Central

    Storm, Andrew C; Thompson, Christopher C

    2016-01-01

    AIM: To determine the feasibility and safety of transgastric direct endoscopic necrosectomy (DEN) in patients with walled-off necrosis (WON) and gastric varices. METHODS: A single center retrospective study of consecutive DEN for WON was performed from 2012 to 2015. All DEN cases with gastric fundal varices noted on endoscopy, computed tomography (CT) or magnetic resonance imaging (MRI) during the admission for DEN were collected for analysis. In all cases, external urethral sphincter (EUS) with doppler was used to exclude the presence of intervening gastric varices or other vascular structures prior to 19 gauge fine-needle aspiration (FNA) needle access into the cavity. The tract was serially dilated to 20 mm and was entered with an endoscope for DEN. Pigtail stents were placed to facilitate drainage of the cavity. Procedure details were recorded. Comprehensive chart review was performed to evaluate for complications and WON recurrence. RESULTS: Fifteen patients who underwent DEN for WON had gastric varices at the time of their procedure. All patients had an INR < 1.5 and platelets > 50. Of these patients, 11 had splenic vein thrombosis and 2 had portal vein thrombosis. Two patients had isolated gastric varices, type 1 and the remaining 13 had > 5 mm gastric submucosal varices on imaging by CT, MRI or EUS. No procedures were terminated without completing the DEN for any reason. One patient had self-limited intraprocedural bleeding related to balloon dilation of the tract. Two patients experienced delayed bleeding at 2 and 5 d post-op respectively. One required no therapy or intervention and the other received 1 unit transfusion and had an EGD which revealed no active bleeding. Resolution rate of WON was 100% (after up to 2 additional DEN in one patient) and no patients required interventional radiology or surgical interventions. CONCLUSION: In patients with WON and gastric varices, DEN using EUS and doppler guidance may be performed safely. Successful resolution

  2. Bleeding Duodenal: Varices Treatment by TIPS and Transcatheter Embolization

    SciTech Connect

    Lopera, Jorge E. Arthurs, Blain; Scheuerman, Christian; Sandoz, Charles; Petersosn, Scott; Castaneda-Zuniga, Wildriodo

    2008-03-15

    We describe our clinical experience in 4 patients with portal hypertension who presented with bleeding mesenteric varices originating from the superior mesenteric vein with retrograde filling of collaterals draining into the inferior vena cava. The clinical presentation, imaging findings, and potential therapeutic management are discussed.

  3. Circadian occurrence of variceal bleeding in patients with liver cirrhosis.

    PubMed

    Siringo, S; Bolondi, L; Sofia, S; Hermida, R C; Gramantieri, L; Gaiani, S; Piscaglia, F; Carbone, C; Misitano, B; Corinaldesi, R

    1996-12-01

    Several clinical events have a rhythmicity over the 24 h period. We assessed the presence of periodic rhythm in the occurrence of haematemesis in patients with liver cirrhosis under different daylight regimens, namely during standard time and during daylight savings. Over a 48 month period there were 212 consecutive admissions of 118 cirrhotics with variceal bleeding. Complete data were available for 181 episodes of bleeding: 121 (66.9%) started with haematemesis and 60 (33.1%) started with melaena. One hundred and two (56%) episodes occurred during daylight savings and 79 (44%) occurred during standard time. The cosinor test showed a 24 h biphasic peak for the occurrence of haematemesis (09.45 and 21.45 h). Moreover, a biphasic diurnal asymmetric frequency was also found by multiple component rhythmometry. The time peaks of onset of variceal haemorrhage did not change significantly during standard time and daylight savings. Patients with more than one haematemesis episode significantly bled over the same time interval. The present study confirms that over the 24 h period variceal bleeding in cirrhotic patients occurs with a predictable rhythmicity that does not seem to be under the control of the light-dark cycle. The finding of a chronorisk for variceal haemorrhage addresses specific questions for pathophysiological studies as well as for new treatment strategies.

  4. Prevention of Portal Hypertension: from Variceal Development to Clinical Decompensation

    PubMed Central

    Vorobioff, Julio D.; Groszmann, Roberto J

    2015-01-01

    Pharmacological treatment of portal hypertension (PH) has been exclusively devoted to gastro-esophageal varices related events at different frameworks including prophylactic, emergency or preventive therapy. The goals of treatment are to avoid the first bleeding episode, stop active bleeding and prevent bleeding recurrence, respectively. The objective of pre-primary prophylaxis (PPP) is to avoid variceal development and therefore, it necessarily deals with cirrhotic patients at earlier stages of the disease. At these earlier stages, nonselective beta blocker (NSBB) have been ineffective in preventing the development of varices and other complications of PH. Therefore, treatment should not rely on NSBB. It is possible, that at these earlier stages, etiological treatment of liver disease itself could prevent the progression of PH. This review will focus mainly on early treatment of PH, because if successful, it may translate into histological-hemodynamic improvements, avoiding not only variceal development but also other PH related complications, such as ascites and porto-systemic encephalopathy (PSE). Moreover, the advent of new therapies may allow not only the prevention of the complications of PH, but also the chance of a substantial degree of regression in the cirrhotic process with the possible prevention of hepatocellular carcinoma (HCC). PMID:24913395

  5. Vulvar varices: an uncommon entity in surgical pathology.

    PubMed

    Bell, Diana; Kane, Philip B; Liang, Sharon; Conway, Christine; Tornos, Carmen

    2007-01-01

    Varicose veins in the vulvar and perivulvar area are seen in 4% of women. Most of them are secondary to pregnancy and usually regress spontaneously. Vulvar varicose veins are rare in nonpregnant women. When present, they can be seen alone, associated with leg varices or associated with venous malformations of the labia, clitoral area, or vagina with or without arteriovenous malformations on the limbs or trunk (Klippel-Trenaunay-Weber syndrome and Parkes-Weber syndrome). In some cases, vulvar varices are seen as part of the so-called "pelvic congestion syndrome." Clinically, vulvar varices may present as small isolated protrusions, mainly in the labia majora, or as large masses, involving the vulva and even the perivulvar area. The treatment of choice of vulvar varices seen during pregnancy is conservative and symptomatic. Surgical pathologists need to be aware of the existence of vulvar varicose veins and its possible presence in biopsy specimens. Vulvar varicose veins can be misdiagnosed clinically as cysts or masses mainly in the Bartholin gland area. Correct diagnosis of the lesion is important to determine appropriate therapy and to recognize the possibility of associated anatomical or pathological problems.

  6. Case Report: Gallbladder Varices in a Patient with Portal Vein Thrombosis Secondary to Hepatocellular Carcinoma

    PubMed Central

    Gnerre, Jeffrey; Sun, Yankai; Jedynak, Andrzej; Gilet, Anthony

    2016-01-01

    Gallbladder varices are a rare form of collateralization that develop in patients with portal hypertension. We present here a case of gallbladder varices accurately diagnosed by contrast enhanced CT imaging of the abdomen and confirmed by Color Doppler Sonography. A 76-year-old patient with hepatocellular carcinoma developed portal vein thrombosis due to tumor extension during the course of treatment and was incidentally discovered to have gallbladder varices. While most commonly asymptomatic, gallbladder varices are associated with increased risk of massive bleeding, either spontaneously or during cholecystectomy. As a result, the existence of such varices should be well documented if the patient is to undergo any abdominal surgical procedures. In addition, because of a particular association with portal vein thrombosis, patients with portal hypertension that are found to possess gallbladder varices should be evaluated for portal vein thrombosis. PMID:27761177

  7. Balloon-Occluded Retrograde Transvenous Obliteration for Gastric Varices: A Feasibility Study

    SciTech Connect

    Sonomura, Tetsuo; Sato, Morio; Kishi, Kazushi; Terada, Masaki; Shioyama, Yasukazu; Kimura, Masashi; Suzuki, Kenzo; Kutsukake, Yasumichi; Ushimi, Takashi; Tanaka, Junji; Hayashi, Seishu; Tanaka, Satoshi

    1998-01-15

    Purpose: To evaluate the clinical feasibility of balloon-occluded retrograde transvenous obliteration (BORTO) for gastric varices. Methods: BORTO was performed in 14 patients with gastric varices due to liver cirrhosis. The gastric varices were confirmed by endoscopy, and their feeding and draining veins were identified by contrast-enhanced computed tomography (CT) and angiography. A 6 Fr Simmons-shaped balloon catheter was inserted into the gastrorenal shunt. The balloon was inflated, and 5% ethanolamine oleate iopamidol was infused slowly through the catheter. Patients were followed up with endoscopy and enhanced CT at 1 week, 1, 3, and 6 months after the procedure and every 6 months thereafter. Results: The gastric varices completely disappeared in 12 of 14 patients and was partially resolved in the remaining 2 patients. Neither a recurrence nor an aggravation of gastric varices were found. No major complications were experienced. Conclusion: BORTO is a safe and effective treatment for gastric varices.

  8. Bleeding due to ectopic varices in a urinary diversion: A multidisciplinary diagnostic and therapeutic challenge

    PubMed Central

    Acosta, Eduardo Mariano Albers; Reyes, Alfonsi Friera; Menéndez, Ricardo Brime

    2015-01-01

    The ectopic varices in patients with portal hypertension are those that occur at any level of the gastrointestinal (GI) tract, regardless of the varices that occur at the esophageal level. These ectopic varices account for 2–5% of the causes of GI bleeding varices. The risk of bleeding is quadrupled compared to the esophagogastric area, with a mortality of up to 40%. The transjugular intrahepatic portosystemic shunt, should be considered in cases secondary to recurrent bleeding varices. We present a case report of an urological emergency of bleeding in a urinary diversion secondary to ectopic varices successfully treated through the placement of transjugular intrahepatic portosystemic shunt. The condition described here is rare, but important, as it can be a life-threatening complication of portal hypertension. This kind of complication should be known by urologic surgeons managing patients with urinary diversions. PMID:26834901

  9. [Latex ligation in treatment of chronic hemorrhoids].

    PubMed

    Ektov, V N; Somov, K A

    2015-01-01

    We analyzed the results of treatment of 432 patients with chronic hemorrhoids using different variants of latex ligation. New technique including ligation of mucosa and submucosa of low-ampullar rectum providing ligation of hemorrhoidalvessels, lifting and recto-anal repair is developed and suggested. This method is advisable to use in case of chronic internal hemorrhoids stages I and II. The authors recommend simultaneous combined ligation of mucosa of low-ampullar rectum and internal hemorrhoids for stages III and IV. Different variants of latex ligation with external hemorrhoids excision were used in 103 patients. Pointed variants of latex ligation preserve important advantages including mini-invasiveness, simplicity and wide availability, low cost. Good remote results were obtained after these procedures in 87.3% of observations. Suggested tactics extends use of latex ligation and increases its effectiveness in treatment of different stages and forms of chronic hemorrhoids.

  10. Staudinger ligation as a method for bioconjugation.

    PubMed

    van Berkel, Sander S; van Eldijk, Mark B; van Hest, Jan C M

    2011-09-12

    In 1919 the German chemist Hermann Staudinger was the first to describe the reaction between an azide and a phosphine. It was not until recently, however, that Bertozzi and co-workers recognized the potential of this reaction as a method for bioconjugation and transformed it into the so-called Staudinger ligation. The bio-orthogonal character of both the azide and the phosphine functions has resulted in the Staudinger ligation finding numerous applications in various complex biological systems. For example, the Staudinger ligation has been utilized to label glycans, lipids, DNA, and proteins. Moreover, the Staudinger ligation has been used as a synthetic method to construct glycopeptides, microarrays, and functional biopolymers. In the emerging field of bio-orthogonal ligation strategies, the Staudinger ligation has set a high standard to which most of the new techniques are often compared. This Review summarizes recent developments and new applications of the Staudinger ligation.

  11. Septic Complication After Balloon-Occluded Retrograde Transvenous Obliteration of Duodenal Variceal Bleeding

    SciTech Connect

    Akasaka, Thai; Shibata, Toshiya Isoda, Hiroyoshi; Taura, Kojiro; Arizono, Shigeki; Shimada, Kotaro; Togashi, Kaori

    2010-12-15

    We report a 64-year-old woman with duodenal varices who underwent balloon-occluded retrograde transvenous obliteration (B-RTO) complicated by intraprocedural variceal rupture. The patient developed shivering and a fever higher than 40{sup o}C 3 days after the B-RTO procedure. A blood culture grew Entereobacter cloacoe. This case represents a rare septic complication of B-RTO for duodenal varices.

  12. Percutaneous Retrograde Sclerotherapy for Refractory Bleeding of Jejunal Varices: Direct Injection via Superficial Epigastric Vein

    SciTech Connect

    Nakata, Manabu Nakata, Waka; Isoda, Norio Yoshizawa, Mitsuyo; Sugimoto, Hideharu

    2012-02-15

    Small-bowel varices are rare and almost always occur in cases with portal hypertension. We encountered a patient with bleeding jejunal varices due to liver cirrhosis. Percutaneous retrograde sclerotherapy was performed via the superficial epigastric vein. Melena disappeared immediately after treatment. Disappearance of jejunal varices was confirmed by contrast-enhanced computed tomography. After 24 months of follow-up, no recurrent melena was observed.

  13. Oesophageal and gastric varices: historical aspects, classification and grading: everything in one place

    PubMed Central

    Abby Philips, Cyriac; Sahney, Amrish

    2016-01-01

    Variceal disease and its management are of the utmost importance in the treatment of portal hypertension. Current guidelines are universal for management of variceal disease in portal hypertension. Classification and grading systems are numerous and differ according to geographical location. In this exhaustive review, the historical aspects of variceal disease, its classification and the grading systems in use are discussed, with self-explanatory tables and timelines. A better and clear understanding of the evolution of portal hypertension and variceal disease is provided. PMID:27324725

  14. Bleeding esophageal varices: treatment with vasopressin, transhepatic embolization and selective splenorenal shunting.

    PubMed Central

    Johnson, W C; Nabseth, D C; Widrich, W C; Bush, H L; O'Hara, E T; Robbins, A H

    1982-01-01

    The fate of 359 consecutive alcoholic cirrhotic male patients with bleeding esophageal varices was determined through chart review and personal interview. Three historical periods (1966-70; 1971-75; 1976-80) were defined based on availability of different therapeutic modalities. Management of acutely bleeding varices by conservative, nonsurgical means, including embolization, was preferable to emergency surgery when considering 30-day mortality rates. Percutaneous transhepatic embolization of esophagogastric varices significantly improved the rate of control of hemorrhage and 30-day survival over previously employed nonsurgical methods. The combination of nonsurgical management of acute variceal hemorrhage followed by selective distal splenorenal shunting resulted in maximum salvage of the alcoholic cirrhotic patient. PMID:6978109

  15. No difference in mortality between terlipressin and somatostatin treatments in cirrhotic patients with esophageal variceal bleeding and renal functional impairment

    PubMed Central

    Hung, Tsung-Hsing; Tsai, Chen-Chi; Tseng, Kuo-Chih; Hsieh, Yu-Hsi; Tsai, Chih-Chun

    2016-01-01

    Objective To study the differences in mortality between terlipressin and somatostatin treatments in cirrhotic patients with esophageal variceal bleeding (EVB) and renal functional impairment (RFI). Methods The National Health Insurance Database, part of the Taiwan National Health Insurance Program, was used to enroll cirrhotic patients who had received endoscopic variceal ligation plus somatostatin or terlipressin for EVB and who were hospitalized between 1 January 2007 and 31 December 2010. The differences in mortality between the two vasoactive agents were compared and the risk factors for 30-day mortality because of EVB were identified. Results A total of 2324 cirrhotic patients with EVB were enrolled. The 30-day mortality data showed no significant differences between the somatostatin and the terlipressin groups (P=0.232). The risk of 30-day mortality was significantly higher in male patients [hazard ratio (HR): 1.50, P=0.002] and patients with hepatic encephalopathy (HR: 1.82, P<0.001), ascites (HR: 1.32, P=0.008), bacterial infections (HR: 2.10, P<0.001), hepatocellular carcinoma (HR: 2.09, P<0.001), and RFI (HR: 3.89, P<0.001). A subgroup analysis of cirrhotic patients with RFI was carried out. The overall 30-day mortality was higher in patients treated with somatostatin than in those treated with terlipressin (52.6 vs. 42.3%), but the difference failed to reach significance (adjust HR: 1.49, 95% confidence interval: 0.94–2.37, P=0.091). Conclusion RFI was the most important risk factor for 30-day mortality in EVB patients. Terlipressin and somatostatin had similar effects on 30-day mortality in cirrhotic patients with EVB and RFI. PMID:27455080

  16. Alternative Treatment for Bleeding Peristomal Varices: Percutaneous Parastomal Embolization

    SciTech Connect

    Pabon-Ramos, Waleska M.; Niemeyer, Matthew M.; Dasika, Narasimham L.

    2013-10-15

    Purpose: To describe how peristomal varices can be successfully embolized via a percutaneous parastomal approach. Methods: The medical records of patients who underwent this procedure between December 1, 2000, and May 31, 2008, were retrospectively reviewed. Procedural details were recorded. Median fluoroscopy time and bleeding-free interval were calculated. Results: Seven patients underwent eight parastomal embolizations. The technical success rate was 88 % (one failure). All embolizations were performed with coils combined with a sclerosant, another embolizing agent, or both. Of the seven successful parastomal embolizations, there were three cases of recurrent bleeding; the median time to rebleeding was 45 days (range 26-313 days). The remaining four patients did not develop recurrent bleeding during the follow-up period; their median bleeding-free interval was 131 days (range 40-659 days). Conclusion: This case review demonstrated that percutaneous parastomal embolization is a feasible technique to treat bleeding peristomal varices.

  17. Gluing Gastric Varices in 2012: Lessons Learnt Over 25 Years

    PubMed Central

    Saraswat, Vivek A; Verma, Abhai

    2012-01-01

    Bleeding from gastric varices (GV) continues to pose a challenge to the endoscopist and no consensus has been reached on the best way for treating these patients. Gastric variceal obturation (GVO) with the tissue adhesive, N-2-butyl-cyanoacrylate (NBC), is considered the treatment of first-choice for this condition in most parts of the world. The liquid monomer polymerizes into a solid cast, obturating the vessel within 10–20 s of coming in contact with ionic solutions such as blood. Gastric variceal obturation achieves hemostasis in over 90% of patients with active bleeding, eradicates GV in over 80% of these patients, and re-bleeding occurs in 3–30%. These results are comparable with those of transjugular intrahepatic portosystemic shunting (TIPS; over 90% hemostasis in acute bleeding with re-bleeding in 15–30%). Though, there has been no direct comparison with GVO, balloon-occluded retrograde transvenous obliteration of GV (BRTO) achieves near 100% obliteration with recurrence in 0–10% and is superior to TIPS for hemostasis in active bleeding when used in combination with transcatheter sclerotherapy. Several complications have been described for GVO including thromboembolic complications which occur in 0.5–4.3% and may be devastating in some. Many of the complications and the variability in results of GVO can be attributed to variations in injection technique. The use of a standardized injection technique has been reported to achieve 100% hemostasis and obliteration with 6.9% re-bleeding and no embolic complications. Gastric variceal obturation with NBC continues to be the first-choice therapy for GV bleeding outside Japan. Adherence to a standard injection technique will maximize hemostasis and eradication of GV while minimizing complications of therapy. PMID:25755406

  18. Transcatheter Embolotherapy with N-Butyl Cyanoacrylate for Ectopic Varices

    SciTech Connect

    Choi, Jin Woo; Kim, Hyo-Cheol Jae, Hwan Jun Jung, Hyun-Seok; Hur, Saebeom; Lee, Myungsu; Chung, Jin Wook

    2015-04-15

    PurposeTo address technical feasibility and clinical outcome of transcatheter embolotherapy with N-butyl cyanoacrylate (NBCA) for bleeding ectopic varices.MethodsThe institutional review board approved this retrospective study and waived informed consent. From January 2004 to June 2013, a total of 12 consecutive patients received transcatheter embolotherapy using NBCA for bleeding ectopic varices in our institute. Clinical and radiologic features of the endovascular procedures were comprehensively reviewed.ResultsPreprocedural computed tomography images revealed ectopic varices in the jejunum (n = 7), stoma (n = 2), rectum (n = 2), and duodenum (n = 1). The 12 procedures consisted of solitary embolotherapy (n = 8) and embolotherapy with portal decompression (main portal vein stenting in 3, transjugular intrahepatic portosystemic shunt in 1). With regard to vascular access, percutaneous transhepatic access (n = 7), transsplenic access (n = 4), and transjugular intrahepatic portosystemic shunt tract (n = 1) were used. There was no failure in either the embolotherapy or the vascular accesses (technical success rate, 100 %). Two patients died within 1 month from the procedure from preexisting fatal medical conditions. Only one patient, with a large varix that had been partially embolized by using coils and NBCA, underwent rebleeding 5.5 months after the procedure. The patient was retreated with NBCA and did not undergo any bleeding afterward for a follow-up period of 2.5 months. The remaining nine patients did not experience rebleeding during the follow-up periods (range 1.5–33.2 months).ConclusionTranscatheter embolotherapy using NBCA can be a useful option for bleeding ectopic varices.

  19. [Esophageal carcinoma after the endoscopic sclerotherapy of varices].

    PubMed

    Macías Rodríguez, M A; Soria de la Cruz, M J; Iglesias Arrabal, M; Martín Herrera, L

    1992-07-01

    We report the case of a 52-years-old smoking male, diagnosed of liver cirrhosis, who developed a squamous cell carcinoma of the esophagus 36 months after undergoing endoscopic injection sclerotherapy for bleeding esophageal varices. Nine courses with 3% polidocanol were performed along 10 months. It was injected intra and paravariceal at a total dose of 117 ml. The relationship between endoscopic injection sclerotherapy and developing squamous cell carcinoma of the esophagus is discussed.

  20. Symptomatic lumbar epidural varices. Report of two cases.

    PubMed

    Zimmerman, G A; Weingarten, K; Lavyne, M H

    1994-05-01

    Lumbar epidural varices have been infrequently described in the literature and rarely accepted as a primary pathophysiological entity. The authors' total experience with symptomatic lumbar epidural varices over the last 15 years includes four cases (incidence 0.067% of all lumbar spine operations), two of which are described in detail in this paper. The mechanism for their formation is proposed: central disc herniations obstruct the anterior epidural venous flow leading to anterolateral caudal venous distention. Subsequent venous endothelial injury predisposes to varying degrees of phlebothrombosis. Decompression of partially thrombosed varices may occur during operative discectomy or spontaneously during regression of the nonoperated disc prolapse. Regression of the central disc herniation may also explain the "disappearing disc" phenomenon, in which patients with clinical and radiographic evidence of apparently large caudal disc herniations exhibit clinical and radiographic resolution. Magnetic resonance (MR) imaging characteristics of the epidural varix depend upon the degree of thrombosis within this anomaly. A thrombosed varix is hyperintense on T1-weighted, proton-density, and T2-weighted images, whereas flowing blood is hypointense. The variable hypo- and hyperintensity on the T2-weighted MR imaging sequences correlate with a partially patent lumen within the varix. PMID:8169634

  1. Successful Treatment of Mesenteric Varices After Living Donor Liver Transplantation with Retrograde Transvenous Obliteration Via an Abdominal Wall Vein

    SciTech Connect

    Ikeda, Osamu Tamura, Yoshitaka; Nakasone, Yutaka; Yamashita, Yasuyuki; Okajima, Hideaki; Asonuma, Katsuhiro; Inomata, Yukihiro

    2010-06-15

    Balloon-occluded retrograde transvenous obliteration is an established treatment for gastric varices; it has been used more rarely to treat mesenteric varices. We report a 12-year-old girl who had received a living donor liver transplant and suffered melena due to ruptured mesenteric varices. We addressed treatment of the mesenteric varices by retrograde transvenous obliteration of an abdominal wall collateral vein detected by superior mesenteric arteriography.

  2. Acute management and secondary prophylaxis of esophageal variceal bleeding: A western Canadian survey

    PubMed Central

    Cheung, Justin; Wong, Winnie; Zandieh, Iman; Leung, Yvette; Lee, Samuel S; Ramji, Alnoor; Yoshida, Eric M

    2006-01-01

    BACKGROUND: Acute esophageal variceal bleeding (EVB) is a major cause of morbidity and mortality in patients with liver cirrhosis. Guidelines have been published in 1997; however, variability in the acute management and prevention of EVB rebleeding may occur. METHODS: Gastroenterologists in the provinces of British Columbia, Alberta, Manitoba and Saskatchewan were sent a self-reporting questionnaire. RESULTS: The response rate was 70.4% (86 of 122). Intravenous octreotide was recommended by 93% for EVB patients but the duration was variable. The preferred timing for endoscopy in suspected acute EVB was within 12 h in 75.6% of respondents and within 24 h in 24.6% of respondents. Most (52.3%) gastroenterologists do not routinely use antibiotic prophylaxis in acute EVB patients. The preferred duration of antibiotic therapy was less than three days (35.7%), three to seven days (44.6%), seven to 10 days (10.7%) and throughout hospitalization (8.9%). Methods of secondary prophylaxis included repeat endoscopic therapy (93%) and beta-blocker therapy (84.9%). Most gastroenterologists (80.2%) routinely attempted to titrate beta-blockers to a heart rate of 55 beats/min or a 25% reduction from baseline. The most common form of secondary prophylaxis was a combination of endoscopic and pharmacological therapy (70.9%). CONCLUSIONS: Variability exists in some areas of EVB treatment, especially in areas for which evidence was lacking at the time of the last guideline publication. Gastroenterologists varied in the use of prophylactic antibiotics for acute EVB. More gastroenterologists used combination secondary prophylaxis in the form of band ligation eradication and beta-blocker therapy rather than either treatment alone. Future guidelines may be needed to address these practice differences. PMID:16955150

  3. UK guidelines on the management of variceal haemorrhage in cirrhotic patients

    PubMed Central

    Tripathi, Dhiraj; Stanley, Adrian J; Hayes, Peter C; Patch, David; Millson, Charles; Mehrzad, Homoyon; Austin, Andrew; Ferguson, James W; Olliff, Simon P; Hudson, Mark; Christie, John M

    2015-01-01

    These updated guidelines on the management of variceal haemorrhage have been commissioned by the Clinical Services and Standards Committee (CSSC) of the British Society of Gastroenterology (BSG) under the auspices of the liver section of the BSG. The original guidelines which this document supersedes were written in 2000 and have undergone extensive revision by 13 members of the Guidelines Development Group (GDG). The GDG comprises elected members of the BSG liver section, representation from British Association for the Study of the Liver (BASL) and Liver QuEST, a nursing representative and a patient representative. The quality of evidence and grading of recommendations was appraised using the AGREE II tool. The nature of variceal haemorrhage in cirrhotic patients with its complex range of complications makes rigid guidelines inappropriate. These guidelines deal specifically with the management of varices in patients with cirrhosis under the following subheadings: (1) primary prophylaxis; (2) acute variceal haemorrhage; (3) secondary prophylaxis of variceal haemorrhage; and (4) gastric varices. They are not designed to deal with (1) the management of the underlying liver disease; (2) the management of variceal haemorrhage in children; or (3) variceal haemorrhage from other aetiological conditions. PMID:25887380

  4. Comparison of different methods for endoscopic hemostasis of bleeding canine esophageal varices.

    PubMed

    Jensen, D M; Silpa, M L; Tapia, J I; Beilin, D B; Machicado, G A

    1983-06-01

    Despite advances in the therapy of acute esophageal variceal hemorrhage, morbidity and mortality remain high. Continued severe variceal hemorrhage remains a major clinical problem in poor risk patients who cannot tolerate emergency surgery for hemostasis. Several endoscopic hemostatic methods might be effective for variceal hemostasis, but they have not been systematically evaluated. Using a reproducible canine model of esophageal varices, several hemostatic modalities were tested and compared to determine which were most effective in stopping variceal bleeding. Methods tested were endoscopic sclerotherapy, organ laser, neodymium-yttrium-aluminum-garnet laser, monopolar electro-coagulation, bipolar electrocoagulation, ferromagnetic tamponade, and endoscopic heater probe. Both neodymium-yttrium-aluminum-garnet laser and endoscopic sclerotherapy provided reliable hemostasis in acutely bleeding canine varices. Large heater probe controlled bleeding 50% of the time, and all the other methods stopped bleeding in less than half the trials. Rebleeding after balloon inflation proximal to the coagulated bleeding site did not occur with neodymium-yttrium-aluminum-garnet laser or endoscopic sclerotherapy-treated varices but did occur with the other methods. The principal differences between neodymium-yttrium-aluminum-garnet laser and endoscopic sclerotherapy were the ease of application of neodymium-yttrium-aluminum-garnet laser, the higher frequency of esophageal ulcers or erosions with neodymium-yttrium-aluminum-garnet laser, and the lack of variceal obliteration with neodymium-yttrium-aluminum-garnet laser. PMID:6341157

  5. Bleeding oesophageal varices associated with anabolic steroid use in an athlete.

    PubMed Central

    Winwood, P. J.; Robertson, D. A.; Wright, R.

    1990-01-01

    A 30 year old bodybuilder who had been taking anabolic steroids for 18 months presented with bleeding oesophageal varices. Serious liver disease secondary to anabolic steroids including peliosis hepatis, nodular hyperplasia and malignant change is well recognized. We report what is, to our knowledge, the first case of bleeding oesophageal varices associated with the use of anabolic steroids. PMID:2099434

  6. Comparison of different methods for endoscopic hemostasis of bleeding canine esophageal varices.

    PubMed

    Jensen, D M; Silpa, M L; Tapia, J I; Beilin, D B; Machicado, G A

    1983-06-01

    Despite advances in the therapy of acute esophageal variceal hemorrhage, morbidity and mortality remain high. Continued severe variceal hemorrhage remains a major clinical problem in poor risk patients who cannot tolerate emergency surgery for hemostasis. Several endoscopic hemostatic methods might be effective for variceal hemostasis, but they have not been systematically evaluated. Using a reproducible canine model of esophageal varices, several hemostatic modalities were tested and compared to determine which were most effective in stopping variceal bleeding. Methods tested were endoscopic sclerotherapy, organ laser, neodymium-yttrium-aluminum-garnet laser, monopolar electro-coagulation, bipolar electrocoagulation, ferromagnetic tamponade, and endoscopic heater probe. Both neodymium-yttrium-aluminum-garnet laser and endoscopic sclerotherapy provided reliable hemostasis in acutely bleeding canine varices. Large heater probe controlled bleeding 50% of the time, and all the other methods stopped bleeding in less than half the trials. Rebleeding after balloon inflation proximal to the coagulated bleeding site did not occur with neodymium-yttrium-aluminum-garnet laser or endoscopic sclerotherapy-treated varices but did occur with the other methods. The principal differences between neodymium-yttrium-aluminum-garnet laser and endoscopic sclerotherapy were the ease of application of neodymium-yttrium-aluminum-garnet laser, the higher frequency of esophageal ulcers or erosions with neodymium-yttrium-aluminum-garnet laser, and the lack of variceal obliteration with neodymium-yttrium-aluminum-garnet laser.

  7. Massive duodenal variceal bleed; complication of extra hepatic portal hypertension: Endoscopic management and literature review

    PubMed Central

    Steevens, Christopher; Abdalla, Maisa; Kothari, Truptesh H; Kaul, Vivek; Kothari, Shivangi

    2015-01-01

    Bleeding from duodenal varices is reported to be a catastrophic and often fatal event. Most of the cases in the literature involve patients with underlying cirrhosis. However, approximately one quarter of duodenal variceal bleeds is caused by extrahepatic portal hypertension and they represent a unique population given their lack of liver dysfunction. The authors present a case where a 61-year-old male with history of remote crush injury presented with bright red blood per rectum and was found to have bleeding from massive duodenal varices. Injection sclerotherapy with ethanolamine was performed and the patient experienced a favorable outcome with near resolution of his varices on endoscopic follow-up. The authors conclude that sclerotherapy is a reasonable first line therapy and review the literature surrounding the treatment of duodenal varices secondary to extrahepatic portal hypertension. PMID:26558159

  8. Percutaneous Trans-hepatic Obliteration for Bleeding Esophagojejunal Varices After Total Gastrectomy and Esophagojejunostomy

    SciTech Connect

    Boku, Michiko; Sugimoto, Koji; Nakamura, Tetsu; Kita, Yasufumi; Zamora, Carlos A. Sugimura, Kazuro

    2006-12-15

    A 72-year-old man who had undergone a total gastrectomy with a Roux-en-Y esophagojejunostomy for gastric cancer 6 years earlier presented to our hospital with massive hematemesis and melena. Endoscopic examination indicated esophageal varices with cherry-red spots and hemorrhage arising from beyond the anastomosis. Abdominal contrast-enhanced computed tomography and angiography revealed a dilated vein in the elevated jejunal limb supplying the varices. Percutaneous trans-hepatic obliteration (PTO) of the varices through the jejunal vein was performed using microcoils, ethanolamine oleate, and gelatin sponge cubes. Ten days after the procedure, endoscopic examination revealed reduction and thrombosis of the varices. We consider PTO to be an effective alternative method for treating ruptured esophagojejunal varices after total gastrectomy.

  9. The "Floss-Ligature" Ligation Technique.

    PubMed

    Dugdale, Charlotte Anne; Malik, Ovais Humair; Waring, David Trevor

    2015-01-01

    This clinical pearl describes an alternative technique to aid effective ligation of rotated teeth during the aligning stage of fixed appliance treatment. This technique has the potential to improve patient experience and confidence, by reducing the risk of trauma and discomfort and treatment efficiency, by ensuring complete ligation of even severely rotated teeth.

  10. 21 CFR 876.4400 - Hemorrhoidal ligator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Hemorrhoidal ligator. 876.4400 Section 876.4400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4400 Hemorrhoidal ligator....

  11. 21 CFR 876.4400 - Hemorrhoidal ligator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Hemorrhoidal ligator. 876.4400 Section 876.4400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4400 Hemorrhoidal ligator....

  12. 21 CFR 876.4400 - Hemorrhoidal ligator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Hemorrhoidal ligator. 876.4400 Section 876.4400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4400 Hemorrhoidal ligator....

  13. 21 CFR 876.4400 - Hemorrhoidal ligator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Hemorrhoidal ligator. 876.4400 Section 876.4400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4400 Hemorrhoidal ligator....

  14. 21 CFR 876.4400 - Hemorrhoidal ligator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hemorrhoidal ligator. 876.4400 Section 876.4400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4400 Hemorrhoidal ligator....

  15. Left renal vein ligation: a technique to mitigate low portal flow from splenic vein siphon during liver transplantation.

    PubMed

    Slater, R R; Jabbour, N; Abbass, A Abou; Patil, V; Hundley, J; Kazimi, M; Kim, D; Yoshida, A; Abouljoud, M

    2011-08-01

    Low portal vein flows in liver transplant have been associated with poor allograft survival. Identifying and ameliorating causes of inadequate portal flow is paramount. We describe successful reversal of significant splenic vein siphon from a spontaneous splenorenal shunt during liver transplant. The patient is a 43-year-old male with cirrhosis from hepatitis C and Budd-Chiari syndrome, who had a variceal hemorrhage necessitating an emergent splenorenal shunt with 8 mm PTFE graft. Imaging in 2006 revealed thrombosis of the splenorenal shunt and evidence of a new spontaneous splenorenal shunt. The patient developed hepatocellular carcinoma and underwent transplant in 2009. After reperfusion, portal flows were low (150-200 mL/min). A mesenteric varix was ligated without improvement. Due to adhesions, direct collateral ligation was not attempted. In order to redirect the splenic siphon, the left renal vein was stapled at its confluence with the inferior vena cava. Portal flows subsequently increased to 1.28 L/min. Postoperatively, the patient had stable renal and liver function. We conclude that spontaneous splenorenal shunts can cause low portal flows. A diligent search for shunts with understanding of flow patterns is critical; ligation or rerouting of splanchnic flow may be necessary to improve portal flows and allograft outcomes.

  16. Medical expenses in treating acute esophageal variceal bleeding

    PubMed Central

    Liu, Chueh-Ling; Wu, Cheng-Kun; Shi, Hon-Yi; Tai, Wei-Chen; Liang, Chih-Ming; Yang, Shih-Cheng; Wu, Keng-Liang; Chiu, Yi-Chun; Chuah, Seng-Kee

    2016-01-01

    Abstract Acute variceal bleeding in patients with cirrhosis is related to high mortality and medical expenses. The purpose of present studies was to analyze the medical expenses in treating acute esophageal variceal bleeding among patients with cirrhosis and potential influencing clinical factors. A total of 151,863 patients with cirrhosis with International Classification of Diseases-9 codes 456.0 and 456.20 were analyzed from the Taiwan National Health Insurance Research Database from January 1, 1996 to December 31, 2010. Time intervals were divided into three phases for analysis as T1 (1996–2000), T2 (2001–2005), and T3 (2006–2010). The endpoints were prevalence, length of hospital stay, medical expenses, and mortality rate. Our results showed that more patients were <65 years (75.6%) and of male sex (78.5%). Patients were mostly from teaching hospitals (90.8%) with high hospital volume (50.9%) and high doctor service load (51.1%). The prevalence of acute esophageal variceal bleeding and mean length of hospital stay decreased over the years (P < 0.001), but the overall medical expenses increased (P < 0.001). Multiple regression analysis showed that older age, female sex, Charlson comorbidity index (CCI) score >1, patients from teaching hospitals, and medium to high or very high patient numbers were independent factors for longer hospital stay and higher medical expenses. Aged patients, female sex, increased CCI score, and low doctor service volume were independent factors for both in-hospital and 5-year mortality. Patients from teaching hospitals and medium to high or very high service volume hospitals were independent factors for in-hospital mortality, but not 5-year mortality. Medical expenses in treating acute esophageal variceal bleeding increased despite the decreased prevalence rate and length of hospital stay in Taiwan. Aged patients, female sex, patients with increased CCI score from teaching hospitals, and medium to high or very high

  17. Acute bleeding varices: a five-year prospective evaluation of tamponade and sclerotherapy.

    PubMed Central

    Terblanche, J; Yakoob, H I; Bornman, P C; Stiegmann, G V; Bane, R; Jonker, M; Wright, J; Kirsch, R

    1981-01-01

    In a five-year study of massive upper gastrointestinal hemorrhage, 143 patients had esophageal varices diagnosed on emergency endoscopic examination. Seventy-one patients had active bleeding from varices and required Sengstaken tube tamponade during at least one hospital admission. The remaining patients included 33 with variceal bleeding which had stopped and 39 who were bleeding from another source. Sixty-six of the former group of 71 patients were referred for emergency injection sclerotherapy. These 66 patients were followed prospectively to August 1980, and had 137 episodes of endoscopically proven variceal bleeding requiring Sengstaken tube control followed by injection sclerotherapy during 93 separate hospital admissions. Definitive control of hemorrhage was achieved in 95% the patients admitted to the hospital (single injection 70%; two or three injections 22%). The death rate per hospital admission was 28%. No patient died of continued variceal bleeding, and exsanguinating variceal hemorrhage no longer poses a major problem at our hospital. The combined use of initial Sengstaken tube tamponade followed by injection sclerotherapy has simplified emergency treatment in the group of patients who continue to bleed actively from esophageal varices, despite initial conservative treatment. Images Fig. 1. PMID:7025770

  18. Kinetics of ligation of fibrin oligomers.

    PubMed

    Nelb, G W; Kamykowski, G W; Ferry, J D

    1980-07-10

    Human fibrinogen was treated with thrombin in the presence of fibrinoligase and calcium ion at pH 8.5, ionic strength 0.45, and the ensuring polymerization was interrupted at various time intervals (t) both before and after the clotting time (tc) by solubilization with a solution of sodium dodecyl sulfate and urea. Aliquots of the solubilized protein were subjected to gel electrophoresis on polyacrylamide gels after disulfide reduction by dithiothreitol and on agarose gels without reduction. The degree of gamma-gamma ligation was determined from the former and the size distribution of ligated oligomers, for degree of polymerization x from 1 to 10, from the latter. The degree of gamma-gamma ligation was calculated independently from the size distribution with the assumption that every junction between two fibrin monomers remaining intact after solubilization is ligated, and this agreed well with the direct determination. The size distribution at t/tc = 1.3 to 1.6 differed somewhat from that calculated by the classical theory of linear polycondensation on the assumption that all reactive sites react with equal probability and rate. Analysis of the difference suggests that ligation of a fibrin digomer is not a random process; the probability of ligation of a given junction between two monomers increases with the oligomer length. The number-average degree of polymerization, xn, of ligated oligomers increases approximately linearly with time up to a value of 1.6. PMID:7391026

  19. Diagnosis and therapy of non-variceal upper gastrointestinal bleeding

    PubMed Central

    Biecker, Erwin

    2015-01-01

    Non-variceal upper gastrointestinal bleeding (UGIB) is defined as bleeding proximal to the ligament of Treitz in the absence of oesophageal, gastric or duodenal varices. The clinical presentation varies according to the intensity of bleeding from occult bleeding to melena or haematemesis and haemorrhagic shock. Causes of UGIB are peptic ulcers, Mallory-Weiss lesions, erosive gastritis, reflux oesophagitis, Dieulafoy lesions or angiodysplasia. After admission to the hospital a structured approach to the patient with acute UGIB that includes haemodynamic resuscitation and stabilization as well as pre-endoscopic risk stratification has to be done. Endoscopy offers not only the localisation of the bleeding site but also a variety of therapeutic measures like injection therapy, thermocoagulation or endoclips. Endoscopic therapy is facilitated by acid suppression with proton pump inhibitor (PPI) therapy. These drugs are highly effective but the best route of application (oral vs intravenous) and the adequate dosage are still subjects of discussion. Patients with ulcer disease are tested for Helicobacter pylori and eradication therapy should be given if it is present. Non-steroidal anti-inflammatory drugs have to be discontinued if possible. If discontinuation is not possible, cyclooxygenase-2 inhibitors in combination with PPI have the lowest bleeding risk but the incidence of cardiovascular events is increased. PMID:26558151

  20. Diagnosis and therapy of non-variceal upper gastrointestinal bleeding.

    PubMed

    Biecker, Erwin

    2015-11-01

    Non-variceal upper gastrointestinal bleeding (UGIB) is defined as bleeding proximal to the ligament of Treitz in the absence of oesophageal, gastric or duodenal varices. The clinical presentation varies according to the intensity of bleeding from occult bleeding to melena or haematemesis and haemorrhagic shock. Causes of UGIB are peptic ulcers, Mallory-Weiss lesions, erosive gastritis, reflux oesophagitis, Dieulafoy lesions or angiodysplasia. After admission to the hospital a structured approach to the patient with acute UGIB that includes haemodynamic resuscitation and stabilization as well as pre-endoscopic risk stratification has to be done. Endoscopy offers not only the localisation of the bleeding site but also a variety of therapeutic measures like injection therapy, thermocoagulation or endoclips. Endoscopic therapy is facilitated by acid suppression with proton pump inhibitor (PPI) therapy. These drugs are highly effective but the best route of application (oral vs intravenous) and the adequate dosage are still subjects of discussion. Patients with ulcer disease are tested for Helicobacter pylori and eradication therapy should be given if it is present. Non-steroidal anti-inflammatory drugs have to be discontinued if possible. If discontinuation is not possible, cyclooxygenase-2 inhibitors in combination with PPI have the lowest bleeding risk but the incidence of cardiovascular events is increased. PMID:26558151

  1. Cloning of DNA fragments: ligation reactions in agarose gel.

    PubMed

    Furtado, Agnelo

    2014-01-01

    Ligation reactions to ligate a desired DNA fragment into a vector can be challenging to beginners and especially if the amount of the insert is limiting. Although additives known as crowding agents, such as PEG 8000, added to the ligation mixes can increase the success one has with ligation reactions, in practice the amount of insert used in the ligation can determine the success or the failure of the ligation reaction. The method described here, which uses insert DNA in gel slice added directly into the ligation reaction, has two benefits: (a) using agarose as the crowding agent and (b) reducing steps of insert purification. The use of rapid ligation buffer and incubation of the ligation reaction at room temperature greatly increase the efficiency of the ligation reaction even for blunt-ended ligation. PMID:24243199

  2. Modified Sugiura Operation for Idiopathic Portal Hypertension with Bleeding Oesophageal Varices. A Case Report.

    PubMed

    Schettini, A-V; Pinheiro, R S; Pescatore, P; Lerut, J

    2015-01-01

    A case of a 36 years old man presenting massive upper GI bleeding due to oesophageal varices developed in the context of an idiopathic portal cavernoma and extensive porto-splenic thrombosis is discussed. He underwent a successful modified Sugiura operation (oesophago-gastric devascularisation and splenectomy [OGDS]) completed with interventional endoscopic treatment of residual oesophageal varices. The benefit of the modified Sugiura procedure proposed for the treatment of upper GI variceal bleeding developed in the context of splanchnic venous thrombosis is discussed. The procedure is a valid therapy in the treatment of symptomatic extra-hepatic hypertension when other options are inapplicable. PMID:26158259

  3. Enteroscopic Management of Ectopic Varices in a Patient with Liver Cirrhosis and Portal Hypertension.

    PubMed

    Watson, G A; Abu-Shanab, A; O'Donohoe, R L; Iqbal, M

    2016-01-01

    Portal hypertension and liver cirrhosis may predispose patients to varices, which have a propensity to bleed and cause significant morbidity and mortality. These varices are most commonly located in the gastroesophageal area; however, rarely ectopic varices may develop in unusual locations outside of this region. Haemorrhage from these sites can be massive and difficult to control; thus early detection and management may be lifesaving. We present a case of occult gastrointestinal bleeding in a patient with underlying alcoholic liver disease where an ectopic varix was ultimately detected with push enteroscopy. PMID:27595025

  4. Embolization therapy for bleeding from jejunal loop varices due to extrahepatic portal vein obstruction.

    PubMed

    Yoshimatsu, Rika; Yamagami, Takuji; Ishikawa, Masaki; Kajiwara, Kenji; Kakizawa, Hideaki; Hiyama, Eiso; Tashiro, Hirotaka; Murakami, Yoshiaki; Ohge, Hiroki; Awai, Kazuo

    2016-01-01

    Four patients underwent embolization therapy for hemorrhage from varices in the jejunal loop after choledochojejunostomy existing in hepatopetal collateral veins due to chronic extrahepatic portal vein obstruction through the afferent veins using microcoils and/or n-butyl cyanoacrylate. In all four patients, all afferent veins were successfully embolized and successful hemostasis was achieved without liver dysfunction. However, recurrence of the varices and rebleeding occurred within a year in two patients. Embolization for hemorrhage from varices in the jejunal loop after choledochojejunostomy through afferent veins is acceptable in terms of safety and is useful to achieve hemostasis in emergency circumstances. PMID:26330264

  5. Splenic infarction after N-butyl-2-cyanoacrylate injection for gastric varices: why does it happen?

    PubMed

    Köksal, Aydin S; Kayaçetin, Ertuğrul; Torun, Serkan; Erkan, Vedat; Ökten, Riza S

    2013-10-01

    Recent guidelines and consensus reports recommend endoscopic injection therapy with N-butyl-2-cyanoacrylate as the first-line treatment for bleeding-isolated gastric varices and gastroesophageal varices types 1 and 2. Embolization is a rare but serious complication of cyanoacrylate injection, which may be fatal in some cases. Herein, we present a patient who developed splenic infarction after N-butyl-cyanoacrylate injection for gastroesophageal varices type 2 and discuss the potential reasons and tips to prevent the occurence of embolization.

  6. Enteroscopic Management of Ectopic Varices in a Patient with Liver Cirrhosis and Portal Hypertension

    PubMed Central

    Abu-Shanab, A.

    2016-01-01

    Portal hypertension and liver cirrhosis may predispose patients to varices, which have a propensity to bleed and cause significant morbidity and mortality. These varices are most commonly located in the gastroesophageal area; however, rarely ectopic varices may develop in unusual locations outside of this region. Haemorrhage from these sites can be massive and difficult to control; thus early detection and management may be lifesaving. We present a case of occult gastrointestinal bleeding in a patient with underlying alcoholic liver disease where an ectopic varix was ultimately detected with push enteroscopy. PMID:27595025

  7. Hemodynamic changes in a patient with esophageal varices after endoscopic injection sclerotherapy evaluated by endoscopic color Doppler ultrasonography.

    PubMed

    Sato, Takahiro; Yamazaki, Katsu; Ohmura, Takumi; Suga, Toshihiro

    2007-03-01

    A 46-year-old man with alcoholic cirrhosis was admitted to our hospital for treatment of high-risk esophageal varices in February 2000. Images of the esophageal varices, paraesophageal veins and palisade veins were obtained by endoscopic color Doppler ultrasonography (ECDUS) before endoscopic injection sclerotherapy (EIS). Prophylactic EIS was performed six times per week for esophageal varices, and EIS was continued until the esophageal varices were completely eradicated. In July 2002, endoscopy revealed esophageal varices graded as Cb, F1, Lm, and RC(-), and color flow images of the palisade veins (hepatofugal flow), esophageal varices, and a developed paraesophageal vein were obtained with ECDUS. In April 2003, endoscopy showed esophageal varices graded as Cb, F1, Lm, and RC(-), and color flow images of the palisade veins and esophageal varices were obtained using ECDUS. The blood in the palisade veins flowed in an alternate direction on color flow images, and pulsatile waves were delineated at the gastroesophageal junction. In January 2004, endoscopy revealed esophageal varices graded as F0 and RC(-), and pulsatile waves were delineated in the lower esophagus with ECDUS. However, the esophageal varices and palisade veins had disappeared from color flow images. In conclusion, ECDUS was useful for evaluating hemodynamic changes after EIS.

  8. A comparative study of conventional ligation and self-ligation bracket systems.

    PubMed

    Shivapuja, P K; Berger, J

    1994-11-01

    The increased use of self-ligating bracket systems frequently raises the question of how they compare with conventional ligation systems. An in vitro and clinical investigation was undertaken to evaluate and compare these distinctly different groups, by using five different brackets. The Activa ("A" Company, Johnson & Johnson, San Diego, Calif.), Edgelok (Ormco, Glendora, Calif.), and SPEED (Strite Industries Ltd., Cambridge, Ontario) self-ligating bracket systems displayed a significantly lower level of frictional resistance, dramatically less chairtime for arch wire removal and insertion, and promoted improved infection control, when compared with polyurethane elastomeric and stainless steel tie wire ligation for ceramic and metal twin brackets. PMID:7977187

  9. The changing spectrum of treatment for variceal bleeding.

    PubMed Central

    Rikkers, L F

    1998-01-01

    OBJECTIVE: The objective of this study was to assess the impact of endoscopic therapy, liver transplantation, and transjugular intrahepatic portosystemic shunt (TIPS) on patient selection and outcome of surgical treatment for this complication of portal hypertension, as reflected in a single surgeon's 18-year experience with operations for variceal hemorrhage. SUMMARY BACKGROUND DATA: Definitive treatment of patients who bleed from portal hypertension has been progressively altered during the past 2 decades during which endoscopic therapy, liver transplantation, and TIPS have successively become available as alternative treatment options to operative portosystemic shunts and devascularization procedures. METHODS: Two hundred sixty-three consecutive patients who were surgically treated for portal hypertensive bleeding between 1978 and 1996 were reviewed retrospectively. Four Eras separated by the dates when endoscopic therapy (January 1981), liver transplantation (July 1985), and TIPS (January 1993) became available in our institution were analyzed. Throughout all four Eras, a selective operative approach, using the distal splenorenal shunt (DSRS), nonselective shunts, and esophagogastric devascularization, was taken. The most common indications for nonselective shunts and esophagogastric devascularization were medically intractable ascites and splanchnic venous thrombosis, respectively. Most other patients received a DSRS. RESULTS: The risk status (Child's class) of patients undergoing surgery progressively improved (p = 0.001) throughout the 4 Eras, whereas the need for emergency surgery declined (p = 0.002). The percentage of nonselective shunts performed decreased because better options to manage acute bleeding episodes (sclerotherapy, TIPS) and advanced liver disease complicated by ascites (liver transplantation, TIPS) became available (p = 0.009). In all Eras, the operative mortality rate was directly related to Child's class (A, 2.7%; B, 7.5%; and C, 26

  10. Endoscopic submucosal dissection combined with endoscopic injection sclerotherapy for early gastric cancer on gastric fundal varices.

    PubMed

    Uno, Kaname; Iijima, Katsunori; Koike, Tomoyuki; Abe, Yasuhiko; Asano, Naoki; Yokosawa, Satoshi; Imatani, Akira; Shimosegawa, Tooru

    2012-08-01

    Currently, there is little report of treatment strategy for early gastric cancer (EGC) on gastric fundal varices (GFVs), because controlling GFVs was more challenging than controlling gastric cardiac varices associated with esophageal varices. We first report effective endoscopic treatment of EGC on GFVs of a 77-year-old man with Child-B cirrhosis. Endoscopic ultrasound and multidetector-row computed tomography studies revealed intramucosal EGC on variceal components, supplied from posterior gastric vein and drained to subphrenic vein without gastrorenal shunt. With informed consent, we performed endoscopic submucosal dissection (ESD) after eradication of GFVs by endoscopic injection sclerotherapy (EIS). Histologic assessment revealed curability of ESD and inflammation and fibrosis around EIS site. Thereafter, no recurrence and complication had occurred. To avoid life-threatening bleeding from GFVs, we achieved complete resection by ESD under direct visualization of submucosa after eradication of GFVs by EIS based on the examination of hemodynamics and local relationship between EGC and GFVs.

  11. Splenic artery embolization for the treatment of bleeding gastric varices secondary to splenic vein thrombosis.

    PubMed

    Stone, Patrick A; Phang, David; Richmond, Bryan; Gill, Gurpreet; Campbell, John E

    2014-04-01

    Splenic vein thrombosis can lead to gastric varices. Subsequent upper gastrointestinal bleeding may ensue related to the change in venous outflow to the portal system. Vascular surgeons are infrequently asked to assist in the management of this entity. However, with many vascular surgeons providing diverse endovascular-based interventions, understanding catheter-based solutions is imperative. This report presents a case in which arterial embolization was used to treat gastric variceal bleeding.

  12. Long Term Variceal Sclerotherapy: Is Endoscopic Sclerosis a Unique Therapeutic Approach and a True Alternative to Surgery?

    PubMed Central

    Lazar, A.; Rambach, W.

    1991-01-01

    Endoscopic sclerotherapy has been used to control acute variceal haemorrhage which persists despite conservative therapy, prevent recurrent variceal haemorrhage in patients with a history of oesophageal haemorrhage, and to prevent a haemorrhage in patients with oesophageal varices who never bled. In this short paper I will cover our personal experience with more than 2000 patients receiving particularly paravariceal endoscopic sclerotherapy of bleeding esophageal varices, and especially present the results of our prospective and controlled randomized trials (Table 1) and underline the thesis that endoscopic sclerotherapy and surgical procedures for patients with portal hypertension are complementary supporting measures or options. PMID:1911473

  13. Endoscopic treatment of gastric varices bleeding with the use of n-butyl-2 cyanoacrylate

    PubMed Central

    Kobryń, Konrad; Paluszkiewicz, Rafał; Krawczyk, Marek; Wróblewski, Tadeusz

    2015-01-01

    Introduction Oesophageal varices and gastric varices are naturally-formed, pathological portosystemic shunts that occur in patients with portal hypertension. Gastric varices are responsible for about 10% of variceal bleeding; however, they are also the cause of massive haemorrhage, often with dramatic progress. Aim To assess the results of endoscopic treatment of gastrointestinal bleeding from oesophageal and gastric varices using tissue glue Histoacryl. Material and methods From January 2013 to May 2015 170 patients underwent a total of 244 obliterations with the administration of tissue glue due to gastroesophageal varices. We analysed 35 patients who received urgent endoscopic intervention due to life-threatening gastric variceal bleeding. Results Thirty-five patients underwent 47 endoscopic procedures of haemorrhage management. Immediate haemostasis was achieved in 32 (91.4%) patients. In 3 (8.6%) cases endoscopy failed. In 2 patients a Linton tube was applied before secondary endoscopy. A single trans jugular portosystemic shunt (TIPS) was performed. Permanent haemostasis during the first endoscopy was achieved in 26 (74%) patients. Six (17%) patients presented recurrent bleeding 1–4 days following the initial treatment. Three patients had a splenic artery embolisation performed. One of the embolised patients required surgery, and a splenectomy was carried out. Conclusions If this kind of therapy is unavailable at the time, it is advised that one of the conventional methods of controlling bleeding is used, introducing basic life support and transporting the patient to a specialist centre with adequate endoscopic facilities, radiological possibilities of endovascular intervention, and surgical treatment of liver transplantation. PMID:26759632

  14. Bleeding Duodenal Varices Successfully Treated with Balloon-Occluded Retrograde Transvenous Obliteration (B-RTO) Assisted by CT During Arterial Portography

    SciTech Connect

    Tsurusaki, Masakatsu Sugimoto, Koji; Matsumoto, Shinichi; Izaki, Kenta; Fukuda, Tetsuya; Akasaka, Yoshinobu; Fujii, Masahiko; Hirota, Shozo; Sugimura, Kazuro

    2006-12-15

    A 60-year-old woman with massive hemorrhage from duodenal varices was transferred to our hospital for the purpose of transcatheter intervention. Although digital subtraction arterial portography could not depict the entire pathway of collateral circulation, the efferent route of the duodenal varices was clearly demonstrated on subsequent CT during arterial portography. Balloon-occluded retrograde transvenous obliteration (B-RTO) of the varices was performed via the efferent vein and achieved complete thrombosis of the varices.

  15. Increasing the efficiency of SAGE adaptor ligation by directed ligation chemistry

    PubMed Central

    So, Austin P.; Turner, Robin F. B.; Haynes, Charles A.

    2004-01-01

    The ability of Serial Analysis of Gene Expression (SAGE) to provide a quantitative picture of global gene expression relies not only on the depth and accuracy of sequencing into the SAGE library, but also on the efficiency of each step required to generate the SAGE library from the starting mRNA material. The first critical step is the ligation of adaptors containing a Type IIS recognition sequence to the anchored 3′ end cDNA population that permits the release of short sequence tags (SSTs) from defined sites within the 3′ end of each transcript. Using an in vitro transcript as a template, we observed that only a small fraction of anchored 3′ end cDNA are successfully ligated with added SAGE adaptors under typical reaction conditions currently used in the SAGE protocol. Although the introduction of ∼500-fold molar excess of adaptor or the inclusion of 15% (w/v) PEG-8000 increased the yield of the adaptor-modified product, complete conversion to the desired adaptor:cDNA hetero-ligation product is not achieved. An alternative method of ligation, termed as directed ligation, is described which exploits a favourable mass-action condition created by the presence of NlaIII during ligation in combination with a novel SAGE adaptor containing a methylated base within the ligation site. Using this strategy, we were able to achieve near complete conversion of the anchored 3′ end cDNA into the desired adaptor-modified product. This new protocol therefore greatly increases the probability that a SST will be generated from every transcript, greatly enhancing the fidelity of SAGE. Directed ligation also provides a powerful means to achieve near-complete ligation of any appropriately designed adaptor to its respective target. PMID:15247329

  16. Treatment of gastric varices with partial splenic embolization in a patient with portal vein thrombosis and a myeloproliferative disorder.

    PubMed

    Gianotti, Robert; Charles, Hearns; Hymes, Kenneth; Chandarana, Hersh; Sigal, Samuel

    2014-10-21

    Therapeutic options for gastric variceal bleeding in the presence of extensive portal vein thrombosis associated with a myeloproliferative disorder are limited. We report a case of a young woman who presented with gastric variceal bleeding secondary to extensive splanchnic venous thrombosis due to a Janus kinase 2 mutation associated myeloproliferative disorder that was managed effectively with partial splenic embolization.

  17. The Role of Spleen Stiffness in Determining the Severity and Bleeding Risk of Esophageal Varices in Cirrhotic Patients

    PubMed Central

    Kim, Hwi Young; Jin, Eun Hyo; Kim, Won; Lee, Jae Young; Woo, Hyunsik; Oh, Sohee; Seo, Ji-Yeon; Oh, Hong Sang; Chung, Kwang Hyun; Jung, Yong Jin; Kim, Donghee; Kim, Byeong Gwan; Lee, Kook Lae

    2015-01-01

    Abstract Esophageal varix and its hemorrhage are serious complications of liver cirrhosis. Recent studies have focused on noninvasive prediction of esophageal varices. We attempted to evaluate the association of liver and spleen stiffness (LS and SS) as measured by acoustic radiation force impulse imaging, with the presence and severity of esophageal varices and variceal hemorrhage in cirrhotic patients. We measured LS and SS, along with endoscopic examination of esophageal varices for a total of 125 cirrhotic patients at a single referral hospital in this prospective observational study. The diagnostic utility of noninvasive methods for identifying varices and their bleeding risk was compared, including LS, SS, spleen length, Child-Pugh score, and various serum fibrosis indices. Esophageal varices were present in 77 patients (61.6%). SS was significantly higher in patients with varices than in those without varices (3.58 ± 0.47 vs 3.02 ± 0.49; P < 0.001). A tendency toward increasing SS levels was observed with increasing severity of varices (no varix, 3.02 ± 0.49; F1, 3.39 ± 0.51; F2, 3.60 ± 0.42; F3, 3.85 ± 0.37; P < 0.001). SS was significantly higher in patients who experienced variceal hemorrhage than in those who did not (3.80 ± 0.36 vs 3.20 ± 0.51; P = 0.002). An optimal cut-off value of SS for high-risk varices (≥F2) or variceal hemorrhage was 3.40 m/s. SS was significantly correlated with the presence, severity, and bleeding risk of esophageal varices. Prompt endoscopic evaluation of variceal status and prophylactic measures based on the SS may be warranted for cirrhotic patients. PMID:26091449

  18. Tracheal varices caused by mediastinal compression of a large intrathoracic goiter: report of a case

    PubMed Central

    LUCCHINI, R.; SANTOPRETE, S.; TRIOLA, R.; POLISTENA, A.; MONACELLI, M.; AVENIA, S.; SANGUINETTI, A.; PUMA, F.; AVENIA, N.

    2015-01-01

    Introduction Tracheal varices are a rare condition but they can be an important source of massive or recurrent haemoptysis. Usually they are related to increased pressure in the pulmonary veins. Mediastinal goiter is often associated to compressive effects on the surrounding structures, including mediastinal vessels with potential superior vena cava syndrome. Case report We describe a case, not previously reported in literature, of mediastinal goiter with hemoptysis as first clinical manifestation. Bleeding was attributed to a superior vena cava syndrome associated to a tracheal fragile mucosa with an easily bleeding intramural nodule which was diagnosed as tracheal varices after total thyroidectomy. The nodule in fact disappeared together with the venous hypertensive signs after venous decompression of the mediastinum. Conclusions Compressive symptoms including tracheal varices, related to mediastinal goiter, can be treated surgically by total thyroidectomy via cervicotomy and when required with associated median sternotomy. PMID:25827666

  19. Severe gastric variceal bleeding successfully treated by emergency splenic artery embolization.

    PubMed

    Sankararaman, Senthilkumar; Velayuthan, Sujithra; Vea, Romulo; Herbst, John

    2013-06-01

    Bleeding from gastric varices due to splenic vein obstruction is extremely rare in children, but it can be catastrophic. Reported herein is the case of a teenager with splenic vein thrombosis and chronic decompensated liver disease from autoimmune hepatitis who presented with massive gastric variceal bleeding. Standard medical management did not control the bleeding. Due to decompensated liver disease and continuous active bleeding, emergency partial splenic artery embolization was preferred over splenectomy or a shunt procedure. Bleeding was successfully controlled by partial splenic artery embolization by decreasing the inflow of blood into the portal system. It is concluded that emergency partial splenic artery embolization is a safer alternative life-saving procedure to manage severe gastric variceal bleeding due to splenic vein obstruction in a patient with high surgical risk. To our knowledge, only one other patient with similar management has been reported in the pediatric age group.

  20. Influence of variceal bleeding on natural history of ACLF and management options.

    PubMed

    Al-Mahtab, Mamun; Akbar, Sheikh Mohammad Fazle; Garg, Hitendra

    2016-05-01

    Patients with diagnosed and undiagnosed chronic liver diseases experience one or more acute assaults of a hepatic nature and develop a downhill course of liver diseases, a condition regarded as acute-on-chronic liver failure (ACLF). It is a medical emergency, the prognosis of ACLF is extremely bad and considerable numbers of patients with ACLF die even after diagnosis and receiving conservative treatment. ACLF is characterized by jaundice, coagulopathy, ascites and encephalopathy. ACLF patients are very sick and associated with different hemodynamic profiles and have very high 3-month mortality. As these groups of patients have high baseline hepatic venous pressure gradients, the chances of variceal bleed are also high, and the impact is also greater in comparison to stable cirrhosis; however, evidence is lacking to substantiate such effects. The aim of this review is to discuss the natural course of variceal bleeding in ACLF patients and to develop insights into the management of variceal bleeding in ACLF.

  1. No Mortality Difference Following Treatment with Terlipressin or Somatostatin in Cirrhotic Patients with Gastric Variceal Hemorrhage

    PubMed Central

    Hung, Tsung-Hsing; Tsai, Chen-Chi; Tseng, Kuo-Chih; Hsieh, Yu-Hsi; Tseng, Chih-Wei

    2016-01-01

    Background/Aims: The aim of this study was to compare the efficacy of terlipressin versus somatostatin as adjuvants to endoscopic treatment in cirrhotic patients with gastric variceal bleeding. Patients and Methods: The National Health Insurance Database, derived from the Taiwan National Health Insurance Program, was used to enroll patients who were discharged with International Classification of Diseases, 9th Revision, Clinical Modification diagnoses of cirrhosis and who underwent gastric variceal sclerotherapy for gastric variceal bleeding between January 1, 2007, and December 31, 2007. We observed treatment outcomes and identified clinical factors associated with mortality. Results: In total, we enrolled 311 cirrhosis patients who underwent sclerotherapy for active gastric variceal bleeding. Among them, 218 patients received terlipressin, and 93 patients received somatostatin. The overall 30 day mortality rate was 13.2% (41/311). A total of 78 (25.1%) patients underwent second-look endoscopy, but only 12 (7%) needed a second course of gastric variceal sclerotherapy. The overall 30-day mortality rates for patients treated with terlipressin and somatostatin were 13.3% and 12.9%, respectively, showing no statistically significant differences between outcomes in the two treatment groups (P = 0.672). The risk of 30-day mortality was significantly higher in patients with hepatocellular carcinoma (HR: 3.257, 95% CI: 1.640-6.469, P= 0.001), acute renal failure (HR: 6.261, 95% CI: 2.376-16.499, P < 0.001), or hepatic encephalopathy (HR: 3.091, 95% CI: 1.430-6.680, P= 0.004). Conclusions: Mortality rates did not differ significantly between cirrhosis patients with acute gastric variceal bleeding who received somatostatin or terlipressin as adjuvants to endoscopy. PMID:27184641

  2. Utility of endoscopic ultrasound in the diagnosis and management of esophagogastric varices

    PubMed Central

    Wang, An-Jiang; Li, Bi-Min; Zheng, Xue-Lian; Shu, Xu; Zhu, Xuan

    2016-01-01

    Endoscopic ultrasound (EUS) has significantly improved our understanding of the complex vascular structural changes in patients with portal hypertension. At present, EUS is a useful diagnostic tool for the evaluation of esophagogastric varices (EGVs) and guidance of endoscopic therapy. Several studies have employed this new technique for the diagnosis and management of esophageal and gastric varices, respectively. In the present review, we have summarized the current status of EUS for the diagnosis and management of EGVs and clarified the clinical feasibility of this procedure. New indications for EUS can be developed in the future after adequate validation. PMID:27503152

  3. [Prevention of the 1st bleeding of esophageal varices: review of the literature and clinical experience].

    PubMed

    Di Lecce, F; Contini, S

    1990-01-01

    The authors present a review of the literature on prophylactic sclerosis of esophageal varices in cirrhotics, taking as a starting point their personal experience. The natural history of varices and the criteria of their hemorrhagic risk are described; moreover are presented the results of the most important controlled studies of prophylactic surgery, sclerosis and beta-blocking drugs. In spite of the rather encouraging results after sclerosis at the long-term follow-up and the promising aspects of beta-blocking agents, it is not felt to recommend, according to the literature, a routine application of prophylactic sclerosis, a procedure which should be reserved to leading centers in controlled studies.

  4. Diagnostic non-invasive model of large risky esophageal varices in cirrhotic hepatitis C virus patients

    PubMed Central

    Elalfy, Hatem; Elsherbiny, Walid; Abdel Rahman, Ashraf; Elhammady, Dina; Shaltout, Shaker Wagih; Elsamanoudy, Ayman Z; El Deek, Bassem

    2016-01-01

    AIM To build a diagnostic non-invasive model for screening of large varices in cirrhotic hepatitis C virus (HCV) patients. METHODS This study was conducted on 124 post-HCV cirrhotic patients presenting to the clinics of the Endemic Medicine Department at Mansoura University Hospital for evaluation before HCV antiviral therapy: 78 were Child A and 46 were Child B (score ≤ 8). Inclusion criteria for patients enrolled in this study was presence of cirrhotic HCV (diagnosed by either biopsy or fulfillment of clinical basis). Exclusion criteria consisted of patients with other etiologies of liver cirrhosis, e.g., hepatitis B virus and patients with high MELD score on transplant list. All patients were subjected to full medical record, full basic investigations, endoscopy, and computed tomography (CT), and then divided into groups with no varices, small varices, or large risky varices. In addition, values of Fibrosis-4 score (FIB-4), aminotransferase-to-platelet ratio index (APRI), and platelet count/splenic diameter ratio (PC/SD) were also calculated. RESULTS Detection of large varies is a multi-factorial process, affected by many variables. Choosing binary logistic regression, dependent factors were either large or small varices while independent factors included CT variables such coronary vein diameter, portal vein (PV) diameter, lieno-renal shunt and other laboratory non-invasive variables namely FIB-4, APRI, and platelet count/splenic diameter. Receiver operating characteristic (ROC) curve was plotted to determine the accuracy of non-invasive parameters for predicting the presence of large esophageal varices and the area under the ROC curve for each one of these parameters was obtained. A model was established and the best model for prediction of large risky esophageal varices used both PC/SD and PV diameter (75% accuracy), while the logistic model equation was shown to be (PV diameter × -0.256) plus (PC/SD × -0.006) plus (8.155). Values nearing 2 or more denote

  5. Diagnostic non-invasive model of large risky esophageal varices in cirrhotic hepatitis C virus patients

    PubMed Central

    Elalfy, Hatem; Elsherbiny, Walid; Abdel Rahman, Ashraf; Elhammady, Dina; Shaltout, Shaker Wagih; Elsamanoudy, Ayman Z; El Deek, Bassem

    2016-01-01

    AIM To build a diagnostic non-invasive model for screening of large varices in cirrhotic hepatitis C virus (HCV) patients. METHODS This study was conducted on 124 post-HCV cirrhotic patients presenting to the clinics of the Endemic Medicine Department at Mansoura University Hospital for evaluation before HCV antiviral therapy: 78 were Child A and 46 were Child B (score ≤ 8). Inclusion criteria for patients enrolled in this study was presence of cirrhotic HCV (diagnosed by either biopsy or fulfillment of clinical basis). Exclusion criteria consisted of patients with other etiologies of liver cirrhosis, e.g., hepatitis B virus and patients with high MELD score on transplant list. All patients were subjected to full medical record, full basic investigations, endoscopy, and computed tomography (CT), and then divided into groups with no varices, small varices, or large risky varices. In addition, values of Fibrosis-4 score (FIB-4), aminotransferase-to-platelet ratio index (APRI), and platelet count/splenic diameter ratio (PC/SD) were also calculated. RESULTS Detection of large varies is a multi-factorial process, affected by many variables. Choosing binary logistic regression, dependent factors were either large or small varices while independent factors included CT variables such coronary vein diameter, portal vein (PV) diameter, lieno-renal shunt and other laboratory non-invasive variables namely FIB-4, APRI, and platelet count/splenic diameter. Receiver operating characteristic (ROC) curve was plotted to determine the accuracy of non-invasive parameters for predicting the presence of large esophageal varices and the area under the ROC curve for each one of these parameters was obtained. A model was established and the best model for prediction of large risky esophageal varices used both PC/SD and PV diameter (75% accuracy), while the logistic model equation was shown to be (PV diameter × -0.256) plus (PC/SD × -0.006) plus (8.155). Values nearing 2 or more denote

  6. A fourfold increase of oesophageal variceal bleeding in cirrhotic patients with a history of oesophageal variceal bleeding

    PubMed Central

    Hung, Tsung-Hsing; Tseng, Chih-Wei; Tsai, Chih-Chun; Lay, Chorng-Jang; Tsai, Chen-Chi

    2016-01-01

    INTRODUCTION Large, recent population-based data for evaluating the predictors of oesophageal variceal bleeding (OVB) among cirrhotic patients is still lacking. This study aimed to determine the cumulative incidence of OVB among cirrhotic patients and identify the predictors of OVB occurrence. METHODS Patient information on 38,172 cirrhotic patients without a history of OVB, who were discharged between 1 January 2007 and 31 December 2007, was obtained from the Taiwan National Health Insurance Database for this study. All patients were followed up for three years. Death was the competing risk when calculating the cumulative incidences and hazard ratios (HRs) of OVB. RESULTS OVB was present in 2,609 patients (OVB group) and absent in 35,563 patients (non-OVB group) at hospitalisation. During the three-year follow-up period, the cumulative incidence of OVB was 44.5% and 11.3% in the OVB and non-OVB group, respectively (p < 0.001). Modified Cox regression analysis showed that the HR of OVB history was 4.42 for OVB occurrence (95% confidence interval [CI] 4.13–4.74). Other predictors for OVB occurrence included hepatocellular carcinoma (HR 1.16, 95% CI 1.09–1.24), young age (HR 0.98, 95% CI 0.98–0.98), ascites (HR 1.46, 95% CI 1.37–1.56), alcohol-related disorders (HR 1.20, 95% CI 1.12–1.28), peptic ulcer bleeding (HR 1.26, 95% CI 1.13–1.41) and diabetes mellitus (HR 1.14, 95% CI 1.06–1.23). CONCLUSION Cirrhotic patients have a fourfold increased risk of future OVB following the first incidence of OVB. PMID:26768323

  7. Pancreatic carcinoma presenting as bleeding from segmental gastric varices: pitfalls in diagnosis.

    PubMed Central

    Mullan, F. J.; McKelvey, S. T.

    1990-01-01

    Splenic vein occlusion leading to gastric variceal haemorrhage should be considered in cases of obscure upper gastrointestinal bleeding. We report an unusual case in which the underlying pathology was a resectable carcinoma of the pancreatic tail. Images Figure 1 PMID:2371194

  8. Severe bleeding from esophageal varices resistant to endoscopic treatment in a non cirrhotic patient with portal hypertension

    PubMed Central

    Caronna, Roberto; Bezzi, Mario; Schiratti, Monica; Cardi, Maurizio; Prezioso, Giampaolo; Benedetti, Michele; Papini, Federica; Mangioni, Simona; Martino, Gabriele; Chirletti, Piero

    2008-01-01

    A non cirrhotic patient with esophageal varices and portal vein thrombosis had recurrent variceal bleeding unsuccessfully controlled by endoscopy and esophageal transection. Emergency transhepatic portography confirmed the thrombosed right branch of the portal vein, while the left branch appeared angulated, shifted and stenotic. A stent was successfully implanted into the left branch and the collateral vessels along the epatoduodenal ligament disappeared. In patients with esophageal variceal hemorrhage and portal thrombosis if endoscopy fails, emergency esophageal transection or nonselective portocaval shunting are indicated. The rare patients with only partial portal thrombosis can be treated directly with stenting through an angioradiologic approach. PMID:18644135

  9. Usefulness of Transjugular Intrahepatic Portosystemic Shunt in the Management of Bleeding Ectopic Varices in Cirrhotic Patients

    SciTech Connect

    Vidal, V.; Joly, L.; Perreault, P.; Bouchard, L.; Lafortune, M.; Pomier-Layrargues, G.

    2006-04-15

    Purpose. To evaluate the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) in the control of bleeding from ectopic varices. Methods. From 1995 to 2004, 24 cirrhotic patients, bleeding from ectopic varices, mean age 54.5 years (range 15-76 years), were treated by TIPS. The etiology of cirrhosis was alcoholic in 13 patients and nonalcoholic in 11 patients. The location of the varices was duodenal (n = 5), stomal (n = 8), ileocolic (n = 6), anorectal (n = 3), umbilical (n = 1), and peritoneal (n 1). Results. TIPS controlled the bleeding in all patients and induced a decrease in the portacaval gradient from 19.7 {+-} 5.4 to 6.4 {+-} 3.1 mmHg. Postoperative complications included self-limited intra-abdominal bleeding (n = 2), self-limited hemobilia (n = 1), acute thrombosis of the shunt (n = 1), and bile leak treated by a covered stent (n = 1). Median follow-up was 592 days (range 28-2482 days). Rebleeding occurred in 6 patients. In 2 cases rebleeding was observed despite a post-TIPS portacaval gradient lower than 12 mmHg and was controlled by variceal embolization; 1 patient underwent surgical portacaval shunt and never rebled; in 3 patients rebleeding was related to TIPS stenosis and treated with shunt dilatation with addition of a new stent. The cumulative rate of rebleeding was 23% and 31% at 1 and 2 years, respectively. One- and 2-year survival rates were 80% and 76%, respectively. Conclusion. The present series demonstrates that bleeding from ectopic varices, a challenging clinical problem, can be managed safely by TIPS placement with low rebleeding and good survival rates.

  10. Esophageal transection with automatic stapler device for bleeding esophageal varices. Case report and review of the literature.

    PubMed

    Bayer, I; Kyzer, S; Chaimoff, C

    1989-01-01

    The EEA stapler offers a relative easy technique for the control of severe bleeding from esophageal varices. Two cases are reported in which this technique in combination with proximal gastric devascularization and splenectomy was found to be superior to the performance of portosystemic shunt in emergency cases. The results of portocaval shunts created during severe bleeding from esophageal varices are not satisfactory because of the high mortality rate varying between 36% and 47% (1, 2) and the development of postoperative encephalopathy. For these reasons the tendency today, in cases of severe bleeding from esophageal varices where conservative treatment was unsuccessful, is that the surgeon should attack the bleeding area itself (3). Support for this opinion may be found in the publications of Sugiura and Futagawa (4, 5) and of Koyama et al. (6) about their long-term good results obtained after esophageal transection for bleeding esophageal varices. PMID:2785322

  11. The effects of LAA ligation on LAA electrical activity

    PubMed Central

    Lakkireddy, Dhanunjaya; Rojas, Francia; Bednarek, Jacek; Kapelak, Boguslaw; Bartus, Magdalena; Sadowski, Jerzy; Badhwar, Nitish; Earnest, Mathew; Valderrabano, Miguel; Lee, Randall J.

    2015-01-01

    BACKGROUND The arrhythmic role of the left atrial appendage (LAA) has been implicated in the maintenance of persistent atrial fibrillation. LAA isolation with catheter ablation has been successful but is limited by the risk of tamponade and electromechanical dissociation with the potential for LAA thrombus formation. OBJECTIVE To assess whether LAA ligation results in LAA electrical isolation. METHODS A total of 68 patients with contraindication or intolerance to oral anticoagulation therapy underwent LAA ligation with the LARIAT suture delivery device. Patients had unipolar [n = 30 (44%)] or bipolar [n = 38(56%)] voltage measurements pre- and post-LAA ligation. RESULTS All 68 patients underwent successful LAA ligation. There was a statistically significant reduction in the mean LAA voltage from pre-ligation (unipolar pre-ligation voltage 1.1 ± 0.53 mV; bipolar pre-ligation voltage 4.7 ± 2.83 mV) to post-ligation (unipolar post-ligation voltage 0.3 ± 0.38 mV; bipolar post-ligation voltage 0.6 ± 0.27 mV). Ninety-four percent of the patients had a reduction in the LAA voltage after the closure of the snare, with 10 of 30 (33%) of the patients having complete elimination of LAA voltage with the initial tightening of the suture. Pacing from the LAA after the closure of the snare resulted in lack of capture of the left atrium in 28 of 31 patients. CONCLUSIONS The snare closure of the LAA using the LARIAT device produces an acute reduction in the LAA voltage and inhibits the capture of the left atrium during LAA pacing. Future studies are needed to determine whether LAA ligation affects atrial fibrillation burden. PMID:24444443

  12. Upper non-variceal gastrointestinal bleeding - review the effectiveness of endoscopic hemostasis methods

    PubMed Central

    Szura, Mirosław; Pasternak, Artur

    2015-01-01

    Upper non-variceal gastrointestinal bleeding is a condition that requires immediate medical intervention and has a high associated mortality rate (exceeding 10%). The vast majority of upper gastrointestinal bleeding cases are due to peptic ulcers. Helicobacter pylori infection, non-steroidal anti-inflammatory drugs and aspirin are the main risk factors for peptic ulcer disease. Endoscopic therapy has generally been recommended as the first-line treatment for upper gastrointestinal bleeding as it has been shown to reduce recurrent bleeding, the need for surgery and mortality. Early endoscopy (within 24 h of hospital admission) has a greater impact than delayed endoscopy on the length of hospital stay and requirement for blood transfusion. This paper aims to review and compare the efficacy of the types of endoscopic hemostasis most commonly used to control non-variceal gastrointestinal bleeding by pooling data from the literature. PMID:26421105

  13. Prospective randomized comparison of sodium tetradecyl sulfate and polidocanol as variceal sclerosing agents.

    PubMed

    Bhargava, D K; Singh, B; Dogra, R; Dasarathy, S; Sharma, M P

    1992-02-01

    A prospective randomized controlled study was designed to evaluate differences in efficacy and complication rate between the two most commonly used sclerosing agents, sodium tetradecyl sulfate (STD) and polidocanol. Of 52 patients with esophageal variceal bleeding, 26 were randomized to receive sclerotherapy with 1.5% STD and 26 to receive 1% polidocanol at weekly intervals. Eradication of varices was achieved in 88% patients each of the STD and polidocanol group. There was no significant difference between patients injected with STD and polidocanol with regard to re-bleeding (27% vs. 15%) and mortality (11.5% in both). The use of STD, in contrast to polidocanol, was associated with a higher incidence of complications in terms of severe retrosternal pain (27% vs. 4%), deep ulceration (53% vs. 23%), dysphagia (88% vs. 46%), and stricture formation (27% vs. 8%). It was concluded that these two agents were similar in efficacy. However, polidocanol was superior due to a lower incidence of complications.

  14. Gastric variceal bleeding due to pancreatitis-induced splenic vein thrombosis.

    PubMed

    Gotto, Antonio; Lieberman, Michael; Pochapin, Mark

    2014-03-24

    Obscure gastrointestinal bleeding is a common clinical scenario. In the upper gastrointestinal tract, gastric varices can be frequently overlooked on endoscopy, particularly if not suspected or volume depleted. We report a case of suspected gastrointestinal bleeding in a patient with a childhood history of pancreatitis, who also experienced severe epigastric pain while in hospital. After transfer to an academic medical centre, the presence of gastric varices was identified and presumed to be due to splenic vein thrombosis. Pancreatitis is the most common cause of splenic vein thrombosis and accords with the patient's history, even though it occurred many years previously. This case highlights the importance of recognising pancreatitis-induced splenic vein thrombosis as a possible aetiology for upper gastrointestinal bleeding.

  15. Gastroesophageal Variceal Bleeding as a Complication of Cystic Fibrosis in a 3-Month-Old Patient.

    PubMed

    Motamed, Farzaneh; Fallahi, Gholamhossein; Ahmadi, Faezeh; Bazvand, Fatemeh; Ahmadi, Maedeh; Eftekhari, Kambiz; Rezaei, Nima

    2016-03-01

    Cystic fibrosis (CF) is a hereditary disease of mucous and sweat glands, which affects the respiratory and gastrointestinal systems. Herein, we describe a 3-month-old girl with a history of recurrent episodes of urinary tract infections that required hospitalization. She was referred to our center at the age of three months, with massive gastroesophageal variceal bleeding. In physical examination, she had clubbing, hepatosplenomegaly, and mild ascites. Laboratory studies revealed high serum levels of liver enzymes and low level of Albumin. As of suspicious to CF, sweat tests were performed twice which confirmed the diagnosis of CF. Gastrointestinal bleeding due to gastroesophageal varices is a rare complication of CF, which could result as a consequence of hepatobiliary involvement of disease. Early diagnosis of CF could prevent severe complications and even death in this group of patients. PMID:27107529

  16. Plug-Assisted Retrograde Transvenous Obliteration for the Treatment of Gastric Variceal Hemorrhage

    PubMed Central

    Chang, Min-Yung; Kim, Taehwan; Shin, Wonseon; Shin, Minwoo; Kim, Gyoung Min; Won, Jong Yun; Park, Sung Il; Lee, Do Yun

    2016-01-01

    Objective To evaluate the feasibility, safety, and clinical outcomes of plug-assisted retrograde transvenous obliteration (PARTO) to treat gastric variceal hemorrhage in patients with portal hypertension. Materials and Methods From May 2012 to June 2014, 19 patients (11 men and 8 women, median age; 61, with history of gastric variceal hemorrhage; 17, active bleeding; 2) who underwent PARTO using a vascular plug and a gelfoam pledget were retrospectively analyzed. Clinical and laboratory data were examined to evaluate primary (technical and clinical success, complications) and secondary (worsening of esophageal varix [EV], change in liver function) end points. Median follow-up duration was 11 months, from 6.5 to 18 months. The Wilcoxon signed-rank test was used to compare laboratory data before and after the procedure. Results Technical success (complete occlusion of the efferent shunt and complete filling of gastric varix [GV] with a gelfoam slurry) was achieved in 18 of 19 (94.7%) patients. The embolic materials could not reach the GV in 1 patient who had endoscopic glue injection before our procedure. The clinical success rate (no recurrence of gastric variceal bleeding) was the same because the technically failed patient showed recurrent bleeding later. Acute complications included fever (n = 2), fever and hypotension (n = 2; one diagnosed adrenal insufficiency), and transient microscopic hematuria (n = 3). Ten patients underwent follow-up endoscopy; all exhibited GV improvement, except 2 without endoscopic change. Five patients exhibited aggravated EV, and 2 of them had a bleeding event. Laboratory findings were significantly improved after PARTO. Conclusion PARTO is technically feasible, safe, and effective for gastric variceal hemorrhage in patients with portal hypertension. PMID:26957908

  17. Sclerotherapy Of Esophageal Varices In Severe Hemophilia A Patient And High Titer Inhibitor--Case Report.

    PubMed

    Szczepanik, Andrzej B; Dąbrowski, Wojciech P; Szczepanik, Anna M; Pielaciński, Konrad; Jaśkowiak, Wojciech

    2015-09-01

    In cirrhotic hemophilia patients bleeding from esophageal varices is a serious clinical condition due to congenital deficiency of clotting factors VIII or IX, decreased prothrombin synthesis and hypersplenic thrombocytopenia. In hemophiliac with high-titer inhibitor bypassing therapy is required with activated prothrombin complex concentrates (aPCC) or recombinant activated coagulation factor VII (rFVIIa). Doses and duration treatment with these agents following endoscopic treatment of esophageal varices have not been yet established. Authors report the first case of a severe hemophilia A patient with high titer inhibitor (40 BU) treated with repeated injection sclerotherapy. The patient was admitted with symptoms of massive esophageal variceal hemorrhage ceased with emergency sclerotherapy. Bypassing therapy was administered with aPCC at initial dose of 72.5 U/kg and then with average daily dose of 162 U/kg through 5 days. To achieved a total eradication of esophageal varices the patient was then subjected to four elective sclerotherapy procedures. Two were covered by aPCC with daily dose of 120 U/kg and 145 U/kg for 4 and 3 days respectively and the following two procedures were covered by rFVIIa with the initial dose of 116 µg/kg and the next doses of 87 µg/kg administered every 3 hours in procedure day and every 4 hours on the next two days. During all procedures excellent hemostasis was achieved and no hemorrhagic or thromboembolic complications were observed. Bypassing regimen therapy with aPCC and rFVIIa we applied have been shown to be safe and effective in this patient subjected to sclerotherapy procedures.

  18. Abdominal varices mimicking an acute gastrointestinal hemorrhage during technetium-99m red blood cell scintigraphy

    SciTech Connect

    Moreno, A.J.; Byrd, B.F.; Berger, D.E.; Turnbull, G.L.

    1985-04-01

    Abdominal varices consisting of a caput medusae and dilated mesenteric veins resulted in pooling of Tc-99m tagged red blood cells (RBC) within these dilated vessels in a 57-year-old man with severe Laennec's cirrhosis. The atypical radiotracer localization within the abdomen mimicked an acute gastrointestinal hemorrhage. Clinical suspicion and careful evaluation of scintigraphic gastrointestinal bleeding studies will avoid false-positive interpretations.

  19. Intractable oesophageal variceal bleeding caused by splenic arteriovenous fistula: treatment by transcatheter arterial embolization

    PubMed Central

    Hung, C; Tseng, J; Lui, K; Wan, Y; Tsai, C; Shem, C; Wu, C

    1999-01-01

    We describe a rare case of splenic arteriovenous fistula and venous aneurysm which developed after splenectomy in a 40-year-old woman who presented with epigastralgia, watery diarrhoea, repeated haematemesis and melaena caused by hyperkinetic status of the portal system and bleeding of oesophageal varices. It was diagnosed by computed tomography and angiography, and obliterated with giant Gianturco steel coils.


Keywords: splenic arteriovenous fistula; gastrointestinal bleeding; transcatheter arterial embolization PMID:10435172

  20. Template-directed oligonucleotide ligation on hydroxylapatite

    NASA Technical Reports Server (NTRS)

    Acevedo, O. L.; Orgel, L. E.

    1986-01-01

    It has been suggested that the prebiotic synthesis of the precursors of biopolymers could have occurred on a solid surface such as that provided by clay or some other mineral. One such scheme envisages that growing polymers were localized by adsorption to a mineral surface where an activating agent or activated monomers were supplied continuously or cyclically. Here, it is reported that a sequence of reactions in which initially formed oligo(G)s are reactivated by conversion to phosphorimidazolides in the presence of poly(C) and then allowed to ligate is ideal, in that repeated cycles can be carried out on the surface of hydroxylapatite, whereas in the liquid phase the cycle could be achieved only with considerable difficulty.

  1. Sepsis Induced by Cecal Ligation and Puncture

    PubMed Central

    Wen, Haitao

    2014-01-01

    Summary Despite advances in intensive care unit interventions, including the use of specific antibiotics and anti-inflammation treatment, sepsis with concomitant multiple organ failure is the most common cause of death in many acute care units. In order to understand the mechanisms of clinical sepsis and develop effective therapeutic modalities, there is a need to use effective experimental models that faithfully replicate what occurs in patients with sepsis. Several models are commonly used to study sepsis, including intravenous endotoxin challenge, injection of live organisms into the peritoneal cavity, establishing abscesses in the extremities, and the induction of polymicrobial peritonitis via cecal ligation and puncture (CLP). Here, we describe the surgery procedure of CLP in mice, which has been proposed to closely replicate the nature and course of clinical sepsis in humans. PMID:23824895

  2. Ectopic Jejunal Variceal Rupture in a Liver Transplant Recipient Successfully Treated With Percutaneous Transhepatic Coil Embolization

    PubMed Central

    Abe, Satoru; Akamatsu, Nobuhisa; Hoshikawa, Mayumi; Shirata, Chikara; Sakamoto, Yoshihiro; Hasegawa, Kiyoshi; Kokudo, Norihiro

    2015-01-01

    Abstract Here we present the rupture of ectopic jejunal varices developing in a liver transplant recipient without portal hypertension, which was successfully treated with percutaneous transhepatic coil embolization. A 48-year-old man with massive melena was admitted to our department. He had undergone liver transplantation for hepatitis B virus-related liver cirrhosis 8 months before, and his postoperative course was satisfactory except for an acute cellular rejection. No evidence of bleeding was detected by upper endoscopy or colonoscopy, but dynamic multidetector computed tomography of the whole abdomen revealed an intestinal varix protruding into the lumen of the jejunum with suspected extravasation. There was no evidence of portal venous stenosis or thrombosis. Immediately upon diagnosis of the ruptured ectopic jejunal varix, percutaneous transhepatic coil embolization was performed, achieving complete hemostasis. The portal venous pressure measured during the procedure was within normal limits. He was discharged from the hospital 11 days after embolization and remained in stable condition without re-bleeding 6 months after discharge. This is the first report of an ectopic intestinal variceal rupture in an uneventful liver transplant recipient that was successfully treated with interventional percutaneous transhepatic coil embolization. Clinicians encountering liver transplant recipients with melena should be aware of the possibility of late-onset rupture of ectopic varices, even in those having an uneventful post-transplant course without portal hypertension. PMID:26632745

  3. Simultaneous combined balloon-occluded retrograde transvenous obliteration and partial splenic embolization for gastric fundal varices

    PubMed Central

    Osaki, Akihiko; Ikarashi, Shunzo; Ogawa, Masahiro; Kuraoka, Naosuke; Ogawa, Kohei; Sato, Munehiro; Aiba, Tsuneo; Yoneyama, Osamu; Furukawa, Koichi; Sugimura, Kazuhito; Igarashi, Kentarou

    2015-01-01

    Background We previously reported the techniques and usefulness of simultaneous combined balloon-occluded retrograde transvenous obliteration (B-RTO) and partial splenic embolization (PSE), based on the hypothesis that concomitant PSE can diminish the increase in portal venous pressure after B-RTO. Objective After experiencing more cases and performing longer-term follow-up, we re-evaluated the efficacy of simultaneous combined B-RTO and PSE for gastric fundal varices (GVs). Methods We performed B-RTO in 36 consecutive patients treated for GVs from 2005 to 2013. Twenty-three patients underwent simultaneous combined B-RTO and PSE (Group 1) and 13 underwent B-RTO monotherapy (Group 2). The outcomes were retrospectively evaluated. Results There were no significant differences in baseline characteristics between the two groups except that the splenic volumes were larger in Group 1 than 2. B-RTO was technically successful in 21 of 23 patients (91.3%) in Group 1 and in 12 of 13 patients (92.3%) in Group 2. In all patients with ruptured GVs (six in Group 1 and five in Group 2), complete hemostasis was obtained by B-RTO. Exacerbation of esophageal varices was significantly less frequent in Group 1 than 2 (p = 0.0017). Conclusion Concomitant PSE with B-RTO may contribute to prevention of the exacerbation of esophageal varices after B-RTO. PMID:26966524

  4. Efficacy of ankaferd blood stopper application on non-variceal upper gastrointestinal bleeding

    PubMed Central

    Gungor, Gokhan; Goktepe, M Hakan; Biyik, Murat; Polat, Ilker; Tuna, Tuncer; Ataseven, Huseyin; Demir, Ali

    2012-01-01

    AIM: To prospectively assess the hemostatic efficacy of the endoscopic topical use of ankaferd blood stopper (ABS) in active non-variceal upper gastrointestinal system (GIS) bleeding. METHODS: Endoscopy was performed on 220 patients under suspiciency of GIS bleeding. Patients with active non-variceal upper gastrointestinal bleeding (NVUGIB) with a spurting or oozing type were included. Firstly, 8-10 cc of isotonic saline was sprayed to bleeding lesions. Then, 8 cc of ABS was applied on lesions in which bleeding continued after isotonic saline application. The other endoscopic therapeutic methods were applied on the lesions in which the bleeding did not stop after ABS. RESULTS: Twenty-seven patients had an active NVUGIB with a spurting or oozing type and 193 patients were excluded from the study since they did not have non-variceal active bleeding. 8 cc of ABS was sprayed on to the lesions of 26 patients whose bleeding continued after isotonic saline and in 19 of them, bleeding stopped after ABS. Other endoscopic treatment methods were applied to the remaining patients and the bleeding was stopped with these interventions in 6 of 7 patients. CONCLUSION: ABS is an effective method on NVUGIB, particularly on young patients with no coagulopathy. ABS may be considered as part of a combination treatment with other endoscopic methods. PMID:23293725

  5. Enabling N-to-C Ser/Thr Ligation for Convergent Protein Synthesis via Combining Chemical Ligation Approaches.

    PubMed

    Lee, Chi Lung; Liu, Han; Wong, Clarence T T; Chow, Hoi Yee; Li, Xuechen

    2016-08-24

    In this article, Ser/Thr ligation(on/off) has been realized to enable N-to-C successive peptide ligations using a salicylaldehyde semicarbazone (SAL(off)) group by in situ activation with pyruvic acid of the peptide SAL(off) ester into the peptide salicylaldehyde (SAL(on)) ester. In addition, a peptide with a C-terminal thioester and N-terminal Ser or Thr as the middle peptide segment can undergo one-pot Ser/Thr ligation and native chemical ligation in the N-to-C direction. The utility of this combined ligation strategy in the N-to-C direction has been showcased through the convergent assembly of a human cytokine protein sequence, GlcNAcylated interleukin-25. PMID:27479006

  6. Efficient Ligation of the Schistosoma Hammerhead Ribozyme †

    PubMed Central

    Canny, Marella D.; Jucker, Fiona M.; Pardi, Arthur

    2011-01-01

    The hammerhead ribozyme from Schistosoma mansoni is the best characterized of the natural hammerhead ribozymes. Biophysical, biochemical, and structural studies have shown that the formation of the loop-loop tertiary interaction between stems I and II alters the global folding, cleavage kinetics, and conformation of the catalytic core of this hammerhead, leading to a ribozyme that is readily cleaved under physiological conditions. This study investigates the ligation kinetics and the internal equilibrium between cleavage and ligation for the Schistosoma hammerhead. Single turnover kinetic studies on a construct where the ribozyme cleaves and ligates substrate(s) in trans showed up to 23% ligation when starting from fully cleaved products. This was achieved by a ~2,000-fold increase in the rate of ligation compared to a minimal hammerhead without the loop-loop tertiary interaction, yielding an internal equilibrium that ranges from 2–3 at physiological Mg2+ ion concentrations (0.1 –1 mM). Thus, the natural Schistosoma hammerhead ribozyme is almost as efficient at ligation as it is at cleavage. The results here are consistent with a model where formation of the loop-loop tertiary interaction leads to a higher population of catalytically active molecules, and where formation of this tertiary interaction has a much larger effect on the ligation than the cleavage activity of the Schistosoma hammerhead ribozyme. PMID:17319693

  7. Convergent synthesis of proteins by kinetically controlled ligation

    DOEpatents

    Kent, Stephen; Pentelute, Brad; Bang, Duhee; Johnson, Erik; Durek, Thomas

    2010-03-09

    The present invention concerns methods and compositions for synthesizing a polypeptide using kinetically controlled reactions involving fragments of the polypeptide for a fully convergent process. In more specific embodiments, a ligation involves reacting a first peptide having a protected cysteyl group at its N-terminal and a phenylthioester at its C-terminal with a second peptide having a cysteine residue at its N-termini and a thioester at its C-termini to form a ligation product. Subsequent reactions may involve deprotecting the cysteyl group of the resulting ligation product and/or converting the thioester into a thiophenylester.

  8. Balloon-Occluded Antegrade Transvenous Sclerotherapy to Treat Rectal Varices: A Direct Puncture Approach to the Superior Rectal Vein Through the Greater Sciatic Foramen Under CT Fluoroscopy Guidance

    SciTech Connect

    Ono, Yasuyuki Kariya, Shuji Nakatani, Miyuki Yoshida, Rie Kono, Yumiko Kan, Naoki Ueno, Yutaka Komemushi, Atsushi Tanigawa, Noboru

    2015-10-15

    Rectal varices occur in 44.5 % of patients with ectopic varices caused by portal hypertension, and 48.6 % of these patients are untreated and followed by observation. However, bleeding occurs in 38 % and shock leading to death in 5 % of such patients. Two patients, an 80-year-old woman undergoing treatment for primary biliary cirrhosis (Child-Pugh class A) and a 63-year-old man with class C hepatic cirrhosis (Child-Pugh class A), in whom balloon-occluded antegrade transvenous sclerotherapy was performed to treat rectal varices are reported. A catheter was inserted by directly puncturing the rectal vein percutaneously through the greater sciatic foramen under computed tomographic fluoroscopy guidance. In both cases, the rectal varices were successfully treated without any significant complications, with no bleeding from rectal varices after embolization.

  9. Formatting and ligating biopolymers using adjustable nanoconfinement

    NASA Astrophysics Data System (ADS)

    Berard, Daniel J.; Shayegan, Marjan; Michaud, Francois; Henkin, Gil; Scott, Shane; Leslie, Sabrina

    2016-07-01

    Sensitive visualization and conformational control of long, delicate biopolymers present critical challenges to emerging biotechnologies and biophysical studies. Next-generation nanofluidic manipulation platforms strive to maintain the structural integrity of genomic DNA prior to analysis but can face challenges in device clogging, molecular breakage, and single-label detection. We address these challenges by integrating the Convex Lens-induced Confinement (CLiC) technique with a suite of nanotopographies embedded within thin-glass nanofluidic chambers. We gently load DNA polymers into open-face nanogrooves in linear, concentric circular, and ring array formats and perform imaging with single-fluorophore sensitivity. We use ring-shaped nanogrooves to access and visualize confinement-enhanced self-ligation of long DNA polymers. We use concentric circular nanogrooves to enable hour-long observations of polymers at constant confinement in a geometry which eliminates the confinement gradient which causes drift and can alter molecular conformations and interactions. Taken together, this work opens doors to myriad biophysical studies and biotechnologies which operate on the nanoscale.

  10. A Photo-Triggered Traceless Staudinger-Bertozzi Ligation Reaction.

    PubMed

    Hu, Peng; Feng, Tianshi; Yeung, Chi-Chung; Koo, Chi-Kin; Lau, Kai-Chung; Lam, Michael H W

    2016-08-01

    The use of light to control the course of a chemical/biochemical reaction is an attractive idea because of its ease of administration with high precision and fine spatial resolution. Staudinger ligation is one of the commonly adopted conjugation processes that involve a spontaneous reaction between azides and arylphosphines to form iminophosphoranes, which further hydrolyze to give stable amides. We designed an anthracenylmethyl diphenylphosphinothioester (1) that showed promising Staudinger ligation reactivity upon photo-excitation. Broadband photolysis at 360-400 nm in aqueous organic solvents induced heterolytic cleavage of its anthracenylmethyl-phosphorus bond, releasing a diphenylphosphinothioester (2) as an efficient traceless Staudinger-Bertozzi ligation reagent. The quantum yield of such a photo-induced heterolytic bond-cleavage at the optimal wavelength of photolysis (376 nm) at room temperature is ≥0.07. This work demonstrated the feasibility of photocaging arylphosphines to realize the photo-triggering of the Staudinger ligation reaction.

  11. Cross-ligation and exchange reactions catalyzed by hairpin ribozymes.

    PubMed Central

    Komatsu, Y; Koizumi, M; Sekiguchi, A; Ohtsuka, E

    1993-01-01

    The negative strand of the satellite RNA of tobacco ringspot virus (sTobRV(-)) contains a hairpin catalytic domain that shows self-cleavage and self-ligation activities in the presence of magnesium ions. We describe here that the minimal catalytic domain can catalyze a cross-ligation reaction between two kinds of substrates in trans. The cross-ligated product increased when the reaction temperature was decreased during the reaction from 37 degrees C to 4 degrees C. A two-stranded hairpin ribozyme, divided into two fragments between G45 and U46 in a hairpin loop, showed higher ligation activity than the nondivided ribozyme. The two stranded ribozyme also catalyzed an exchange reaction of the 3'-portion of the cleavage site. Images PMID:8441626

  12. Protein chemical synthesis by serine and threonine ligation

    PubMed Central

    Zhang, Yinfeng; Lam, Hiu Yung; Lee, Chi Lung; Li, Xuechen

    2013-01-01

    An efficient method has been developed for the salicylaldehyde ester-mediated ligation of unprotected peptides at serine (Ser) or threonine (Thr) residues. The utility of this peptide ligation approach has been demonstrated through the convergent syntheses of two therapeutic peptides––ovine-corticoliberin and Forteo––and the human erythrocyte acylphosphatase protein (∼11 kDa). The requisite peptide salicylaldehyde ester precursor is prepared in an epimerization-free manner via Fmoc–solid-phase peptide synthesis. PMID:23569249

  13. Rubber band ligation of hemorrhoids: A guide for complications

    PubMed Central

    Albuquerque, Andreia

    2016-01-01

    Rubber band ligation is one of the most important, cost-effective and commonly used treatments for internal hemorrhoids. Different technical approaches were developed mainly to improve efficacy and safety. The technique can be employed using an endoscope with forward-view or retroflexion or without an endoscope, using a suction elastic band ligator or a forceps ligator. Single or multiple ligations can be performed in a single session. Local anaesthetic after ligation can also be used to reduce the post-procedure pain. Mild bleeding, pain, vaso-vagal symptoms, slippage of bands, priapism, difficulty in urination, anal fissure, and chronic longitudinal ulcers are normally considered minor complications, more frequently encountered. Massive bleeding, thrombosed hemorrhoids, severe pain, urinary retention needing catheterization, pelvic sepsis and death are uncommon major complications. Mild pain after rubber band ligation is the most common complication with a high frequency in some studies. Secondary bleeding normally occurs 10 to 14 d after banding and patients taking anti-platelet and/or anti-coagulant medication have a higher risk, with some reports of massive life-threatening haemorrhage. Several infectious complications have also been reported including pelvic sepsis, Fournier’s gangrene, liver abscesses, tetanus and bacterial endocarditis. To date, seven deaths due to these infectious complications were described. Early recognition and immediate treatment of complications are fundamental for a favourable prognosis. PMID:27721924

  14. Covalent ligation studies on the human telomere quadruplex

    PubMed Central

    Qi, Jianying; Shafer, Richard H.

    2005-01-01

    Recent X-ray crystallographic studies on the human telomere sequence d[AGGG(TTAGGG)3] revealed a unimolecular, parallel quadruplex structure in the presence of potassium ions, while earlier NMR results in the presence of sodium ions indicated a unimolecular, antiparallel quadruplex. In an effort to identify and isolate the parallel form in solution, we have successfully ligated into circular products the single-stranded human telomere and several modified human telomere sequences in potassium-containing solutions. Using these sequences with one or two terminal phosphates, we have made chemically ligated products via creation of an additional loop. Circular products have been identified by polyacrylamide gel electrophoresis, enzymatic digestion with exonuclease VII and electrospray mass spectrometry in negative ion mode. Optimum pH for the ligation reaction of the human telomere sequence ranges from 4.5 to 6.0. Several buffers were also examined, with MES yielding the greatest ligation efficiency. Human telomere sequences with two phosphate groups, one each at the 3′ and 5′ ends, were more efficient at ligation, via pyrophosphate bond formation, than the corresponding sequences with only one phosphate group, at the 5′ end. Circular dichroism spectra showed that the ligation product was derived from an antiparallel, single-stranded guanine quadruplex rather than a parallel single-stranded guanine quadruplex structure. PMID:15933211

  15. Rapamycin delays salivary gland atrophy following ductal ligation.

    PubMed

    Bozorgi, S S; Proctor, G B; Carpenter, G H

    2014-03-27

    Salivary gland atrophy is a frequent consequence of head and neck cancer irradiation therapy but can potentially be regulated through the mammalian target of rapamycin (mTOR). Excretory duct ligation of the mouse submandibular gland provokes severe glandular atrophy causing activation of mTOR. This study aims to discover the effects of blocking mTOR signaling in ligation-induced atrophic salivary glands. Following 1 week of unilateral submandibular excretory duct ligation: gland weights were significantly reduced, 4E-BP1 and S6rp were activated, and tissue morphology revealed typical signs of atrophy. However, 3 days following ligation with rapamycin treatment, a selective mTOR inhibitor, gland weights were maintained, 4E-BP1 and S6rp phosphorylation was inhibited, and there were morphological signs of recovery from atrophy. However, following 5 and 7 days of ligation and rapamycin treatment, glands expressed active mTOR and showed signs of considerable atrophy. This evidence suggests that inhibition of mTOR by rapamycin delays ligation-induced atrophy of salivary glands.

  16. Vessel Ligation Training via an Adaptive Simulation Curriculum

    PubMed Central

    Hu, Yinin; Goodrich, Robyn N.; Le, Ivy A.; Brooks, Kendall D.; Sawyer, Robert G.; Smith, Philip W.; Schroen, Anneke T.; Rasmussen, Sara K.

    2015-01-01

    Background A cost-effective model for open vessel ligation is currently lacking. We hypothesized that a novel, inexpensive vessel ligation simulator can efficiently impart transferrable surgical skills to novice trainees. Materials and Methods VesselBox was designed to simulate vessel ligation using surgical gloves as surrogate vessels. Fourth-year medical students performed ligations using VesselBox, and were evaluated by surgical faculty using the Objective Structured Assessments of Technical Skills (OSATS) global rating scale and a task-specific checklist. Subsequently, each student was trained using VesselBox in an adaptive practice session guided by cumulative sum. Post-testing was performed on fresh human cadavers by evaluators blinded to pre-test results. Results Sixteen students completed the study. VesselBox practice sessions averaged 21.8 minutes per participant (IQR 19.5 – 27.7). Blinded post-tests demonstrated increased proficiency, as measured by both OSATS (3.23 vs 2.29, p < 0.001) and checklist metrics (7.33 vs 4.83, p < 0.001). Median speed improved from 128.2 seconds to 97.5 seconds per vessel ligated (p = 0.001). Following this adaptive training protocol, practice volume was not associated with post-test performance. Conclusions VesselBox is a cost-effective, low-fidelity vessel ligation model suitable for graduating medical students and junior residents. Cumulative sum can facilitate an adaptive, individualized curriculum for simulation training. PMID:25796112

  17. Intramyocardial activation in early ventricular arrhythmias following coronary artery ligation.

    PubMed

    Kaplinsky, E; Ogawa, S; Kmetzo, J; Balke, C W; Dreifus, L S

    1980-01-01

    Subendocardial, subepicardial and intramyocardial activation in the ischemic zone was investigated in 20 anesthetized open chest dogs 0-30 minutes after the ligation of the left anterior descending coronary artery. Single and composite electrograms and lead 2 of the ECG were recorded. Coronary artery ligation produced marked delay, fragmentation, and reduction in amplitude in the electrical activity of the subepicardial and intramyocardial muscle layers. The activation remained synchronous in the subendocardial muscle layers. Extension of electrical activity in the ischemic subepicardium and intramyocardium beyond the T wave of the surface ECG preceded the onset of immediate ventricular arrhythmias (IVA) during the initial ten minute period after coronary artery ligation. However, a second surge of delayed ventricular arrhythmias (DVA), 10-30 minutes after ligation, was not associated with the appearance of diastolic electrical activity in any of the subepicardial or myocardial layers. It appears that subepicardial as well as intramyocardial reentry could play an important role in the genesis of the immediate ventricular arrhythmias (1-10 minutes after ligation). In contrast, no obvious reentrant activity as evidenced by delayed and fragmented electrical activity could be observed in the electrogram from any of the myocardial electrical activity could be observed in the electrogram from any of the myocardial layers with the appearance of delayed ventricular ectopic activity 10-30 minutes after ligation.

  18. Ligation with nucleic acid sequence-based amplification.

    PubMed

    Ong, Carmichael; Tai, Warren; Sarma, Aartik; Opal, Steven M; Artenstein, Andrew W; Tripathi, Anubhav

    2012-01-01

    This work presents a novel method for detecting nucleic acid targets using a ligation step along with an isothermal, exponential amplification step. We use an engineered ssDNA with two variable regions on the ends, allowing us to design the probe for optimal reaction kinetics and primer binding. This two-part probe is ligated by T4 DNA Ligase only when both parts bind adjacently to the target. The assay demonstrates that the expected 72-nt RNA product appears only when the synthetic target, T4 ligase, and both probe fragments are present during the ligation step. An extraneous 38-nt RNA product also appears due to linear amplification of unligated probe (P3), but its presence does not cause a false-positive result. In addition, 40 mmol/L KCl in the final amplification mix was found to be optimal. It was also found that increasing P5 in excess of P3 helped with ligation and reduced the extraneous 38-nt RNA product. The assay was also tested with a single nucleotide polymorphism target, changing one base at the ligation site. The assay was able to yield a negative signal despite only a single-base change. Finally, using P3 and P5 with longer binding sites results in increased overall sensitivity of the reaction, showing that increasing ligation efficiency can improve the assay overall. We believe that this method can be used effectively for a number of diagnostic assays. PMID:22449695

  19. Isolated Gastric Varices and Use of Balloon-occlusive Retrograde Transvenous Obliteration: A Case Report and Literature Review.

    PubMed

    McCarty, Thomas R; Bakhit, Mena; Rustagi, Tarun

    2016-03-01

    Isolated gastric varices are far less prevalent in Western countries where the rate of splenic thrombosis is much lower. However, in Asian countries the entity is more common and therefore a more robust treatment approach has been developed. Balloon-occlusive retrograde transvenous obliteration (BRTO) was first described in 1984 and then revived in 1996. The procedure, while uncommon in the U.S. and not recognized by the AASLD practice guidelines, allows for direct exclusion from the portosystemic system. Here we describe the case of a patient with alcoholic cirrhosis decompensated by bleeding gastric varices treated with BRTO.

  20. Isolated Gastric Varices and Use of Balloon-occlusive Retrograde Transvenous Obliteration: A Case Report and Literature Review.

    PubMed

    McCarty, Thomas R; Bakhit, Mena; Rustagi, Tarun

    2016-03-01

    Isolated gastric varices are far less prevalent in Western countries where the rate of splenic thrombosis is much lower. However, in Asian countries the entity is more common and therefore a more robust treatment approach has been developed. Balloon-occlusive retrograde transvenous obliteration (BRTO) was first described in 1984 and then revived in 1996. The procedure, while uncommon in the U.S. and not recognized by the AASLD practice guidelines, allows for direct exclusion from the portosystemic system. Here we describe the case of a patient with alcoholic cirrhosis decompensated by bleeding gastric varices treated with BRTO. PMID:27014763

  1. Esophageal Stent for Refractory Variceal Bleeding: A Systemic Review and Meta-Analysis

    PubMed Central

    Guo, Xiao-Zhong

    2016-01-01

    Background. Preliminary studies suggest that covered self-expandable metal stents may be helpful in controlling esophageal variceal bleeding. Aims. To evaluate the effectiveness and safety of esophageal stent in refractory variceal bleeding in a systematic review and meta-analysis. Methods. A comprehensive literature search was conducted on PubMed, EMBASE, and Cochrane Library covering the period from January 1970 to December 2015. Data were selected and abstracted from eligible studies and were pooled using a random-effects model. Heterogeneity was assessed using I2 test. Results. Five studies involving 80 patients were included in the analysis. The age of patients ranged from 18 to 91 years. The mean duration of follow-up was 46.8 d (range, 30–60 d). The success rate of stent deployment was 96.7% (95% CI: 91.6%–99.5%) and complete response to esophageal stenting was in 93.9% (95% CI: 82.2%–99.6%). The incidence of rebleeding was 13.2% (95% CI: 1.8%–32.8%) and the overall mortality was 34.5% (95% CI: 24.8%–44.8%). Most of patients (87.4%) died from hepatic or multiple organ failure, and only 12.6% of patients died from uncontrolled bleeding. There was no stent-related complication reported and the incidence of stent migration was 21.6% (95% CI: 4.7%–46.1%). Conclusion. Esophageal stent may be considered in patients with variceal bleeding refractory to conventional therapy. PMID:27517043

  2. Adrenal pseudomasses due to varices: angiographic-CT-MRI-pathologic correlations

    SciTech Connect

    Brady, T.M.; Gross, B.H.; Glazer, G.M. Williams, D.M.

    1985-08-01

    Periadrenal and adrenal portosystemic collaterals are a recently reported cause of adrenal pseudotumor on computed tomography (CT). Nine patients with this left adrenal pseudotumor illustrate its typical position and appearance on CT, angiography, CT-angiography, and magnetic resonance imaging (MRI). The anatomic basis for variceal adrenal pseudotumors is the left inferior phrenic vein, which passes immediately anterior to the left adrenal gland and which serves as a collateral pathway from splenic to left renal vein in portal hypertension. Thus, unlike previously described adrenal pseudotumors, these venous collaterals are not anatomically distinguishable from the adrenal gland on CT. Bolus dynamic CT is usually diagnostic, but in equivocal cases, MRI may prove useful.

  3. Association of Oesophageal Varices and Splanchnic Vein Thromboses in Patients with JAK2-Positive Myeloproliferative Neoplasms: Presentation of Two Cases and Data from a Retrospective Analysis

    PubMed Central

    Link, Cornelia S.; Platzbecker, Uwe; Kroschinsky, Frank; Pannach, Sven; Thiede, Christian; Platzek, Ivan; Ehninger, Gerhard; Schuler, Markus K.

    2013-01-01

    Background Oesophageal varices and gastrointestinal bleeding are common complications of liver cirrhosis. More rarely, oesophageal varices occur in patients with non-cirrhotic portal hypertension that results from thromboses of portal or splanchnic veins. Case Report We describe 2 young men who initially presented with varices as a result of portal vein thromboses. In the clinical follow-up, both were tested positive for a JAK2 mutation and consequently diagnosed with myeloproliferative neoplasms (MPNs). In an attempt to characterise the frequency of gastrointestinal complications in patients with JAK2-positive MPNs, we retrospectively analysed all known affected patients from our clinic for the diagnosis of portal vein thromboses and oesophageal varices. Strikingly, 48% of those who had received an oesophagogastroduodenoscopy had detectable oesophageal or gastric varices, and 82% of those suffered from portal or splanchnic vein thromboses. Conclusion While the association between JAK2, myeloproliferative disease and thrombotic events is well established, patients with idiopathic oesophageal varices are not regularly tested for JAK2 mutations. However, the occurrence of oesophageal varices may be the first presenting symptom of a MPN with a JAK2 mutation, and affected patients may profit from a close haematological monitoring to assure the early detection of developing MPN. PMID:23898274

  4. A rare case of splenic lymphoma in a patient with polymyositis manifesting as gastric variceal bleeding.

    PubMed

    Parekh, Ravish; Walia, Sandeep; Zalawadia, Ashish; Siddiqui, Yousuf

    2015-04-01

    We report an unusual case of upper gastrointestinal bleeding due to isolated gastric variceal bleeding in a patient with splenomegaly who was subsequently diagnosed with diffuse large B-cell lymphoma. The patient is a 47-year-old male with a history of polymyositis who presented to the emergency room with complaints of lightheadedness and melena for 2 days. On initial presentation, the patient had positive orthostatic vital signs. He was found to be anemic with presenting hemoglobin of 5.8 g/dl (compared with 13.4 g/dl 4 months prior to presentation). The patient was aggressively resuscitated with intravenous fluid and blood transfusions. An emergency esophagogastroduodenoscopy was performed which showed isolated gastric varices in the fundus of the stomach, with no active bleeding or high-risk stigmata. Abdominal computed tomography revealed focal splenic vein thrombosis and splenomegaly with ill-defined hypodensities. Portal and superior mesenteric veins were patent. Mild edema was seen surrounding the spleen and non-specific abdominal lymphadenopathy was also reported. A surgical consultation recommended an urgent splenectomy. Pathology of the removed spleen revealed diffuse large B-cell lymphoma. Positron emission tomography-computed tomography revealed lymphomatous disease in the thorax, abdomen, pelvis and bone marrow. The patient was subsequently started on chemotherapy.

  5. Role of self-expanding metal stents in the management of variceal haemorrhage: Hype or hope?

    PubMed Central

    Hogan, Brian J; O’Beirne, James P

    2016-01-01

    Despite the advances of medical, endoscopic and radiological therapy over recent years the mortality rates of acute variceal haemorrhage are still 16%-20% and the medium term outcome has not improved in the last 25 years. Early transjugular intrahepatic portosystemic shunt has proved to be an effective therapy for selected groups of patients with a high risk of re-bleeding and moderate liver disease. However, there is an unmet need for a therapy that can be applied in patients with a high risk of re-bleeding and advanced liver disease either as definitive therapy or as a bridge to permanent therapy. Self-expanding metal stents can be placed without the need for endoscopic or fluoroscopic control and, once in place, will provide effective haemostasis and allow a route for oral fluids and nutrition. They can remain in place whilst liver function recovers and secondary prophylaxis is initiated. We review the results of 6 case series including a total of 83 patients and the first randomised controlled trial of self-expanding metal stents vs balloon tamponade (BT) in the management of refractory variceal haemorrhage. We report that self-expanding metal stents provide effective haemostasis and perform better than BT in refractory bleeding, where they are associated with fewer complications. Whilst the most effective place for self-expanding metal stents in the management algorithm needs to be determined by further randomised controlled trials, currently they provide an effective alternative to BT in selected patients. PMID:26788260

  6. Downhill varices secondary to HeRO graft-related SVC syndrome.

    PubMed

    Pillai, Unnikrishnan; Roopkiranjot, Kahlon; Lakshminarayan, Nandagopal; Balabhadrapatruni, Krishna; Gebregeorgis, Wihib; Kissner, Paul

    2013-01-01

    Tunneled hemodialysis catheters are well-documented causes of benign central vein stenosis, which can be associated with proximal or downhill esophageal varices due to shunting of blood flow from the upper portion of the body through the esophageal venous plexuses. A majority of these cases remain asymptomatic. As a result, studies are largely limited to symptomatic patients, with incidence rates ranging from 16% to 29%. Recently, Hemodialysis Reliable Outflow (HeRO) graft has been introduced as an effective alternate hemodialysis access in catheter-dependent patients, especially in the presence of significant central venous occlusion. It differs from a conventional arteriovenous graft (AVG) by the fact that its venous outflow end is in the right atrium via one of the central veins, bypassing any significant occlusion upstream. Lower intervention rates and reduced incidence of bacteremia make it comparable to conventional tunneled catheters. However, the incidence of central vein occlusion and associated complications with HeRO grafts is unknown. We present the first case of gastrointestinal bleeding from downhill esophageal varices secondary to HeRO-graft-related SVC occlusion.

  7. Role of self-expanding metal stents in the management of variceal haemorrhage: Hype or hope?

    PubMed

    Hogan, Brian J; O'Beirne, James P

    2016-01-10

    Despite the advances of medical, endoscopic and radiological therapy over recent years the mortality rates of acute variceal haemorrhage are still 16%-20% and the medium term outcome has not improved in the last 25 years. Early transjugular intrahepatic portosystemic shunt has proved to be an effective therapy for selected groups of patients with a high risk of re-bleeding and moderate liver disease. However, there is an unmet need for a therapy that can be applied in patients with a high risk of re-bleeding and advanced liver disease either as definitive therapy or as a bridge to permanent therapy. Self-expanding metal stents can be placed without the need for endoscopic or fluoroscopic control and, once in place, will provide effective haemostasis and allow a route for oral fluids and nutrition. They can remain in place whilst liver function recovers and secondary prophylaxis is initiated. We review the results of 6 case series including a total of 83 patients and the first randomised controlled trial of self-expanding metal stents vs balloon tamponade (BT) in the management of refractory variceal haemorrhage. We report that self-expanding metal stents provide effective haemostasis and perform better than BT in refractory bleeding, where they are associated with fewer complications. Whilst the most effective place for self-expanding metal stents in the management algorithm needs to be determined by further randomised controlled trials, currently they provide an effective alternative to BT in selected patients.

  8. Collateral Capillary Arterialization following arteriolar ligation in murine skeletal muscle

    PubMed Central

    Mac Gabhann, Feilim; Peirce, Shayn M.

    2010-01-01

    OBJECTIVE Chronic and acute ischemic diseases – peripheral artery disease, coronary artery disease, stroke – result in tissue damage unless blood flow is maintained or restored in a timely manner. Mice of different strains recover from arteriolar ligation (by increasing collateral blood flow) at different speeds. We quantify the spatio-termporal patterns of microvascular network remodeling following arteriolar ligation in different mouse strains to better understand interindividual variability. METHODS Whole-muscle spinotrapezius microvascular networks of mouse strains C57Bl/6, Balb/c and CD1 were imaged using confocal microscopy following ligation of feeding arterioles. RESULTS Baseline arteriolar structures of C57Bl/6 and Balb/c mice feature heavily ramified arcades and unconnected dendritic trees, respectively. This network angioarchitecture identifies ischemia-protected and ischemia-vulnerable tissues: unlike C57Bl/6, downstream capillary perfusion in Balb/c spinotrapezius is lost following ligation. Perfusion recovery requires arterialization (expansion and investment of mural cells) of a subset of capillaries forming a new low-resistance collateral pathway between arteriolar trees. Outbred CD1 exhibit either Balb/c-like or C57Bl/6-like spinotrapezius angioarchitecture, predictive of response to arteriolar ligation. CONCLUSIONS This collateral capillary arterialization process may explain the reported longer time required for blood flow recovery in Balb/c hindlimb ischemia, as low-resistance blood flow pathways along capillary conduits must be formed (‘arterialization’) before reperfusion. PMID:20618691

  9. Oxidative Deselenization of Selenocysteine: Applications for Programmed Ligation at Serine.

    PubMed

    Malins, Lara R; Mitchell, Nicholas J; McGowan, Sheena; Payne, Richard J

    2015-10-19

    Despite the unique chemical properties of selenocysteine (Sec), ligation at Sec is an under-utilized methodology for protein synthesis. We describe herein an unprecedented protocol for the conversion of Sec to serine (Ser) in a single, high-yielding step. When coupled with ligation at Sec, this transformation provides a new approach to programmed ligations at Ser residues. This new reaction is compatible with a wide range of functionality, including the presence of unprotected amino acid side chains and appended glycans. The utility of the methodology is demonstrated in the rapid synthesis of complex glycopeptide fragments of the epithelial glycoproteins MUC5AC and MUC4 and through the total synthesis of the structured, cysteine (Cys)-free protein eglin C. PMID:26384718

  10. RNA-Catalyzed RNA Ligation on an External RNA Template

    NASA Technical Reports Server (NTRS)

    McGinness, Kathleen E.; Joyce, Gerald F.

    2002-01-01

    Variants of the hc ligase ribozyme, which catalyzes ligation of the 3' end of an RNA substrate to the 5' end of the ribozyme, were utilized to evolve a ribozyme that catalyzes ligation reactions on an external RNA template. The evolved ribozyme catalyzes the joining of an oligonucleotide 3'-hydroxyl to the 5'-triphosphate of an RNA hairpin molecule. The ribozyme can also utilize various substrate sequences, demonstrating a largely sequence-independent mechanism for substrate recognition. The ribozyme also carries out the ligation of two oligonucleotides that are bound at adjacent positions on a complementary template. Finally, it catalyzes addition of mononucleoside '5-triphosphates onto the '3 end of an oligonucleotide primer in a template-dependent manner. The development of ribozymes that catalyze polymerase-type reactions contributes to the notion that an RNA world could have existed during the early history of life on Earth.

  11. The Staudinger ligation-a gift to chemical biology.

    PubMed

    Köhn, Maja; Breinbauer, Rolf

    2004-06-14

    Although the reaction between an azide and a phosphane to form an aza-ylide was discovered by Hermann Staudinger more than 80 years ago and has found widespread application in organic synthesis, its potential as a highly chemoselective ligation method for the preparation of bioconjugates has been recognized only recently. As the two reaction partners are bioorthogonal to almost all functionalities that exist in biological systems and react at room temperature in an aqueous environment, the Staudinger ligation has even found application in the complex environment of living cells. Herein we describe the current state of knowledge on this reaction and its application both for the preparation of bioconjugates and as a ligation method in chemical biology.

  12. Template-Directed Ligation of Peptides to Oligonucleotides

    NASA Technical Reports Server (NTRS)

    Bruick, Richard K.; Dawson, Philip E.; Kent, Stephen BH; Usman, Nassim; Joyce, Gerald F.

    1996-01-01

    Synthetic oligonucleotides and peptides have enjoyed a wide range of applications in both biology and chemistry. As a consequence, oligonucleotide-peptide conjugates have received considerable attention, most notably in the development of antisense constructs with improved pharmacological properties. In addition, oligonucleotide-peptide conjugates have been used as molecular tags, in the assembly of supramolecular arrays and in the construction of encoded combinatorial libraries. To make these chimeric molecules more accessible for a broad range of investigations, we sought to develop a facile method for joining fully deprotected oligonucleotides and peptides through a stable amide bond linkage. Furthermore, we wished to make this ligation reaction addressable, enabling one to direct the ligation of specific oligonucleotide and peptide components.To confer specificity and accelerate the rate of the reaction, the ligation process was designed to be dependent on the presence of a complementary oligonucleotide template.

  13. A Generic Polymer-Protein Ligation Strategy for Vaccine Delivery.

    PubMed

    Lybaert, Lien; Vanparijs, Nane; Fierens, Kaat; Schuijs, Martijn; Nuhn, Lutz; Lambrecht, Bart N; De Geest, Bruno G

    2016-03-14

    Although the field of cancer immunotherapy is intensively investigated, there is still a need for generic strategies that allow easy, mild and efficient formulation of vaccine antigens. Here we report on a generic polymer-protein ligation strategy to formulate protein antigens into reversible polymeric conjugates for enhanced uptake by dendritic cells and presentation to CD8 T-cells. A N-hydroxypropylmethacrylamide (HPMA)-based copolymer was synthesized via RAFT polymerization followed by introduction of pyridyldisulfide moieties. To enhance ligation efficiency to ovalbumin, which is used as a model protein antigen, protected thiols were introduced onto lysine residues and deprotected in situ in the presence of the polymer. The ligation efficiency was compared for both the thiol-modified versus unmodified ovalbumin, and the reversibility was confirmed. Furthermore, the obtained nanoconjugates were tested in vitro for their interaction and association with dendritic cells, showing enhanced cellular uptake and antigen cross-presentation to CD8 T-cells.

  14. High-throughput determination of RNA structure by proximity ligation.

    PubMed

    Ramani, Vijay; Qiu, Ruolan; Shendure, Jay

    2015-09-01

    We present an unbiased method to globally resolve RNA structures through pairwise contact measurements between interacting regions. RNA proximity ligation (RPL) uses proximity ligation of native RNA followed by deep sequencing to yield chimeric reads with ligation junctions in the vicinity of structurally proximate bases. We apply RPL in both baker's yeast (Saccharomyces cerevisiae) and human cells and generate contact probability maps for ribosomal and other abundant RNAs, including yeast snoRNAs, the RNA subunit of the signal recognition particle and the yeast U2 spliceosomal RNA homolog. RPL measurements correlate with established secondary structures for these RNA molecules, including stem-loop structures and long-range pseudoknots. We anticipate that RPL will complement the current repertoire of computational and experimental approaches in enabling the high-throughput determination of secondary and tertiary RNA structures. PMID:26237516

  15. Development of an Improved Animal Model of Overactive Bladder: Transperineal Ligation versus Transperitoneal Ligation in Male Rats

    PubMed Central

    Kim, Woo Hyun; Bae, Woong Jin; Park, Jung Woo; Choi, Jin Bong; Kim, Su Jin; Cho, Hyuk Jin; Ha, U Syn; Hong, Sung Hoo; Lee, Ji Youl; Hwang, Sung Yeoun

    2016-01-01

    Purpose We compared a transperineal ligation model and a transperitoneal ligation model in male rats to determine which animal model of overactive bladder (OAB) was more useful based on cystometrography, estimations of oxidative stress, and measurements of pro-inflammatory cytokine levels. Materials and Methods Male rats were randomly divided into three groups (n=15 in each): the control group, the transperineal ligation group, and the transperitoneal ligation group. Four weeks after the ligation procedure, cystometrography was performed and oxidative stress, pro-inflammatory cytokine levels, and histologic changes were evaluated. Oxidative stress was assessed by measuring 8-hydroxy-20-deoxyguanosine and superoxide dismutase, and pro-inflammatory cytokine activity was investigated by measuring levels of interleukin (IL)-6, IL-8, and tumor necrosis factor-α. Results The transperineal model led to results similar to those observed for the transperitoneal model, namely (1) increased voiding frequency and reductions in the non-voiding contraction interval and the maximal vesical pressure, (2) increased levels of oxidative stress markers, (3) increased pro-inflammatory cytokine levels, and (4) fibrotic changes in the bladder tissue. Conclusions We suggest that the transperineal procedure can be used as an alternative OAB model in male rats. PMID:27574597

  16. Alternative Okazaki Fragment Ligation Pathway by DNA Ligase III.

    PubMed

    Arakawa, Hiroshi; Iliakis, George

    2015-01-01

    Higher eukaryotes have three types of DNA ligases: DNA ligase 1 (Lig1), DNA ligase 3 (Lig3) and DNA ligase 4 (Lig4). While Lig1 and Lig4 are present in all eukaryotes from yeast to human, Lig3 appears sporadically in evolution and is uniformly present only in vertebrates. In the classical, textbook view, Lig1 catalyzes Okazaki-fragment ligation at the DNA replication fork and the ligation steps of long-patch base-excision repair (BER), homologous recombination repair (HRR) and nucleotide excision repair (NER). Lig4 is responsible for DNA ligation at DNA double strand breaks (DSBs) by the classical, DNA-PKcs-dependent pathway of non-homologous end joining (C-NHEJ). Lig3 is implicated in a short-patch base excision repair (BER) pathway, in single strand break repair in the nucleus, and in all ligation requirements of the DNA metabolism in mitochondria. In this scenario, Lig1 and Lig4 feature as the major DNA ligases serving the most essential ligation needs of the cell, while Lig3 serves in the cell nucleus only minor repair roles. Notably, recent systematic studies in the chicken B cell line, DT40, involving constitutive and conditional knockouts of all three DNA ligases individually, as well as of combinations thereof, demonstrate that the current view must be revised. Results demonstrate that Lig1 deficient cells proliferate efficiently. Even Lig1/Lig4 double knockout cells show long-term viability and proliferate actively, demonstrating that, at least in DT40, Lig3 can perform all ligation reactions of the cellular DNA metabolism as sole DNA ligase. Indeed, in the absence of Lig1, Lig3 can efficiently support semi-conservative DNA replication via an alternative Okazaki-fragment ligation pathway. In addition, Lig3 can back up NHEJ in the absence of Lig4, and can support NER and HRR in the absence of Lig1. Supporting observations are available in less elaborate genetic models in mouse cells. Collectively, these observations raise Lig3 from a niche-ligase to a

  17. Schistosomal versus nonschistosomal variceal bleeders. Do they respond differently to selective shunt (DSRS)?

    PubMed Central

    Ezzat, F A; Abu-Elmagd, K M; Sultan, A A; Aly, M A; Fathy, O M; Bahgat, O O; el-Fiky, A M; el-Barbary, M H; Mashhoor, N

    1989-01-01

    The distal splenorenal shunt (DSRS) was performed in 125 consecutive variceal bleeders. To date, no patients have been lost to follow-up (mean of 79 +/- 20 months). Liver pathology was documented in 85 patients: 45 patients had schistosomal hepatic fibrosis, 17 had nonalcoholic cirrhosis, and 23 had mixed pattern (hepatic fibrosis and cirrhosis). The preoperative data base for these three groups was matched (p greater than 0.05), with a mean follow-up of 79 +/- 20, 70 +/- 14, and 77 +/- 22 months for each population, respectively. The results showed low operative mortality (4.8%), high cumulative patency rate (94.8%) and low recurrent variceal hemorrhage (5.6%). The biochemical data showed significant increase in serum bilirubin (p less than 0.001) and aspartate transaminase (AST) (p less than 0.05) in the nonschistosomal patients. Chronic hyperbilirubinemia was found in 33% of the schistosomal group. Prograde portal perfusion was detected in 94% of the patients, with development of collaterals in 91%. The angiographic pattern of these collaterals was 50% pancreatic, 45% gastric, and 26% colosplenic. Patients with mixed liver disease had a high incidence of Grade III portal perfusion (57%) and more common pancreatic and gastric collaterals (71%). The cumulative survival for all patients was 74.1%, with hepatic cell failure being the leading cause of death (13 patients, 50% of all deaths). The schistosomal patients had a 91.6% incidence, whereas the cirrhotic and mixed groups had survival rates of 75.6% and 65.2%, respectively. Also, of a 15% total incidence of encephalopathy, 4.4% was related to the schistosomal patients, 23.5% to the cirrhotics, and 21.7% to the mixed population. Statistically, the survival rate was significantly better (p less than 0.05) and encephalopathy was significantly lower (p less than 0.05) in the schistosomal population. In conclusion, this data shows that: 1) DSRS has a high patency rate and a low variceal hemorrhage recurrence rate; 2

  18. Regression of esophageal varices and splenomegaly in two patients with hepatitis-C-related liver cirrhosis after interferon and ribavirin combination therapy

    PubMed Central

    Lee, Soon Jae; Cho, Yoo-Kyung; Na, Soo-Young; Choi, Eun Kwang; Boo, Sun Jin; Jeong, Seung Uk; Song, Hyung Joo; Kim, Heung Up; Kim, Bong Soo; Song, Byung-Cheol

    2016-01-01

    Some recent studies have found regression of liver cirrhosis after antiviral therapy in patients with hepatitis C virus (HCV)-related liver cirrhosis, but there have been no reports of complete regression of esophageal varices after interferon/peg-interferon and ribavirin combination therapy. We describe two cases of complete regression of esophageal varices and splenomegaly after interferon-alpha and ribavirin combination therapy in patients with HCV-related liver cirrhosis. Esophageal varices and splenomegaly regressed after 3 and 8 years of sustained virologic responses in cases 1 and 2, respectively. To our knowledge, this is the first study demonstrating that complications of liver cirrhosis, such as esophageal varices and splenomegaly, can regress after antiviral therapy in patients with HCV-related liver cirrhosis. PMID:27572075

  19. Kinetic framework for ligation by an efficient RNA ligase ribozyme.

    PubMed

    Bergman, N H; Johnston, W K; Bartel, D P

    2000-03-21

    The class I RNA ligase ribozyme, isolated previously from random sequences, performs an efficient RNA ligation reaction. It ligates two substrate RNAs, promoting the attack of the 3'-hydroxyl of one substrate upon the 5'-triphosphate of the other substrate with release of pyrophosphate. This ligation reaction has similarities to the reaction catalyzed by RNA polymerases. Using data from steady-state kinetic measurements and pulse-chase/pH-jump experiments, we have constructed minimal kinetic frameworks for two versions of the class I ligase, named 207t and 210t. For both ligases, as well as for the self-ligating parent ribozyme, the rate constant for the chemical step (k(c)) is log-linear with pH in the range 5.7-8.0. At physiological pH, the k(c) is 100 min(-1), a value similar to those reported for the fastest naturally occurring ribozymes. At higher pH, product release is limiting for both 207t and 210t. The 210t ribozyme, with its faster product release, attains multiple-turnover rates (k(cat) = 360 min(-1), pH 9.0) exceeding those of 207t and other reported ribozyme reactions. The kinetic framework for the 210t ribozyme describes the limits of this catalysis and suggests how key steps can be targeted for improvement using design or combinatorial approaches. PMID:10715133

  20. Aztreonam biliary excretion in bile duct ligated jaundiced rats.

    PubMed

    Rulli, F; Muzi, M; Zanella, E; Cipriani, P; Magni, A; Giordano, A; Filadoro, F

    1991-04-01

    An experimental study was undertaken to assess aztreonam biliary concentrations in bile duct ligated jaundiced rats. The study proved that aztreonam biliary concentrations are sufficient to inhibit Gram-negative bacteria within the first and the second hour after antibiotic administration. The experimental model suggests that clinical conditions such as lithiasis or neoplasms of the biliary tree should not totally inhibit the antibiotic excretion.

  1. The effect of ligation method on friction in sliding mechanics.

    PubMed

    Hain, Max; Dhopatkar, Ashish; Rock, Peter

    2003-04-01

    During orthodontic tooth movement with the preadjusted edgewise system, friction generated at the bracket/archwire interface tends to impede the desired movement. The method of ligation is an important contributor to this frictional force. This in vitro study investigated the effect of ligation method on friction and evaluated the efficacy of the new slick elastomeric modules from TP Orthodontics (La Porte, Ind), which are claimed to reduce friction at the module/wire interface. Slick modules were compared with regular nonslick modules, stainless steel ligatures, and the SPEED self-ligating bracket system (Strite Industries, Cambridge, Ontario, Canada). The effect of using slick modules with metal-reinforced ceramic (Clarity, 3M Unitek, Monrovia, Calif) and miniature brackets (Minitwin, 3M Unitek) was also examined. Results showed that, when considering tooth movement along a 0.019 x 0.025-in stainless steel archwire, saliva-lubricated slick modules can reduce static friction at the module/archwire interface by up to 60%, regardless of the bracket system. The SPEED brackets produced the lowest friction compared with the 3 other tested bracket systems when regular modules were used. The use of slick modules, however, with all of the ligated bracket types tested significantly reduced friction to below the values recorded in the SPEED groups. Loosely tied stainless steel ligatures were found to generate the least friction. PMID:12695769

  2. Matrix-assisted polymer pen lithography induced Staudinger Ligation.

    PubMed

    Bian, Shudan; Schesing, Kevin B; Braunschweig, Adam B

    2012-05-21

    The Staudinger Ligation has been combined with Polymer Pen Lithography to create patterns of fluorescent and redox-active inks with 1-micrometer scale feature diameters over centimeter-scale areas. This report presents a straightforward strategy to expand the scope of organic reactions employed in surface science. PMID:22509494

  3. The effect of ligation method on friction in sliding mechanics.

    PubMed

    Hain, Max; Dhopatkar, Ashish; Rock, Peter

    2003-04-01

    During orthodontic tooth movement with the preadjusted edgewise system, friction generated at the bracket/archwire interface tends to impede the desired movement. The method of ligation is an important contributor to this frictional force. This in vitro study investigated the effect of ligation method on friction and evaluated the efficacy of the new slick elastomeric modules from TP Orthodontics (La Porte, Ind), which are claimed to reduce friction at the module/wire interface. Slick modules were compared with regular nonslick modules, stainless steel ligatures, and the SPEED self-ligating bracket system (Strite Industries, Cambridge, Ontario, Canada). The effect of using slick modules with metal-reinforced ceramic (Clarity, 3M Unitek, Monrovia, Calif) and miniature brackets (Minitwin, 3M Unitek) was also examined. Results showed that, when considering tooth movement along a 0.019 x 0.025-in stainless steel archwire, saliva-lubricated slick modules can reduce static friction at the module/archwire interface by up to 60%, regardless of the bracket system. The SPEED brackets produced the lowest friction compared with the 3 other tested bracket systems when regular modules were used. The use of slick modules, however, with all of the ligated bracket types tested significantly reduced friction to below the values recorded in the SPEED groups. Loosely tied stainless steel ligatures were found to generate the least friction.

  4. ALCOHOLIC VERSUS NONALCOHOLIC CIRRHOSIS IN A RANDOMIZED CONTROLLED TRIAL OF EMERGENCY THERAPY OF BLEEDING VARICES

    PubMed Central

    Orloff, Marshall J.; Isenberg, Jon I.; Wheeler, Henry O.; Haynes, Kevin S.; Jinich-Brook, Horacio; Rapier, Roderick; Vaida, Florin; Hye, Robert J.; Orloff, Susan L.

    2010-01-01

    Background It has been proposed that portal-systemic shunts be avoided in alcoholic cirrhotics because survival rate is allegedly lower in alcoholics than in nonalcoholics. We examined this issue in a randomized controlled trial. Methods 211 unselected, consecutive patients with cirrhosis and bleeding esophageal varices were randomized to endoscopic sclerotherapy (EST) (n=106) or emergency portacaval shunt (EPCS) (105). Treatment was initiated within 8 hours. EST failure was treated by rescue PCS. 10-yr follow-up was 96%. Results Results strongly favored EPCS over EST (p<0.001). Among EPCS patients, 83% were alcoholic and 17% nonalcoholic. Outcomes were (1) permanent control of bleeding 100% vs. 100%; (2) 5-yr survival 71% vs.78%; (3) encephalopathy 14% vs. 19%; (4) yearly charges $38,300 vs. $43,000. Conclusions EPCS results were similar in alcoholic and nonalcoholic cirrhotics. EPCS is an effective first line emergency treatment in all forms of cirrhosis, including alcoholic. PMID:21195430

  5. Extensive gastric varices demonstrated by technetium-99m red blood cell scintigraphy

    SciTech Connect

    Shih, W.J.; Domstad, P.A.; Loh, F.G.; Pulmano, C.

    1987-04-01

    An alcohol abuse patient complicated by chronic pancreatitis had splenic vein thrombosis leading to gastric varices and underwent abdominal Tc-99m red blood cell scintigraphy. First pass study, sequential images up to 1 hour, and a 2.5 hour image showed abnormal radioactivity in the left side of the abdomen and midabdomen. In 24 hour images, the high level of activity in the left side persisted; in addition, there was accumulation of radioactivity in the cecum, ascending, transverse colon, the splenic flexure, and descending colon. A splenectomy was performed and during the surgical procedure, a large dilated vein in the greater omentum was noted. It is reemphasized that delayed imaging up to 24 hours is important when the results of earlier images are equivocal or negative.

  6. Transjugular intrahepatic portosystemic shunt vs endoscopic therapy in preventing variceal rebleeding

    PubMed Central

    Xue, Hui; Zhang, Meng; Pang, Jack XQ; Yan, Fei; Li, Ying-Chao; Lv, Liang-Shan; Yuan, Jia; Palikhe, Muna; Li, Wei-Zhi; Wang, Zhi-Lun

    2012-01-01

    AIM: To compare early use of transjugular intrahepatic portosystemic shunt (TIPS) with endoscopic treatment (ET) for the prophylaxis of recurrent variceal bleeding. METHODS: In-patient data were collected from 190 patients between January 2007 and June 2010 who suffured from variceal bleeding. Patients who were older than 75 years; previously received surgical treatment or endoscopic therapy for variceal bleeding; and complicated with hepatic encephalopathy or hepatic cancer, were excluded from this research. Thirty-five cases lost to follow-up were also excluded. Retrospective analysis was done in 126 eligible cases. Among them, 64 patients received TIPS (TIPS group) while 62 patients received endoscopic therapy (ET group). The relevant data were collected by patient review or telephone calls. The occurrence of rebleeding, hepatic encephalopathy or other complications, survival rate and cost of treatment were compared between the two groups. RESULTS: During the follow-up period (median, 20.7 and 18.7 mo in TIPS and ET groups, respectively), rebleeding from any source occurred in 11 patients in the TIPS group as compared with 31 patients in the ET group (Kaplan-Meier analysis and log-rank test, P = 0.000). Rebleeding rates at any time point (6 wk, 1 year and 2 year) in the TIPS group were lower than in the ET group (Bonferroni correction α’ = α/3). Eight patients in the TIPS group and 16 in the ET group died with the cumulative survival rates of 80.6% and 64.9% (Kaplan-Meier analysis and log-rank test χ2 = 4.864, P = 0.02), respectively. There was no significant difference between the two groups with respect to 6-wk survival rates (Bonferroni correction α’ = α/3). However, significant differences were observed between the two groups in the 1-year survival rates (92% and 79%) and the 2-year survival rates (89% and 64.9%) (Bonferroni correction α’ = α/3). No significant differences were observed between the two treatment groups in the occurrence of

  7. Correlation of HVPG Level with CTP Score, MELD Score, Ascites, Size of Varices, and Etiology in Cirrhotic Patients

    PubMed Central

    Ramanathan, Subramaniam; Khandelwal, Niranjan; Kalra, Naveen; Bhatia, Anmol; Dhiman, Radha K.; Duseja, Ajay K.; Chawla, Yogesh K.

    2016-01-01

    Background/Aim: This study intends to determine the correlation of a patient's hepatic venous pressure gradient (HVPG) measurement with six factors: Child–Turcotte–Pugh (CTP) score, model for end-stage liver disease (MELD) score, presence of ascites, size of varices, presence of variceal bleeding, and an etiology of cirrhosis. The study also aims to identify the predictors of higher HVPG measurements that can indirectly affect the prognosis of cirrhotic patients. Patients and Methods: Thirty patients diagnosed with cirrhosis were enrolled prospectively and each patient's HVPG level was measured by the transjugular catheterization of the right or middle hepatic vein. The wedged hepatic venous pressure (WHVP) and free hepatic venous pressure (FHVP) were measured using a 7F balloon catheter. The HVPG level was calculated as the difference between the WHVP and FHVP measurements. Results: The mean HVPG level was higher in alcoholic than in nonalcoholic cirrhosis (19.5 ± 7.3 vs 15.2 ± 4.5 mm Hg, P = 0.13). The mean HVPG was also higher in bleeders compared with nonbleeders (18.5 ± 5.3 vs 10.7 ± 3.1 mmHg, P = 0.001). Patients with varices had a higher mean HVPG level than those without varices (17.4 ± 5.8 vs 11.7 ± 3.9 mmHg, P = 0.04). The difference among the three categories of varices (small, large, and no varices) was statistically significant (P = 0.03). In addition, the mean HVPG level was higher in patients with ascites than in those without ascites (18.7 ± 4.7 vs 11 ± 5.3 mmHg, P = 0.002), and it was significantly higher in patients in CTP class C (21.8 ± 5.5 mmHg) as compared with those in CTP class B (16.9 ± 2.9 mmHg) and CTP class A (10.5 ± 4.1 mmHg; P ≤ 0.001). Conclusion: HVPG levels were significantly higher in patients in CTP class C as compared with those in CTP classes A and B, thereby indicating that an HVPG measurement correlates with severity of liver disease. A high HVPG level signifies more severe liver disease and can predict the

  8. Does adding variceal status to the Child-Turcotte-Pugh score improve its performance in predicting mortality in cirrhosis?

    PubMed

    Fan, Xiaoli; Wen, Maoyao; Shen, Yi; Wang, Wanqin; Yang, Xiaoxue; Yang, Li

    2016-09-01

    The Child-Turcotte-Pugh (CTP) score is widely used worldwide to predict outcomes across a broad spectrum of liver diseases, mainly cirrhosis. Portal hypertension and variceal bleed are significant causes of morbidity and mortality in cirrhotic patients, although the variceal status is not incorporated into the classical CTP score. We sought to determine whether the inclusion of variceal status, specifically the Child-Turcotte-Pugh-Kumar (CTPK) score, would improve the utility of the classical CTP score to predict the clinical outcomes of cirrhotic patients in a single but high-volume center in China.We retrospectively analyzed the records of 253 patients from January 1, 2014 to December 31, 2014 and performed follow-up for at least 12 months. The CTPK score and the CTP score were obtained as soon as possible after the patient's admission. Telephone follow-up was performed to assess survival situations.At 3 and 12 months, the cumulative number of deaths was 9.1% (n = 23) and 13.8% (n = 35), respectively. In the multivariate Cox proportional hazards models, the CTPK score was independently associated with death within 3 and 12 months after adjusting for potential confounders. The predictive ability related to the 2 scores was evaluated by the area under the receiver operating characteristic curve (AUC-ROC) respectively. At 3 months of enrollment, the AUCs of CTPK and CTP were 0.814 and 0.838, respectively. At 12 months of enrollment, the AUCs of CTPK and CTP were 0.825 and 0.840, respectively. No significant difference between time points was observed. Both the CTPK score and the CTP score displayed prognostic value in cirrhotic patients, as the Kaplan-Meier analysis showed that the CTPK score could clearly discriminate patients in the intermediate term (P < 0.001).The CTPK score provides reliable prediction of mortality in Chinese cirrhotic patients for both short-term and medium-term prognoses, although it is not superior to the CTP score. Therefore, the CTP

  9. Does adding variceal status to the Child–Turcotte–Pugh score improve its performance in predicting mortality in cirrhosis?

    PubMed Central

    Fan, Xiaoli; Wen, Maoyao; Shen, Yi; Wang, Wanqin; Yang, Xiaoxue; Yang, Li

    2016-01-01

    Abstract The Child–Turcotte–Pugh (CTP) score is widely used worldwide to predict outcomes across a broad spectrum of liver diseases, mainly cirrhosis. Portal hypertension and variceal bleed are significant causes of morbidity and mortality in cirrhotic patients, although the variceal status is not incorporated into the classical CTP score. We sought to determine whether the inclusion of variceal status, specifically the Child–Turcotte–Pugh–Kumar (CTPK) score, would improve the utility of the classical CTP score to predict the clinical outcomes of cirrhotic patients in a single but high-volume center in China. We retrospectively analyzed the records of 253 patients from January 1, 2014 to December 31, 2014 and performed follow-up for at least 12 months. The CTPK score and the CTP score were obtained as soon as possible after the patient's admission. Telephone follow-up was performed to assess survival situations. At 3 and 12 months, the cumulative number of deaths was 9.1% (n = 23) and 13.8% (n = 35), respectively. In the multivariate Cox proportional hazards models, the CTPK score was independently associated with death within 3 and 12 months after adjusting for potential confounders. The predictive ability related to the 2 scores was evaluated by the area under the receiver operating characteristic curve (AUC-ROC) respectively. At 3 months of enrollment, the AUCs of CTPK and CTP were 0.814 and 0.838, respectively. At 12 months of enrollment, the AUCs of CTPK and CTP were 0.825 and 0.840, respectively. No significant difference between time points was observed. Both the CTPK score and the CTP score displayed prognostic value in cirrhotic patients, as the Kaplan–Meier analysis showed that the CTPK score could clearly discriminate patients in the intermediate term (P < 0.001). The CTPK score provides reliable prediction of mortality in Chinese cirrhotic patients for both short-term and medium-term prognoses, although it is not superior to the CTP

  10. Corrosion behavior of self-ligating and conventional metal brackets

    PubMed Central

    Maia, Lúcio Henrique Esmeraldo Gurgel; Lopes Filho, Hibernon; Ruellas, Antônio Carlos de Oliveira; Araújo, Mônica Tirre de Souza; Vaitsman, Delmo Santiago

    2014-01-01

    Objective To test the null hypothesis that the aging process in self-ligating brackets is not higher than in conventional brackets. Methods Twenty-five conventional (GN-3M/Unitek; GE-GAC; VE-Aditek) and 25 self-ligating (SCs-3M/Unitek; INs-GAC; ECs-Aditek) metal brackets from three manufacturers (n = 150) were submitted to aging process in 0.9% NaCl solution at a constant temperature of 37 ± 1ºC for 21 days. The content of nickel, chromium and iron ions in the solution collected at intervals of 7, 14 and 21 days was quantified by atomic absorption spectrophotometry. After the aging process, the brackets were analyzed by scanning electron microscopy (SEM) under 22X and 1,000X magnifications. Results Comparison of metal release in self-ligating and conventional brackets from the same manufacturer proved that the SCs group released more nickel (p < 0.05) than the GN group after 7 and 14 days, but less chromium (p < 0.05) after 14 days and less iron (p < 0.05) at the three experimental time intervals. The INs group released less iron (p < 0.05) than the GE group after 7 days and less nickel, chromium and iron (p < 0.05) after 14 and 21 days. The ECs group released more nickel, chromium and iron (p < 0.05) than the VE group after 14 days, but released less nickel and chromium (p < 0.05) after 7 days and less chromium and iron (p < 0.05) after 21 days. The SEM analysis revealed alterations on surface topography of conventional and self-ligating brackets. Conclusions The aging process in self-ligating brackets was not greater than in conventional brackets from the same manufacturer. The null hypothesis was accepted. PMID:24945521

  11. Novel predictors for immediate puncture site bleed during endoscopic glue injection for gastric varices without using lipiodol.

    PubMed

    Chandrasekar, T S; Menachery, John; Gokul, B J; Murugesh, M; Vivek Sandeep, T C

    2013-05-01

    Endoscopic obturation of gastric varices using tissue adhesive glues like cyanoacrylate is an accepted modality for the treatment of gastric varices. This study was undertaken to determine whether it was possible to predict immediate puncture site bleed on withdrawal of needle catheter during endoscopic glue injection without lipiodol. We prospectively analyzed 100 consecutive patients with cirrhosis who underwent glue injection. Glue injection was successful in all the patients. Immediate puncture site bleed was observed in only four cases and all of them correlated with negative catheter pull sign and positive red catheter sign. Catheter pull sign and red catheter sign were excellent predictors of immediate puncture site bleed during endoscopic glue injection and should be routinely tested.

  12. Repeated pancreatitis-induced splenic vein thrombosis leads to intractable gastric variceal bleeding: A case report and review.

    PubMed

    Tang, Shan-Hong; Zeng, Wei-Zheng; He, Qian-Wen; Qin, Jian-Ping; Wu, Xiao-Ling; Wang, Tao; Wang, Zhao; He, Xuan; Zhou, Xiao-Lei; Fan, Quan-Shui; Jiang, Ming-De

    2015-10-16

    Gastric varices (GV) are one of the most common complications for patients with portal hypertension. Currently, histoacryl injection is recommended as the initial treatment for bleeding of GV, and this injection has been confirmed to be highly effective for most patients in many studies. However, this treatment might be ineffective for some types of GV, such as splenic vein thrombosis-related localized portal hypertension (also called left-sided, sinistral, or regional portal hypertension). Herein, we report a case of repeated pancreatitis-induced complete splenic vein thrombosis that led to intractable gastric variceal bleeding, which was treated by splenectomy. We present detailed radiological and pathological data and blood rheology analysis (the splenic artery - after a short gastric vein or stomach vein - gastric coronary vein - portal vein). The pathophysiology can be explained by the abnormal direction of blood flow in this patient. To our knowledge, this is the first reported case for which detailed pathology and blood rheology data are available.

  13. Ligation-free ribosome profiling of cell type-specific translation in the brain.

    PubMed

    Hornstein, Nicholas; Torres, Daniela; Das Sharma, Sohani; Tang, Guomei; Canoll, Peter; Sims, Peter A

    2016-01-01

    Ribosome profiling has emerged as a powerful tool for genome-wide measurements of translation, but library construction requires multiple ligation steps and remains cumbersome relative to more conventional deep-sequencing experiments. We report a new, ligation-free approach to ribosome profiling that does not require ligation. Library construction for ligation-free ribosome profiling can be completed in one day with as little as 1 ng of purified RNA footprints. We apply ligation-free ribosome profiling to mouse brain tissue to identify new patterns of cell type-specific translation and test its ability to identify translational targets of mTOR signaling in the brain.

  14. [Bleeding oesophageal varices in a seven-year-old boy supposedly as a late complication to neonatal umbilical venous catheter].

    PubMed

    Rogvi, Rasmus Á; Møller, Fie Gregersen; Bergström, Anita; Ifaoui, Inge Bøtker; Jørgensen, Marianna Hørby

    2016-05-30

    A seven-year-old boy was admitted with haematemesis. The boy was originally born at 27 weeks' gestational age. His neonatal period had been complicated by sepsis, for which he was treated with antibiotics through an umbilical venous catheter (UVC). A gastroscopy showed grade III oesophageal varices with bleeding. He was examined thoroughly for other causes of portal hypertension, but none were found. Portal hypertension caused by UVC in the neonatal period is a rare but very serious complication to neonatal UVC.

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

    PubMed Central

    Elwakil, Reda; Montasser, Mohamed Fawzy; Abdelhakam, Sara M; Ibrahim, Wesam A

    2015-01-01

    AIM: To compare n-butyl-2-cyanoacrylate, iso-amyl-2-cyanoacrylate and a mixture of 72% chromated glycerin with hypertonic glucose solution in management of gastric varices. METHODS: Ninety patients with gastric varices presented to Endoscopy Unit of Ain Shams University Hospital were included. They were randomly allocated into three groups; each group included 30 patients treated with intravariceal sclerosant injections in biweekly sessions till complete obturation of gastric varices; Group I (n-butyl-2-cyanoacrylate; Histoacryl®), Group II (iso-amyl-2-cyanoacrylate; Amcrylate®) and Group III (mixture of 72% chromated glycerin; Scleremo® with glucose solution 25%). All the procedures were performed electively without active bleeding. Recruited patients were followed up for 3 mo. RESULTS: 26% of Scleremo group had bleeding during puncture vs 3.3% in each of the other two groups with significant difference, (P < 0.05). None of Scleremo group had needle obstruction vs 13.3% in each of the other two groups with no significant difference, (P > 0.05). Rebleeding occurred in 13.3% of Histoacryl and Amcrylate groups vs 0% in Scleremo group with no significant difference. The in hospital mortality was 6.6% in both Histoacryl and Amcrylate groups, while it was 0% in Scleremo group with no significant difference. In the first and second sessions, the amount of Scleremo needed 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. PMID:25901221

  16. An Unusual Case of Gastrointestinal Bleeding from Isolated Gallbladder Varices in a Patient with Pancreatic Cancer Complicated by Portal Biliopathy

    PubMed Central

    Kubachev, Kubach; Abdullaev, Elbrus; Zarkua, Nonna; Abdullaev, Abakar; Fokin, Artur

    2016-01-01

    Portal biliopathy is the complex of abnormalities of extrahepatic and intrahepatic bile ducts, cystic duct, and gallbladder, arising as a result of extrahepatic portal vein obstruction and noncirrhotic portal fibrosis, which can be caused by coagulopathies, tumors, inflammation, postoperative complications, dehydration, and neonatal umbilical vein catheterization. We report a case of a 55-year-old male patient with the history of pancreatic cancer and cholecystoenteric anastomosis presenting with gastrointestinal bleeding from gallbladder varices via the anastomosis. PMID:27800195

  17. Ectopic Jejunal Variceal Rupture in a Liver Transplant Recipient Successfully Treated With Percutaneous Transhepatic Coil Embolization: A Case Report.

    PubMed

    Abe, Satoru; Akamatsu, Nobuhisa; Hoshikawa, Mayumi; Shirata, Chikara; Sakamoto, Yoshihiro; Hasegawa, Kiyoshi; Kokudo, Norihiro

    2015-11-01

    Here we present the rupture of ectopic jejunal varices developing in a liver transplant recipient without portal hypertension, which was successfully treated with percutaneous transhepatic coil embolization.A 48-year-old man with massive melena was admitted to our department. He had undergone liver transplantation for hepatitis B virus-related liver cirrhosis 8 months before, and his postoperative course was satisfactory except for an acute cellular rejection. No evidence of bleeding was detected by upper endoscopy or colonoscopy, but dynamic multidetector computed tomography of the whole abdomen revealed an intestinal varix protruding into the lumen of the jejunum with suspected extravasation. There was no evidence of portal venous stenosis or thrombosis. Immediately upon diagnosis of the ruptured ectopic jejunal varix, percutaneous transhepatic coil embolization was performed, achieving complete hemostasis. The portal venous pressure measured during the procedure was within normal limits. He was discharged from the hospital 11 days after embolization and remained in stable condition without re-bleeding 6 months after discharge.This is the first report of an ectopic intestinal variceal rupture in an uneventful liver transplant recipient that was successfully treated with interventional percutaneous transhepatic coil embolization. Clinicians encountering liver transplant recipients with melena should be aware of the possibility of late-onset rupture of ectopic varices, even in those having an uneventful post-transplant course without portal hypertension. PMID:26632745

  18. Real-time monitoring of nucleic acid ligation in homogenous solutions using molecular beacons.

    PubMed

    Tang, Zhiwen; Wang, Kemin; Tan, Weihong; Li, Jun; Liu, Lingfeng; Guo, Qiuping; Meng, Xiangxian; Ma, Changbei; Huang, Shasheng

    2003-12-01

    Nucleic acids ligation is a vital process in the repair, replication and recombination of nucleic acids. Traditionally, it is assayed by denatured gel electrophoresis and autoradiography, which are not sensitive, and are complex and discontinuous. Here we report a new approach for ligation monitoring using molecular beacon DNA probes. The molecular beacon, designed in such a way that its sequence is complementary with the product of the ligation process, is used to monitor the nucleic acid ligation in a homogeneous solution and in real-time. Our method is fast and simple. We are able to study nucleic acids ligation kinetics conveniently and to determine the activity of DNA ligase accurately. We have studied different factors that influence DNA ligation catalyzed by T4 DNA ligase. The major advantages of our method are its ultrasensitivity, excellent specificity, convenience and real-time monitoring in homogeneous solution. This method will be widely useful for studying nucleic acids ligation process and other nucleic acid interactions.

  19. Doctor Knows Best? Tubal Ligation in Young, Childless Women.

    PubMed

    Goldrath, Kathryn; Smith, Lauren B

    2016-09-01

    When a gynecologist asks a twenty-one-year-old patient about her use of contraception, he is surprised that she would like to have a tubal ligation. The patient says that she would "never want to bring a child into this screwed up world." She has discussed tubal ligation with her boyfriend of one year, and he has told her that he accepts her decision. She asks her doctor if she can schedule the procedure as soon as possible. Her gynecologist mentions that he is concerned that she is very young and may eventually change her mind about having children. She insists that she has thought about it carefully and is certain that she wants the procedure. Her doctor feels very uncomfortable about this request. He consults the hospital ethics committee. Should he do as the patient asks or suggest that she wait at least six months and reconsider? PMID:27649822

  20. Venous outflow of the brain after bilateral complete jugular ligation.

    PubMed

    Ensari, Serdar; Kaptanoğlu, Erkan; Tun, Kağan; Gün, Taylan; Beşkonakli, Etem; Celikkanat, Serdar; Dere, Hüseyin; Cekirge, Saruhan

    2008-01-01

    A case of a patient with bilateral internal, external, posterior external and anterior jugular vein ligations and excisions performed in the neck due to a larynx tumor is presented. Radical neck dissection is a standard otorhinolaryngological procedure in the management of head and neck cancer patients with bilateral lymph node metastasis to the neck. Sacrifice of both internal and external jugular veins bilaterally has been recognized as a dangerous approach leading to intracranial hypertension with subsequent neurological sequela and death. In this report, we aimed to demonstrate how venous outflow from the brain diverts after jugular venous system obliteration. After bilateral jugular vein ligations, digital subtraction angiography (DSA) showed that the venous drainage route of the brain had been diverted from the jugular veins to the vertebral venous plexus. PMID:18382980

  1. Lymphatic dysfunction after ligation surgery for varicose vein

    PubMed Central

    Hara, Hisako; Mihara, Makoto; Hasegawa, Kyoko; Yamanaka, Kazuko

    2016-01-01

    Objective: Although the lymphatic complications such as lymphocele sometimes occur after surgery for varicose veins, the lymphatic function of such patients has not been evaluated. In this case report, we present a case of lymphocele after ligation surgery for varicose vein. We also detected subclinical dysfunction in lower limb using indocyanine green (ICG) lymphography. Case report: A 76 year- old female underwent ligation surgery for right lower leg varicose vein, and she noticed the squashy lesion in the medial side of the right knee. Three years later, she consulted our clinic and we performed ICG lymphography. We observed dermal backflow around the mass, which indicated lymphatic dysfunction. After injecting additional ICG around the knee, we punctured and drained the clear, yellow fluid from the mass and it was contrasted with ICG during the examination and the involvement of the lymphatic system was proven. PMID:27757234

  2. Endoscopic management of bleeding gastric varices with N-butyl, 2-cyanoacrylate glue injection in children with non-cirrhotic portal hypertension

    PubMed Central

    Poddar, Ujjal; Borkar, Vibhor; Yachha, Surender Kumar; Srivastava, Anshu

    2016-01-01

    Background and study aims: In view of the paucity of literature, we carried out this audit to evaluate the safety and efficacy of N- butyl, 2-cynoacrylate glue injection therapy in secondary prophylaxis of gastric varices in children. Patients and methods: Consecutive children (≤ 18 years) with non-cirrhotic portal hypertension who presented with bleeding from gastric varices and who had undergone cyanoacrylate glue injection therapy were included. They were evaluated for safety, efficacy and complications. Their long-term outcomes and follow-up were recorded. Results: Over 11 years, 28 children with median age 13 (range, 8 to 18) years (68 % boys), underwent cyanoacrylate glue injection for bleeding gastric varices. In 25 (89 %) cases, extrahepatic portal venous obstruction was the etiology and isolated gastric varices were the source of the bleeding. Primary and secondary gastric variceal bleeding was seen in 11 (39 %) and 17 (61 %) children, respectively. A total 36 sessions with median volume of 2 (range, 1 – 5) mL of glue injections were required (2 sessions in 8 children). Hemostasis was achieved in all and 57 % had gastric variceal obliteration. Two children had early (< 1 month) rebleeding and 2 children had late rebleeding. One child had gastric ulcer. Over a median follow-up of 24 (8 – 98) months, 14 children underwent surgery (12 porto-systemic shunt), 2 were lost to follow-up, 1 died and there was no recurrence of bleeding in the remaining 11. Conclusions: Cyanoacrylate glue injection is highly effective mode of secondary prophylaxis of bleeding gastric varices in children with non-cirrhotic portal hypertension. Rebleeding occurred in 14 % but treatment-related complications were uncommon. However, a large controlled clinical trial is required to confirm our findings. PMID:27757413

  3. Sequence complementarity-driven nonenzymatic ligation of RNA.

    PubMed

    Pino, Samanta; Costanzo, Giovanna; Giorgi, Alessandra; Di Mauro, Ernesto

    2011-04-12

    We report two reactions of RNA G:C sequences occurring nonenzymatically in water in the absence of any added cofactor or metal ion: (a) sequence complementarity-driven terminal ligation and (b) complementary sequence adaptor-driven multiple tandemization. The two abiotic reactions increase the chemical complexity of the resulting pool of RNA molecules and change the Shannon information of the initial population of sequences.

  4. Anesthetic Management During Emergency Surgical Ligation for Carotid Blowout Syndrome.

    PubMed

    Klein Nulent, Casper G A; de Graaff, Henri J D; Ketelaars, Rein; Sewnaik, Aniel; Maissan, Iscander M

    2016-08-15

    A 44-year-old man presented to our emergency department with a pharyngeal hemorrhage, 6 weeks after a total laryngectomy and extensive neck dissection. Immediate surgical intervention was necessary to stop massive arterial hemorrhage from the pharynx. The head and neck surgeon successfully ligated the common carotid artery during this procedure. We describe the anesthetic strategy and the thromboelastometry (ROTEM®)-guided massive transfusion protocol. PMID:27310900

  5. A Pictet-Spengler ligation for protein chemical modification

    PubMed Central

    Agarwal, Paresh; van der Weijden, Joep; Sletten, Ellen M.; Rabuka, David; Bertozzi, Carolyn R.

    2013-01-01

    Aldehyde- and ketone-functionalized proteins are appealing substrates for the development of chemically modified biotherapeutics and protein-based materials. Their reactive carbonyl groups are typically conjugated with α-effect nucleophiles, such as substituted hydrazines and alkoxyamines, to generate hydrazones and oximes, respectively. However, the resulting C=N linkages are susceptible to hydrolysis under physiologically relevant conditions, which limits the utility of such conjugates in biological systems. Here we introduce a Pictet-Spengler ligation that is based on the classic Pictet-Spengler reaction of aldehydes and tryptamine nucleophiles. The ligation exploits the bioorthogonal reaction of aldehydes and alkoxyamines to form an intermediate oxyiminium ion; this intermediate undergoes intramolecular C–C bond formation with an indole nucleophile to form an oxacarboline product that is hydrolytically stable. We used the reaction for site-specific chemical modification of glyoxyl- and formylglycine-functionalized proteins, including an aldehyde-tagged variant of the therapeutic monoclonal antibody Herceptin. In conjunction with techniques for site-specific introduction of aldehydes into proteins, the Pictet-Spengler ligation offers a means to generate stable bioconjugates for medical and materials applications. PMID:23237853

  6. Long-term Results of Hemorrhoidal Artery Ligation.

    PubMed

    Yilmaz, İbrahim; Özgür Karakaş, Dursun; Sücüllü, İlker

    2016-03-01

    Aim of this study is to assess the efficacy, safety, and long-term results of doppler-guided hemorrhoidal artery ligation procedure with a 7-year follow-up period for treatment of grade II and III degree hemorrhoidal diseases. The procedure was performed by a specially designed proctoscope to locate and ligate all terminal branches of superior rectal artery. Patients were followed up at postoperative 1st week and 3rd, 12th, and 24th months by physical examination and 7th year by phone questionnaire using Short Form-36. Between November 2006 and May 2007, 50 patients (29 females, mean age = 38.2) underwent this procedure. All patients discharged at operation day and mean return to work was 2.5 days. There were no major complications and mean postoperative Visual Analogous Scale at first week was 1.72. At 24th month, 44 (88%) and 38 (76%) patients at 7th year were symptom free. Doppler-guided hemorrhoidal artery ligation is a safe, effective, and outpatient procedure, which can be the treatment of choice for second- and third-degree hemorrhoidal diseases with satisfactory long-term results.

  7. RNA Ligation and the Origin of tRNA

    NASA Astrophysics Data System (ADS)

    Nagaswamy, Uma; Fox, George E.

    2003-04-01

    A straightforward origin of transfer RNA, (tRNA), is difficult to envision because of the apparently complex idiosyncratic interaction between the D-loop and T-loop. Recently, multiple examples of the T-loop structural motif have been identified in ribosomal RNA. These examples show that the long-range interactions between the T-loop and D-loops seen in tRNA are not an essential part of the motif but rather are facilitated by it. Thus, the core T-loop structure could already have existed in a small RNA prior to the emergence of the tRNA. The tRNA might then have arisen by expansion of an RNA that carried the motif. With this idea in mind, Di Giulio's earlier hypothesis that tRNA evolved by a simple duplication or ligation of a minihelix RNA was re-examined. It is shown that an essentially modern tRNA structure can in fact be generated by the ligation of two 38-nucleotide RNA minihelices of appropriate sequence. Although rare, such sequences occur with sufficient frequency, (1 in 3 × 107), that they could be found in a standard in vitro RNA selection experiment. The results demonstrate that a series of RNA duplications, as previously proposed, can in principal account for the origin of tRNA. More generally, the results point out that RNA ligation can be a powerful driving force for increased complexity in the RNA World.

  8. Ligation of CD38 suppresses human B lymphopoiesis

    PubMed Central

    1995-01-01

    CD38 is a transmembrane glycoprotein expressed in many cell types, including lymphoid progenitors and activated lymphocytes. High levels of CD38 expression on immature lymphoid cells suggest its role in the regulation of cell growth and differentiation, but there is no evidence demonstrating a functional activity of CD38 on these cells. We used stroma-supported cultures of B cell progenitors and anti-CD38 monoclonal antibodies (T16 and IB4) to study CD38 function. In cultures of normal bone marrow CD19+ cells (n = 5), addition of anti-CD38 markedly reduced the number of cells recovered after 7 d. Cell loss was greatest among CD19+ sIg- B cell progenitors (mean cell recovery +/- SD = 7.2 +/- 11.7% of recovery in control cultures) and extended to CD19+CD34+ B cells (the most immature subset; 7.6 +/- 2.2%). In contrast, CD38 ligation did not substantially affect cell numbers in cultures of normal peripheral blood or tonsillar B cells. In stroma- supported cultures of 22 B-lineage acute lymphoblastic leukemia cases, anti-CD38 suppressed recovery of CD19+ sIg- leukemic cells. CD38 ligation also suppressed the growth of immature lymphoid cell lines cultured on stroma and, in some cases, in the presence of stroma- derived cytokines (interleukin [IL] 7, IL-3, and/or stem cell factor), but did not inhibit growth in stroma- or cytokine-free cultures. DNA content and DNA fragmentation studies showed that CD38 ligation of stroma-supported cells resulted in both inhibition of DNA synthesis and induction of apoptosis. It is known that CD38 catalyzes nicotinamide adenine dinucleotide (NAD+) hydrolysis into cyclic ADP-ribose (cADPR) and ADPR. However, no changes in NAD+ hydrolysis or cADPR and ADPR production after CD38 ligation were found by high-performance liquid chromatography; addition of NAD+, ADPR, or cADPR to cultures of lymphoid progenitors did not offset the inhibitory effects of anti- CD38. Thus, anti-CD38 does not suppress B lymphopoiesis by altering the enzymatic

  9. Novel Therapeutic Strategies in the Management of Non-Variceal Upper Gastrointestinal Bleeding

    PubMed Central

    Garber, Ari; Jang, Sunguk

    2016-01-01

    Non-variceal upper gastrointestinal bleeding, the most common etiology of which is peptic ulcer disease, remains a persistent challenge despite a reduction in both its incidence and mortality. Both pharmacologic and endoscopic techniques have been developed to achieve hemostasis, with varying degrees of success. Among the pharmacologic therapies, proton pump inhibitors remain the mainstay of treatment, as they reduce the risk of rebleeding and requirement for recurrent endoscopic evaluation. Tranexamic acid, a derivative of the amino acid lysine, is an antifibrinolytic agent whose role requires further investigation before application. Endoscopically delivered pharmacotherapy, including Hemospray (Cook Medical), EndoClot (EndoClot Plus Inc.), and Ankaferd Blood Stopper (Ankaferd Health Products), in addition to standard epinephrine, show promise in this regard, although their mechanisms of action require further investigation. Non-pharmacologic endoscopic techniques use one of the following two methods to achieve hemostasis: ablation or mechanical tamponade, which may involve using endoscopic clips, cautery, argon plasma coagulation, over-the-scope clipping devices, radiofrequency ablation, and cryotherapy. This review aimed to highlight these novel and fundamental hemostatic strategies and the research supporting their efficacy. PMID:27744662

  10. Severe gastric variceal haemorrhage due to splenic artery thrombosis and consecutive arterial bypass

    PubMed Central

    2011-01-01

    Background Upper gastrointestinal haemorrhage is mainly caused by ulcers. Gastric varicosis due to portal hypertension can also be held responsible for upper gastrointestinal bleeding. Portal hypertension causes the development of a collateral circulation from the portal to the caval venous system resulting in development of oesophageal and gastric fundus varices. Those may also be held responsible for upper gastrointestinal haemorrhage. Case presentation In this study, we describe the case of a 69-year-old male with recurrent severe upper gastrointestinal bleeding caused by arterial submucosal collaterals due to idiopathic splenic artery thrombosis. The diagnosis was secured using endoscopic duplex ultrasound and angiography. The patient was successfully treated with a laparoscopic splenectomy and complete dissection of the short gastric arteries, resulting in the collapse of the submucosal arteries in the gastric wall. Follow-up gastroscopy was performed on the 12th postoperative week and showed no signs of bleeding and a significant reduction in the arterial blood flow within the gastric wall. Subsequent follow-up after 6 months also showed no further gastrointestinal bleeding as well as subjective good quality of life for the patient. Conclusion Submucosal arterial collaterals must be excluded by endosonography via endoscopy in case of recurrent upper gastrointestinal bleeding. Laparoscopic splenectomy provides adequate treatment in preventing any recurrent bleeding, if gastric arterial collaterals are caused by splenic artery thrombosis. PMID:21711534

  11. In Vitro Selection of Optimal DNA Substrates for Ligation by a Water-Soluble Carbodiimide

    NASA Technical Reports Server (NTRS)

    Harada, Kazuo; Orgel, Leslie E.

    1994-01-01

    We have used in vitro selection to investigate the sequence requirements for efficient template-directed ligation of oligonucleotides at 0 deg C using a water-soluble carbodiimide as condensing agent. We find that only 2 bp at each side of the ligation junction are needed. We also studied chemical ligation of substrate ensembles that we have previously selected as optimal by RNA ligase or by DNA ligase. As anticipated, we find that substrates selected with DNA ligase ligate efficiently with a chemical ligating agent, and vice versa. Substrates selected using RNA ligase are not ligated by the chemical condensing agent and vice versa. The implications of these results for prebiotic chemistry are discussed.

  12. Menstrual Pattern following Tubal Ligation: A Historical Cohort Study

    PubMed Central

    Sadatmahalleh, Shahideh Jahanian; Ziaei, Saeideh; Kazemnejad, Anoshirvan; Mohamadi, Eesa

    2016-01-01

    Background Tubal ligation (TL) is recommended for women who have completed their family planning. The existence of the menstrual disorders following this procedure has been the subject of debate for decades. This study was conducted to identify the relationship between tubal ligation and menstrual disorders. Materials and Methods A historical cohort study was carried out on 140 women undergoing tubal ligation (TL group) and on 140 women using condom as the main contraceptive method (Non-TL group). They aged between 20 and 40 years and were selected from a health care center in Rudsar, Guilan Province, Iran, during 2013-2014. The two groups were comparable in demographic characteristics, obstetrical features and menstrual bleeding pattern using a routine questionnaire. A validated pictorial blood loss assessment chart (PBLAC) was also used to measure the menstrual blood loss. Results Women with TL had more menstrual irregularity than those without TL (24.3 vs. 10%, P=0.002). Women with TL had more polymenorrhea (9.3 vs. 1.4%, P=0.006), hypermenorrhea (12.1 vs. 2.1%, P=0.002), menorrhagia (62.9 vs. 22.1%, P<0.0001) and menometrorrhagia (15.7 vs. 3.6%, P=0.001) than those without TL. There is a significant difference in the PBLAC score between women with and without TL (P<0.0001). According to logistic regression, age odds ratio [(OR=1.08, con- fidence interval (CI):1.07-1.17, P=0.03)], TL (OR=5.95, CI:3.45-10.26, P<0.0001) and cesarean section (OR=2.72, CI:1.49-4.97, P=0.001) were significantly associated with menorrhagia. Conclusion We found significant differences in menstrual disorders between women with and without TL. Therefore, women should be informed by the health providers regarding the advantages and disadvantages of TL before the procedures. PMID:26985334

  13. Expressed protein ligation for metalloprotein design and engineering.

    PubMed

    Clark, Kevin M; van der Donk, Wilfred A; Lu, Yi

    2009-01-01

    Metalloproteins contain highly specialized metal-binding sites that are designed to accept specific metal ions to maintain correct function. Although many of the sites have been modified with success, the relative paucity of functional group availability within proteinogenic amino acids can sometimes leave open questions about specific functions of the metal binding ligands. Attaining a more thorough analysis of individual amino acid function within metalloproteins has been realized using expressed protein ligation (EPL). Here we describe our recent efforts using EPL to incorporate nonproteinogenic cysteine and methionine analogues into the type 1 copper site found in Pseudomonas aeruginosa azurin.

  14. Amplification of target-specific, ligation-dependent circular probe.

    PubMed

    Zhang, D Y; Brandwein, M; Hsuih, T C; Li, H

    1998-05-12

    We describe a novel polymerase chain reaction (PCR)-based gene amplification method utilizing a circularizable oligodeoxyribonucleotide probe (C-probe). The C-probe contains two target complementary regions located at each terminus and an interposed generic PCR primer binding region. The hybridization of C-probe to a target brings two termini in direct apposition as the complementary regions of C-probe wind around the target to form a double helix. Subsequent ligation of the two termini results in a covalently linked C-probe that becomes 'locked on to' the target. The circular nature of the C-probe allows for the generation of a multimeric single-stranded DNA (ssDNA) via extension of the antisense primer by Taq DNA polymerase along the C-probe and displacement of downstream strand, analogous to 'rolling circle' replication of bacteriophage in vivo. This multimeric ssDNA then serves as a template for multiple sense primers to hybridize, extend, and displace downstream DNA, generating a large ramified (branching) DNA complex. Subsequent thermocycling denatures the dsDNA and initiates the next round of primer extension and ramification. This model results in significantly improved amplification kinetics (super-exponential) as compared to conventional PCR. Our results show that the C-probe was 1000 times more sensitive than the corresponding linear hemiprobes for detecting Epstein-Barr virus early RNA. The C-probe not only increases the power of amplification but also offers a means for decontaminating carryover amplicons. As the ligated C-probes possess no free termini, they are resistant to exonuclease digestion, whereas contaminated linear amplicons are susceptible to digestion. Treatment of the ligation reaction mixture with exonuclease prior to amplification eliminated the amplicon contaminant, which could also have been co-amplified with the same PCR primers; only the ligated C-probes were amplified. The combined advantages of the C-probe and thermocycling have a

  15. Amplification of target-specific, ligation-dependent circular probe.

    PubMed

    Zhang, D Y; Brandwein, M; Hsuih, T C; Li, H

    1998-05-12

    We describe a novel polymerase chain reaction (PCR)-based gene amplification method utilizing a circularizable oligodeoxyribonucleotide probe (C-probe). The C-probe contains two target complementary regions located at each terminus and an interposed generic PCR primer binding region. The hybridization of C-probe to a target brings two termini in direct apposition as the complementary regions of C-probe wind around the target to form a double helix. Subsequent ligation of the two termini results in a covalently linked C-probe that becomes 'locked on to' the target. The circular nature of the C-probe allows for the generation of a multimeric single-stranded DNA (ssDNA) via extension of the antisense primer by Taq DNA polymerase along the C-probe and displacement of downstream strand, analogous to 'rolling circle' replication of bacteriophage in vivo. This multimeric ssDNA then serves as a template for multiple sense primers to hybridize, extend, and displace downstream DNA, generating a large ramified (branching) DNA complex. Subsequent thermocycling denatures the dsDNA and initiates the next round of primer extension and ramification. This model results in significantly improved amplification kinetics (super-exponential) as compared to conventional PCR. Our results show that the C-probe was 1000 times more sensitive than the corresponding linear hemiprobes for detecting Epstein-Barr virus early RNA. The C-probe not only increases the power of amplification but also offers a means for decontaminating carryover amplicons. As the ligated C-probes possess no free termini, they are resistant to exonuclease digestion, whereas contaminated linear amplicons are susceptible to digestion. Treatment of the ligation reaction mixture with exonuclease prior to amplification eliminated the amplicon contaminant, which could also have been co-amplified with the same PCR primers; only the ligated C-probes were amplified. The combined advantages of the C-probe and thermocycling have a

  16. Proximal disruptor aided ligation (ProDAL) of kilobase-long RNAs.

    PubMed

    Zhovmer, Alexander; Qu, Xiaohui

    2016-07-01

    RNA with site-specific modification is a useful tool for RNA biology studies. However, generating kilobase (kb) -long RNA with internal modification at a site distant from RNA termini remains challenging. Here we report an enhanced splint ligation technique, proximal disruptor aided ligation (ProDAL), which allows adequate efficiency toward this purpose. The key to our approach is using multiple DNA oligonucleotides, 'proximal disruptors', to target the RNA substrate sequence next to the ligation site. The binding of disruptors helps to free the ligation site from intramolecular RNA basepairing, and consequently promotes more efficient formation of the pre-ligation complex and a higher overall ligation yield. We used naturally occurring 1.0 kb renilla and 1.9 kb firefly luciferase mRNA sequences to test the efficacy of our approach. ProDAL yielded 9-14% efficiency for the ligation between two RNA substrates, both of which were between 414 and 1313 nucleotides (nt) long. ProDAL also allowed similarly high efficiency for generating kb-long RNA with site-specific internal modification by a simple three-part ligation between two long RNA substrates and a modification-carrying RNA oligonucleotide. In comparison, classical splint ligation yielded a significantly lower efficiency of 0-2% in all cases. We expect that ProDAL will benefit studies involving kb-long RNAs, including translation, long non-coding RNAs, RNA splicing and modification, and large ribonucleoprotein complexes. PMID:27211284

  17. Zn(2+)-ligation DNAzyme-driven enzymatic and nonenzymatic cascades for the amplified detection of DNA.

    PubMed

    Lu, Chun-Hua; Wang, Fuan; Willner, Itamar

    2012-06-27

    A generic fluorescence sensing platform for analyzing DNA by the Zn(2+)-dependent ligation DNAzyme as amplifying biocatalyst is presented. The platform is based on the target DNA induced ligation of two substrate subunits and the subsequent opening of a beacon hairpin probe by the ligated product. The strand displacement of the ligated product by the beacon hairpin is, however, of limited efficiency. Two strategies are implemented to overcome this limitation. By one method, a "helper" nucleic acid sequence is introduced into the system, and this hybridizes with the DNAzyme components and releases the ligated product for opening of the hairpin. By the second method, a nicking enzyme (Nt.BspQI) is added to the system, and this nicks the duplex between the beacon and ligated product while recycling the free ligation product. By combining the two coadded components ("helper" sequence and nicking enzyme), the sensitive detection of the analyte is demonstrated (detection limit, 20 pM). The enzyme-free amplified fluorescence detection of the target DNA is further presented by the Zn(2+)-dependent ligation DNAzyme-driven activation of the Mg(2+)-dependent DNAzyme. According to this method, the Mg(2+)-dependent DNAzyme subunits displace the ligated product, and the resulting assembled DNAzyme cleaves a fluorophore/quencher-modified substrate to yield fluorescence. The method enabled the detection of the target DNA with a detection limit corresponding to 10 pM. The different sensing platforms are implemented to detect the Tay-Sachs genetic disorder mutant.

  18. Tubal Ligation Induces Quiescence in the Epithelia of the Fallopian Tube Fimbria.

    PubMed

    Tiourin, Ekaterina; Velasco, Victor S; Rosales, Miguel A; Sullivan, Peggy S; Janzen, Deanna M; Memarzadeh, Sanaz

    2015-10-01

    Tubal ligation keeps the fimbriated end of the fallopian tube intact while interrupting the conduit for sperm and egg between the uterus and ovary. Tubal ligation is associated with an approximately 20% decreased risk of high-grade serous ovarian cancers, which mounting evidence suggests arise from the distal fallopian tube epithelium. We postulated that biological changes at the epithelial cellular level of the distal fallopian tube may account for the surgical procedure's observed risk reduction. We compared the histology, presence of epithelial progenitors (basally located CD44-positive cells), and degree of epithelial proliferation (Ki67-positive cells) of distal fallopian tube from 10 patients with previous tubal ligation and 10 age-matched patients with uncut fallopian tubes. A significantly reduced population of proliferating epithelial progenitors (basally located CD44/Ki67 dual-positive cells) was detected in the tubal ligated specimens (P = .0002). To functionally assess the effect of tubal ligation, a murine model was utilized to compare the growth capacity of distal fallopian tube epithelial cells isolated from either ligated or sham-operated tubal epithelia. Murine fallopian tube epithelial cells isolated after tubal ligation showed a significantly reduced capacity to grow organoids in culture compared to sham-operated controls (P = .002). The findings of this study show that tubal ligation is associated with a reduced presence and decreased proliferation of progenitor cells in the distal fallopian tube epithelium. These compositional and functional changes suggest that tubal ligation induces quiescence of distal fallopian tube epithelial cells.

  19. Modified spleen stiffness measurement by transient elastography is associated with presence of large oesophageal varices in patients with compensated hepatitis C virus cirrhosis.

    PubMed

    Calvaruso, V; Bronte, F; Conte, E; Simone, F; Craxì, A; Di Marco, V

    2013-12-01

    To evaluate the accuracy of liver transient elastography (TE), spleen TE and other noninvasive tests (AAR, APRI score, platelet count, platelet/spleen ratio) in predicting the presence and the size of oesophageal varices in compensated hepatitis C virus (HCV) cirrhosis, we studied 112 consecutive patients with compensated HCV cirrhosis who underwent biochemical tests, gastrointestinal endoscopy, liver TE and spleen TE by Fibroscan(®) (Echosens, Paris, France) using a modified software version with a range between 1.5 and 150 kPa. Spleen TE was not reliable in 16 patients (14.3%). Among the 96 patients with a valid measurement (69.8% men, mean age: 63.2 ± 9.5 years), 43.7% had no oesophageal varices, 29.2% had grade 1% and 27.1% had grade 2 or grade 3 oesophageal varices. Patients with values of 75 kPa by standard spleen TE had mean values of modified spleen TE of 117 kPa (range: 81.7-149.5). Linear regression revealed a significant correlation between modified spleen TE and oesophageal varix size (r = 0.501; beta: 0.763, SE: 0.144; P < 0.001). On univariate analysis, the variables associated with grade 2/grade 3 oesophageal varices were AAR score, APRI score, platelet/spleen ratio, liver TE and modified spleen TE. On multivariate analysis, only modified spleen TE (OR: 1.026; 95% CI: 1.007-1.046; P = 0.006) and AAR (OR: 14.725; 95% CI: 1.928-112.459; P = 0.010) remained independently associated with grade 2/grade 3 oesophageal varices. Platelet/spleen ratio was the best predictor of oesophageal varices area under the ROC curve (AUROC: 0.763, cut-off: 800, sensitivity: 74%, specificity: 70%), while modified spleen TE was more accurate in predicting grade 2/grade 3 oesophageal varices (AUROC: 0.82, cut-off: 54.0 kPa, sensitivity: 80%, specificity: 70%). Portal hypertension increases spleen stiffness, and the measurement of modified spleen TE is an accurate, noninvasive tool for predicting the presence of large oesophageal varices in patients with compensated HCV

  20. Critical pitfall: varices in cancer patients mimicking lymphadenopathy; differentiation of varicose veins and enlarged lymph nodes in routine staging.

    PubMed

    Schubert, Tilman; Pansini, Michele; Bongartz, Georg; Niemann, Tilo

    2011-01-01

    Two patients, each with a history of multiple cancers, were referred to our institution for routine cancer staging. Contrast enhanced multislice-CT showed round and oval shaped inguinal and retroperitoneal masses in one patient and inguinal mass lesions in the other patient. The mass lesions were suspicious of lymphadenopathy related to cancer recurrence. Additional MR-Imaging, however, showed tortuous varicose veins as well as suspicious lymph nodes in one patient and solely venous convolutes in the other patient. Regarding the routine contrast enhanced CT-scan in the portovenous phase, varices showed no significant difference in radiodensity compared to enlarged lymph nodes.

  1. General Chemoselective and Redox-Responsive Ligation and Release Strategy

    PubMed Central

    2015-01-01

    We report a switchable redox click and cleave reaction strategy for conjugating and releasing a range of molecules on demand. This chemoselective redox-responsive ligation (CRRL) and release strategy is based on a redox switchable oxime linkage that is controlled by mild chemical or electrochemical redox signals and can be performed at physiological conditions without the use of a catalyst. Both conjugation and release reactions are kinetically well behaved and quantitative. The CRRL strategy is synthetically modular and easily monitored and characterized by routine analytical techniques. We demonstrate how the CRRL strategy can be used for the dynamic generation of cyclic peptides and the ligation of two different peptides that are stable but can be selectively cleaved upon changes in the redox environment. We also demonstrate a new redox based delivery of cargoes to live cells strategy via the CRRL methodology by synthesizing a FRET redox-responsive probe that is selectively activated within a cellular environment. We believe the ease of the CRRL strategy should find wide use in a range of applications in biology, tissue engineering, nanoscience, synthetic chemistry, and material science and will expand the suite of current conjugation and release strategies. PMID:24559434

  2. Rubber Band Ligation for Hemorrhoids: an Office Experience.

    PubMed

    Aram, Fahmi Omer

    2016-08-01

    The objective of this study was to analyze the effectiveness, safety, quality of life, and the results of the treatment for second- and third-degree hemorrhoids using rubber band ligation (RBL). This is a retrospective study for 890 patients who came to outpatient clinic from August 2007 to March 2013; all underwent rubber band ligation using the Barron applicator on an outpatient basis for second- and third-degree internal symptomatic hemorrhoids. Data were collected from the patients' files. The patients were asked to return to outpatient clinic for follow-up at 2 weeks and 1 and 6 months and by telephone call every 6 months for 2 years. Six hundred seventy-seven patients (76 %) were cured (P = 0.31). Symptomatic recurrence was detected in 178 cases (20 %) after 2 years. Thirty-five patients (4 %) had some complications from RBL, which required no hospitalization. The complications were pain, rectal bleeding, and vasovagal symptoms (2.6, 1, and 0.4 % of patients, respectively). Seven hundred fifty-six (85 %) of the patients are males; the mean age was 45 years (range, 16-86 years). RBL is a simple, safe, and effective method for treating symptomatic second- and third-degree hemorrhoids as an outpatient procedure with significant improvement in quality of life. PMID:27574343

  3. PECAM-1 ligation negatively regulates TLR4 signaling in macrophages.

    PubMed

    Rui, Yuxiang; Liu, Xingguang; Li, Nan; Jiang, Yingming; Chen, Guoyou; Cao, Xuetao; Wang, Jianli

    2007-12-01

    Uncontrolled TLR4 signaling may induce excessive production of proinflammatory cytokines and lead to harmful inflammation; therefore, negative regulation of TLR4 signaling attracts much attention now. PECAM-1, a member of Ig-ITIM family, can mediate inhibitory signals in T cells and B cells. However, the role and the mechanisms of PECAM-1 in the regulation of TLR4-mediated LPS response in macrophages remain unclear. In this study, we demonstrate that PECAM-1 ligation with CD38-Fc fusion protein negatively regulates LPS-induced proinflammatory cytokine TNF-alpha, IL-6, and IFN-beta production by inhibiting JNK, NF-kappaB, and IFN regulatory factor 3 activation in macrophages. In addition, PECAM-1 ligation-recruited Src homology region 2 domain-containing phosphatase 1 (SHP-1) and Src homology region 2 domain-containing phosphatase 2 (SHP-2) may be involved in the inhibitory effect of PECAM-1 on TLR4 signaling. Consistently, silencing of PECAM-1 enhances the macrophage response to LPS stimulation. Taken together with the data that PECAM-1 is constitutively expressed in macrophages and its expression is up-regulated by LPS stimulation, PECAM-1 might function as a feedback negative regulator of LPS inflammatory response in macrophages. This study may provide a potential target for intervention of inflammatory diseases. PMID:18025177

  4. Binding-regulated click ligation for selective detection of proteins.

    PubMed

    Cao, Ya; Han, Peng; Wang, Zhuxin; Chen, Weiwei; Shu, Yongqian; Xiang, Yang

    2016-04-15

    Herein, a binding-regulated click ligation (BRCL) strategy for endowing selective detection of proteins is developed with the incorporation of small-molecule ligand and clickable DNA probes. The fundamental principle underlying the strategy is the regulating capability of specific protein-ligand binding against the ligation between clickable DNA probes, which could efficiently combine the detection of particular protein with enormous DNA-based sensing technologies. In this work, the feasibly of the BRCL strategy is first verified through agarose gel electrophoresis and electrochemical impedance spectroscopy measurements, and then confirmed by transferring it to a nanomaterial-assisted fluorescence assay. Significantly, the BRCL strategy-based assay is able to respond to target protein with desirable selectivity, attributing to the specific recognition between small-molecule ligand and its target. Further experiments validate the general applicability of the sensing method by tailoring the ligand toward different proteins (i.e., avidin and folate receptor), and demonstrate its usability in complex biological samples. To our knowledge, this work pioneers the practice of click chemistry in probing specific small-molecule ligand-protein binding, and therefore may pave a new way for selective detection of proteins.

  5. Periodontal effects with self ligating appliances and laser biostimulation

    PubMed Central

    Caccianiga, Gianluigi; Cordasco, Giancarlo; Leonida, Alessandro; Zorzella, Paolo; Squarzoni, Nadia; Carinci, Francesco; Crestale, Claudia

    2012-01-01

    Background: Recently, various biostimulation's effects of low energy laser irradiation have been reported. The present study was designed to examine the effects of low-energy laser irradiation on alveolar bone remodelling during orthodontic tooth movement and finally on formation of new keratinized gingiva. Materials and Methods: 22 patients and 27 teeth in vestibular mucosal without keratinized gingiva were selected. Every patient was treated with self ligating appliances. In every orthodontic session the patient was treated with Diode laser biostimulation. At the moment of debonding, 27 teeth involved in the research were evaluated in terms of quality and quantity of attached gingiva. BOP and CAL loss were investigated. Results: Every tooth considered at the end of orthodontic treatment showed an attached gingiva around the crown: The average of keratinized gingiva at the end of the study was 3.10 mm and the mean increasing at each month was 0,49 mm. Conclusions: The combination between self ligating appliances and laser's biostimulation could improve the differentiation of periodontal ligaments stem cells in fibroblasts, able to promote attached gingiva around the crown of the teeth erupted in oral vestibular mucosa. PMID:23814581

  6. TLR9 ligation in pancreatic stellate cells promotes tumorigenesis

    PubMed Central

    Zambirinis, Constantinos P.; Levie, Elliot; Nguy, Susanna; Avanzi, Antonina; Barilla, Rocky; Xu, Yijie; Seifert, Lena; Daley, Donnele; Greco, Stephanie H.; Deutsch, Michael; Jonnadula, Saikiran; Torres-Hernandez, Alejandro; Tippens, Daniel; Pushalkar, Smruti; Eisenthal, Andrew; Saxena, Deepak; Ahn, Jiyoung; Hajdu, Cristina; Engle, Dannielle D.; Tuveson, David

    2015-01-01

    Modulation of Toll-like receptor (TLR) signaling can have protective or protumorigenic effects on oncogenesis depending on the cancer subtype and on specific inflammatory elements within the tumor milieu. We found that TLR9 is widely expressed early during the course of pancreatic transformation and that TLR9 ligands are ubiquitous within the tumor microenvironment. TLR9 ligation markedly accelerates oncogenesis, whereas TLR9 deletion is protective. We show that TLR9 activation has distinct effects on the epithelial, inflammatory, and fibrogenic cellular subsets in pancreatic carcinoma and plays a central role in cross talk between these compartments. Specifically, TLR9 activation can induce proinflammatory signaling in transformed epithelial cells, but does not elicit oncogene expression or cancer cell proliferation. Conversely, TLR9 ligation induces pancreatic stellate cells (PSCs) to become fibrogenic and secrete chemokines that promote epithelial cell proliferation. TLR9-activated PSCs mediate their protumorigenic effects on the epithelial compartment via CCL11. Additionally, TLR9 has immune-suppressive effects in the tumor microenvironment (TME) via induction of regulatory T cell recruitment and myeloid-derived suppressor cell proliferation. Collectively, our work shows that TLR9 has protumorigenic effects in pancreatic carcinoma which are distinct from its influence in extrapancreatic malignancies and from the mechanistic effects of other TLRs on pancreatic oncogenesis. PMID:26481685

  7. Management of non-variceal upper gastrointestinal tract hemorrhage: controversies and areas of uncertainty.

    PubMed

    Trawick, Eric P; Yachimski, Patrick S

    2012-03-21

    Upper gastrointestinal tract hemorrhage (UGIH) remains a common presentation requiring urgent evaluation and treatment. Accurate assessment, appropriate intervention and apt clinical skills are needed for proper management from time of presentation to discharge. The advent of pharmacologic acid suppression, endoscopic hemostatic techniques, and recognition of Helicobacter pylori as an etiologic agent in peptic ulcer disease (PUD) has revolutionized the treatment of UGIH. Despite this, acute UGIH still carries considerable rates of morbidity and mortality. This review aims to discuss current areas of uncertainty and controversy in the management of UGIH. Neoadjuvant proton pump inhibitor (PPI) therapy has become standard empiric treatment for UGIH given that PUD is the leading cause of non-variceal UGIH, and PPIs are extremely effective at promoting ulcer healing. However, neoadjuvant PPI administration has not been shown to affect hard clinical outcomes such as rebleeding or mortality. The optimal timing of upper endoscopy in UGIH is often debated. Upon completion of volume resuscitation and hemodynamic stabilization, upper endoscopy should be performed within 24 h in all patients with evidence of UGIH for both diagnostic and therapeutic purposes. With rising healthcare cost paramount in today's medical landscape, the ability to appropriately triage UGIH patients is of increasing value. Upper endoscopy in conjunction with the clinical scenario allows for accurate decision making concerning early discharge home in low-risk lesions or admission for further monitoring and treatment in higher-risk lesions. Concomitant pharmacotherapy with non-steroidal anti-inflammatory drugs (NSAIDs) and antiplatelet agents, such as clopidogrel, has a major impact on the etiology, severity, and potential treatment of UGIH. Long-term PPI use in patients taking chronic NSAIDs or clopidogrel is discussed thoroughly in this review. PMID:22468078

  8. Aspirin use for primary prophylaxis: Adverse outcomes in non-variceal upper gastrointestinal bleeding

    PubMed Central

    Souk, Karina M; Tamim, Hani M; Abu Daya, Hussein A; Rockey, Don C; Barada, Kassem A

    2016-01-01

    AIM: To compare outcomes of patients with non-variceal upper gastrointestinal bleeding (NVUGIB) taking aspirin for primary prophylaxis to those not taking it. METHODS: Patients not known to have any vascular disease (coronary artery or cerebrovascular disease) who were admitted to the American University of Beirut Medical Center between 1993 and 2010 with NVUGIB were included. The frequencies of in-hospital mortality, re-bleeding, severe bleeding, need for surgery or embolization, and of a composite outcome defined as the occurrence of any of the 4 bleeding related adverse outcomes were compared between patients receiving aspirin and those on no antithrombotics. We also compared frequency of in hospital complications and length of hospital stay between the two groups. RESULTS: Of 357 eligible patients, 94 were on aspirin and 263 patients were on no antithrombotics (control group). Patients in the aspirin group were older, the mean age was 58 years in controls and 67 years in the aspirin group (P < 0.001). Patients in the aspirin group had significantly more co-morbidities, including diabetes mellitus and hypertension [25 (27%) vs 31 (112%) and 44 (47%) vs 74 (28%) respectively, (P = 0.001)], as well as dyslipidemia [21 (22%) vs 16 (6%), P < 0.0001). Smoking was more frequent in the aspirin group [34 (41%) vs 60 (27%), P = 0.02)]. The frequencies of endoscopic therapy and surgery were similar in both groups. Patients who were on aspirin had lower in-hospital mortality rates (2.1% vs 13.7%, P = 0.002), shorter hospital stay (4.9 d vs 7 d, P = 0.01), and fewer composite outcomes (10.6% vs 24%, P = 0.01). The frequencies of in-hospital complications and re-bleeding were similar in the two groups. CONCLUSION: Patients who present with NVUGIB while receiving aspirin for primary prophylaxis had fewer adverse outcomes. Thus aspirin may have a protective effect beyond its cardiovascular benefits. PMID:27462392

  9. [Laparoscopic ligation of the internal iliac artery in bleeding cervix carcinoma].

    PubMed

    Skret, A; Obrzut, B; Stachurski, J

    1995-01-01

    Laparoscopic ligation of internal iliac artery was performed in two patients with bleeding from stage II cervical cancer. The hemostatic effect, shortening of convalescence and early initiation of radiotherapy was obtained. Additionally, during procedure the lymph node sampling was performed. Laparoscopy appeared to be an alternative procedure to abdominal or extraperitoneal ligation of internal iliac artery. PMID:7483884

  10. The effect of bracket type and ligation method upon forces exerted by orthodontic archwires.

    PubMed

    Rock, W P; Wilson, H J

    1989-08-01

    The effects of bracket type and ligation method upon the forces exerted at 1.5-mm deflection by three archwire materials were measured in a simulated clinical situation. Significant force differences were found when archwires were used in standard edgewise or straightwire brackets, respectively, and also when Alastik modules were used for ligation instead of steel ligatures.

  11. Ligation of the hairpin ribozyme in cis induced by freezing and dehydration

    PubMed Central

    KAZAKOV, SERGEI A.; BALATSKAYA, SVETLANA V.; JOHNSTON, BRIAN H.

    2006-01-01

    Although reducing the temperature slows most chemical reactions, freezing can stimulate some reactions by mechanisms that are only partially understood. Here we show that freezing stimulates the self-ligation (circularization) of linear forms of the hairpin ribozyme (HPR) containing 2′,3′-cyclic phosphate and 5′-OH termini. Divalent metal ions (M2+) are not required, but monovalent cations and anions at millimolar concentrations can have various effects on this reaction depending on the specific ion. Under optimal conditions, the observed rate of M2+-independent self-ligation reaches a peak (0.04 min−1) at −10°C with a yield of −60% after 1 h. In contrast, no ligation occurs either at above 0°C or in solutions that remain unfrozen when supercooled to subzero temperatures. Under freezing conditions, the cleavage–ligation equilibrium strongly favors ligation. Besides freezing, evaporation of the aqueous solvent as well as the presence of ethanol at levels of 40% or above can also induce M2+-independent HPR ligation at 25°C. We argue that partial RNA dehydration, which is a common feature of freezing, evaporation, and the presence of ethanol, is a key factor supporting HPR ligation activity at both above- and below-freezing temperatures. In the context of the RNA world hypothesis, freezing-induced ligation is an attractive mechanism by which complex RNAs could have evolved under conditions in which RNA was relatively protected against degradation. PMID:16495237

  12. Traditional elastic ligatures versus slide ligation system. A morphological evaluation

    PubMed Central

    CONDÒ, R.; CASAGLIA, A.; ARMELLIN, E.; CONDÒ, S.G.; CERRONI, L.

    2013-01-01

    SUMMARY Objective Elastomeric materials play an important role in the orthodontic practice, including the retraction force to move teeth into extraction sites, closing diastemas, selective shifting of the midline and generalized space closure. Frictional resistance and ligating strength of archwire-bracket-ligature complex occurs during utilization of elastomeric and metallic ligatures when orthodontic forces are applicated. The aim of this study was to analyze elastic deformation of three types of elastomeric ligatures, after clinical use. Material and Methods Elastomeric ligatures: ring-shape, transparent, latex ligatures (Leone® S.p.A.), ring-shape, grey, polyurethane ligatures (Micerium® S.p.A.) and grey, polyurethane, Slide low-friction ligatures (Leone® S.p.A.). A total of 9 orthodontic patients undergoing fixed orthodontic therapy were selected. Three specimens were applied, one for each types of ligature, inside the oral cavity of each subject. Samples were kept in the oral cavity for 28 days, ligating 0.16 X 0.22 inches stainless steel archwires to stainless steel premolars brackets (Leone® S.p.A., Sesto Fiorentino, FI, Italy) for Bidimensional technique. After the pre-established time, the systems of ligature were removed and washed. Control group consisted of 9 unused specimens of each ligation type. Each elastomeric ligature was observed under the scanning electron microscope (SEM) to determine variations in size. The archwire-bracket-ligature complex was also analyzed. Results Transparent O-ring ligatures showed significant volumetric and structural changes. The external rounded shape was rather maintained, while the internal shape tended to appear square. Both external and internal diameter significantly increased (p<0.005 and p<0.0001 respectively) while the thickness decreased ( p<0,005) when analyzed with t-test. Polyurethane ring-shape ligatures retained the initial ring design. Both external and internal diameter increased (p<0.0001), while

  13. Comparison of microcoils and polyvinyl alcohol particles in selective microcatheter angioembolization of non variceal acute gastrointestinal hemorrhage

    PubMed Central

    Tanveer-Ul-Haq; Idris, Muhammad; Salam, Basit; Akhtar, Waseem; Jamil, Yasir

    2015-01-01

    Objectives: To compare the efficacy of polyvinyl alcohol (PVA) particles with microcoils in angiembolisation of non variceal acute gastrointestinal haemorrhage. Methods: This is a retrospective cross-sectional study of patients who underwent transcatheter angioembolization from January, 1995 to December, 2013 at Aga Khan University Hospital, Karachi. Patients were divided into two groups on basis of use of either microcoils or PVA particles and compared in terms of technical success, clinical success, re-bleeding and ischemic complication rates. Chi (χ2) square and Fisher’s exact tests were applied and a P-value of less than 0.05 was considered statistically significant. Results: Fifty seven patients underwent angioembolization. Microcoil and PVA particles embolization was performed in 63% (36/57) and 35% (20/57) cases respectively. Technical success was achieved in all cases (100%). Clinical success rate was higher in microcoils group (92%) than PVA particles group (75%) with statistically significant P value (p=0.048). Ischemic complication was seen in one case (3%) in the microcoil group, while no such complications were seen in the PVA particles group. Conclusion: In angioembolization of non variceal acute gastrointestinal haemorrhage microcoils are better than Polyvinyl alcohol particles with higher clinical success and lower re-bleed rates. PMID:26430397

  14. Torsade de pointes complicating the treatment of bleeding esophageal varices: association with neuroleptics, vasopressin, and electrolyte imbalance.

    PubMed

    Faigel, D O; Metz, D C; Kochman, M L

    1995-05-01

    Torsade de pointes is an unusual life-threatening ventricular arrhythmia that has been associated with vasopressin, neuroleptic drugs, and electrolyte imbalances, including hypokalemia and hypomagnesemia. Over a 9-month period, we observed torsade de pointes in three patients with cirrhosis and bleeding esophageal varices who did not have prior cardiac disease. All had received endoscopic sclerotherapy and continuous infusions of vasopressin and nitroglycerin. For sedation, two patients received haloperidol and one droperidol. In addition, two patients had either hypokalemia or hypomagnesemia. In all three patients, there was prolongation of the electrocardiographic QT interval and a "long-short" initiating sequence followed by ventricular tachycardia with torsade de pointes morphology. All were successfully cardioverted; there was one late death due to aspiration and septicemia. We conclude that cirrhotics with variceal hemorrhage may be at increased risk of developing this arrhythmia in the setting of treatment with vasopressin, sedation with neuroleptic drugs, and electrolyte abnormalities. We urge close monitoring of these patients for cardiac arrhythmia and recommend that neuroleptics be used cautiously, if at all.

  15. Repeated pancreatitis-induced splenic vein thrombosis leads to intractable gastric variceal bleeding: A case report and review

    PubMed Central

    Tang, Shan-Hong; Zeng, Wei-Zheng; He, Qian-Wen; Qin, Jian-Ping; Wu, Xiao-Ling; Wang, Tao; Wang, Zhao; He, Xuan; Zhou, Xiao-Lei; Fan, Quan-Shui; Jiang, Ming-De

    2015-01-01

    Gastric varices (GV) are one of the most common complications for patients with portal hypertension. Currently, histoacryl injection is recommended as the initial treatment for bleeding of GV, and this injection has been confirmed to be highly effective for most patients in many studies. However, this treatment might be ineffective for some types of GV, such as splenic vein thrombosis-related localized portal hypertension (also called left-sided, sinistral, or regional portal hypertension). Herein, we report a case of repeated pancreatitis-induced complete splenic vein thrombosis that led to intractable gastric variceal bleeding, which was treated by splenectomy. We present detailed radiological and pathological data and blood rheology analysis (the splenic artery - after a short gastric vein or stomach vein - gastric coronary vein - portal vein). The pathophysiology can be explained by the abnormal direction of blood flow in this patient. To our knowledge, this is the first reported case for which detailed pathology and blood rheology data are available. PMID:26488031

  16. Safety and efficacy of 2-octyl-cyanoacrylate in the management of patients with gastric and duodenal varices who are not candidates for transjugular intrahepatic portosystemic shunts

    PubMed Central

    Burdick, James; Trotter, James F.

    2016-01-01

    Gastric variceal bleeding is associated with significant morbidity and mortality in patients with portal hypertension and cirrhosis. Options are limited for patients who are not candidates for transjugular intrahepatic portosystemic shunts (TIPS). Cyanoacrylate injections have been reported to be efficacious in previous case series. The aim of this retrospective study was to report our single-center experience with the safety and efficacy of 2-octyl-cyanoacrylate in patients who were not TIPS candidates. Electronic medical records were reviewed for 16 patients who underwent a total of 18 esophagogastroduodenoscopies for acute gastric or duodenal variceal bleeding and secondary prophylaxis of gastric varices; 14 patients had cirrhosis with an average Model for End-Stage Liver Disease score of 16, and 2 patients had noncirrhotic portal hypertension. Primary endpoints of the study included early and delayed rebleeding rate, complications, and death or liver transplantation. The rebleeding rate (early or delayed) was 7%, and no complications were found. One death was reported (unrelated to the procedure). In conclusion, 2-octyl-cyanoacrylate is a safe and effective alternative for non-TIPS candidates who present with acute gastric variceal bleeding given its low rebleeding and complication rate. PMID:27695164

  17. Successful use of a transjugular intrahepatic portosystemic stent shunt to control severe refractory oesophageal variceal haemorrhage in a poor risk patient.

    PubMed Central

    Beales, I. L.; Jackson, J. E.; Rudolf, M.; Arnold, J.

    1993-01-01

    This report describes a 44 year old man with a severe gastrointestinal haemorrhage from oesophageal varices. Bleeding could not be controlled with conservative therapy and sclerotherapy. He was successfully treated with a radiologically guided transjugular intrahepatic stent shunt at a time when his condition was too poor to attempt an open surgical procedure. PMID:8121873

  18. Safety and efficacy of 2-octyl-cyanoacrylate in the management of patients with gastric and duodenal varices who are not candidates for transjugular intrahepatic portosystemic shunts

    PubMed Central

    Burdick, James; Trotter, James F.

    2016-01-01

    Gastric variceal bleeding is associated with significant morbidity and mortality in patients with portal hypertension and cirrhosis. Options are limited for patients who are not candidates for transjugular intrahepatic portosystemic shunts (TIPS). Cyanoacrylate injections have been reported to be efficacious in previous case series. The aim of this retrospective study was to report our single-center experience with the safety and efficacy of 2-octyl-cyanoacrylate in patients who were not TIPS candidates. Electronic medical records were reviewed for 16 patients who underwent a total of 18 esophagogastroduodenoscopies for acute gastric or duodenal variceal bleeding and secondary prophylaxis of gastric varices; 14 patients had cirrhosis with an average Model for End-Stage Liver Disease score of 16, and 2 patients had noncirrhotic portal hypertension. Primary endpoints of the study included early and delayed rebleeding rate, complications, and death or liver transplantation. The rebleeding rate (early or delayed) was 7%, and no complications were found. One death was reported (unrelated to the procedure). In conclusion, 2-octyl-cyanoacrylate is a safe and effective alternative for non-TIPS candidates who present with acute gastric variceal bleeding given its low rebleeding and complication rate.

  19. [Glypressin and emergency sclerotherapy, deferred emergency shunt (Warren, portacaval, mesocaval): new tactics in the treatment of severe hemorrhage by esophagogastric varices in cirrhotic patients].

    PubMed

    Huscher, C; Biraghi, M; Chiodini, S; Recher, A; Torri, F; Zamboni, F

    1990-01-01

    Transplenic decompression of esophageal varices by distal splenorenal shunt according to Warren (DSRS) aims to a selective detention of the esophago-gastric varices, also assuring an adequate portal perfusion and hypertensive state of the porto-mesenteric district. The DSRS though, should and must not be performed in emergency as a high mortality rate is registered in all cases of emergency porto-systemic derivations. A mortality risk is reported even during endoscopic sclerosis if performed in emergency compared to the elective procedure. The scope of our study was to test the validity of a new approach of the hemorrhagic cirrhotic patient: the end point was to stop the bleeding with Glypressin and deferred sclerotherapy, associating a selective shunt at 40-60 days. Out of 32 patients with esophago-gastric variceal bleeding, 8 were selected also for derivative surgery. Results show Glypressin as the first and best therapeutic approach. The drug in many cases stops bleeding or at least reduces the blood loss allowing an easier endoscopic sclerosis. Further sclerosis and/or surgical therapy may assure variceal eradication.

  20. Detection of Protein SUMOylation In Situ by Proximity Ligation Assays.

    PubMed

    Sahin, Umut; Jollivet, Florence; Berthier, Caroline; de Thé, Hugues; Lallemand-Breitenbach, Valérie

    2016-01-01

    Sumoylation is a posttranslational process essential for life and concerns a growing number of crucial proteins. Understanding the influence of this phenomenon on individual proteins or on cellular pathways in which they function has become an intense area of research. A critical step in studying protein sumoylation is to detect sumoylated forms of a particular protein. This has proven to be a challenging task for a number of reasons, especially in the case of endogenous proteins and in vivo studies or when studying rare cells such as stem cells. Proximity ligation assays that allow detection of closely interacting protein partners can be adapted for initial detection of endogenous sumoylation or ubiquitination in a rapid, ultrasensitive, and cheap manner. In addition, modified forms of a given protein can be detected in situ in various cellular compartments. Finally, the flexibility of this technique may allow rapid screening of drugs and stress signals that may modulate protein sumoylation. PMID:27631803

  1. Bioorthogonal Oxime Ligation Mediated In Vivo Cancer Targeting

    PubMed Central

    Tang, Li; Yin, Qian; Xu, Yunxiang; Zhou, Qin; Cai, Kaimin; Yen, Jonathan; Dobrucki, Lawrence W.

    2015-01-01

    Current cancer targeting relying on specific biological interaction between cell surface antigen and respective antibody or its analogue has proven to be effective in the treatment of different cancers; however, this strategy has its own limitations, such as heterogeneity of cancer cells and immunogenicity of the biomacromolecule binding ligands. Bioorthogonal chemical conjugation has emerged as an attractive alternative to biological interaction for in vivo cancer targeting. Here, we report an in vivo cancer targeting strategy mediated by bioorthogonal oxime ligation. Oxyamine group, the artificial target, is introduced onto 4T1 murine breast cancer cells through liposome delivery and fusion. Poly(ethylene glycol) -polylactide (PEG-PLA) nanoparticle (NP) is surface-functionalized with aldehyde groups as targeting ligands. The improved in vivo cancer targeting of PEG-PLA NPs is achieved through specific and efficient chemical reaction between the oxyamine and aldehyde groups. PMID:26146536

  2. A ligation-independent cloning method using nicking DNA endonuclease.

    PubMed

    Yang, Jie; Zhang, Zhihong; Zhang, Xin A; Luo, Qingming

    2010-11-01

    Using nicking DNA endonuclease (NiDE), we developed a novel technique to clone DNA fragments into plasmids. We created a NiDE cassette consisting of two inverted NiDE substrate sites sandwiching an asymmetric four-base sequence, and NiDE cleavage resulted in 14-base single-stranded termini at both ends of the vector and insert. This method can therefore be used as a ligation-independent cloning strategy to generate recombinant constructs rapidly. In addition, we designed and constructed a simple and specific vector from an Escherichia coli plasmid back-bone to complement this cloning method. By cloning cDNAs into this modified vector, we confirmed the predicted feasibility and applicability of this cloning method. PMID:21091446

  3. Confinement-induced Molecular Templating and Controlled Ligation

    NASA Astrophysics Data System (ADS)

    Berard, Daniel; Shayegan, Marjan; Michaud, François; Henkin, Gil; Scott, Shane; Leith, Jason; Leslie, Sabrina; Leslie Lab Team

    Loading and manipulating long DNA molecules within sub-50 nm cross-section nanostructures for genomic and biochemical analyses, while retaining their structural integrity, present key technological challenges to the biotechnology sector, such as device clogging and molecular breakage. We overcome these challenges by using Convex Lens-induced Confinement (CLiC) technology to gently load DNA into nanogrooves from above. Here, we demonstrate single-fluorophore visualization of custom DNA barcodes as well as efficient top-loading of DNA into sub-50 nm nanogrooves of variable topographies. We study confinement-enhanced self-ligation of polymers loaded in circular nanogrooves. Further, we use concentric, circular nanogrooves to eliminate confinement gradient-induced drift of stretched DNA.

  4. Sensitive detection of aggregated prion protein via proximity ligation.

    PubMed

    Hammond, Maria; Wik, Lotta; Deslys, Jean-Philippe; Comoy, Emmanuel; Linné, Tommy; Landegren, Ulf; Kamali-Moghaddam, Masood

    2014-01-01

    The DNA assisted solid-phase proximity ligation assay (SP-PLA) provides a unique opportunity to specifically detect prion protein (PrP) aggregates by investigating the collocation of 3 or more copies of the specific protein. We have developed an SP-PLA that can detect PrP aggregates in brain homogenates from infected hamsters even after a 10(7)-fold dilution. In contrast, brain homogenate from uninfected animals did not generate a detectable signal at 100-fold higher concentration. Using either of the 2 monoclonal anti-PrP antibodies, 3F4 and 6H4, we successfully detected low concentrations of aggregated PrP. The presented results provide a proof of concept that this method might be an interesting tool in the development of diagnostic approaches of prion diseases.

  5. Detection of Protein SUMOylation In Situ by Proximity Ligation Assays.

    PubMed

    Sahin, Umut; Jollivet, Florence; Berthier, Caroline; de Thé, Hugues; Lallemand-Breitenbach, Valérie

    2016-01-01

    Sumoylation is a posttranslational process essential for life and concerns a growing number of crucial proteins. Understanding the influence of this phenomenon on individual proteins or on cellular pathways in which they function has become an intense area of research. A critical step in studying protein sumoylation is to detect sumoylated forms of a particular protein. This has proven to be a challenging task for a number of reasons, especially in the case of endogenous proteins and in vivo studies or when studying rare cells such as stem cells. Proximity ligation assays that allow detection of closely interacting protein partners can be adapted for initial detection of endogenous sumoylation or ubiquitination in a rapid, ultrasensitive, and cheap manner. In addition, modified forms of a given protein can be detected in situ in various cellular compartments. Finally, the flexibility of this technique may allow rapid screening of drugs and stress signals that may modulate protein sumoylation.

  6. Left Atrial Appendage Ligation and Exclusion Technology in the Incubator

    PubMed Central

    Syed, Faisal F.; Noheria, Amit; DeSimone, Christopher V.; Asirvatham, Samuel J.

    2016-01-01

    Stroke is the most feared complication of atrial fibrillation (AF). Targeting the left atrial appendage (LAA) mechanically is attractive as a means to simultaneously reduce stroke risk, the need for anticoagulation, and hemorrhagic complications in patients with non-valvular AF. The results of the PROTECT-AF and PREVAIL randomized clinical trials support this approach as a viable therapeutic alternative to warfarin in selected patients and add to accumulating evidence regarding the importance of the LAA in thromboembolism in AF. A number of devices for percutaneous LAA closure are under investigation or development. In this article, key design features of these ligation and exclusion technologies will be discussed, with a focus on aspects of LAA morphology, relational anatomy, thrombosis, and thromboembolism relevant for successful device development and deployment. PMID:27087888

  7. In vivo multiphoton imaging of bile duct ligation

    NASA Astrophysics Data System (ADS)

    Liu, Yuan; Li, Feng-Chieh; Chen, Hsiao-Chin; Chang, Po-shou; Yang, Shu-Mei; Lee, Hsuan-Shu; Dong, Chen-Yuan

    2008-02-01

    Bile is the exocrine secretion of liver and synthesized by hepatocytes. It is drained into duodenum for the function of digestion or drained into gallbladder for of storage. Bile duct obstruction is a blockage in the tubes that carry bile to the gallbladder and small intestine. However, Bile duct ligation results in the changes of bile acids in serum, liver, urine, and feces1, 2. In this work, we demonstrate a novel technique to image this pathological condition by using a newly developed in vivo imaging system, which includes multiphoton microscopy and intravital hepatic imaging chamber. The images we acquired demonstrate the uptake, processing of 6-CFDA in hepatocytes and excretion of CF in the bile canaliculi. In addition to imaging, we can also measure kinetics of the green fluorescence intensity.

  8. Usefulness of intra-procedural cone-beam computed tomography in modified balloon-occluded retrograde transvenous obliteration of gastric varices

    PubMed Central

    Lee, Edward Wolfgang; So, Naomi; Chapman, Ryan; McWilliams, Justin P; Loh, Christopher T; Busuttil, Ronald W; Kee, Stephen T

    2016-01-01

    AIM: To evaluate whether intra-procedural cone-beam computed tomography (CBCT) performed during modified balloon-occluded retrograde transvenous obliteration (mBRTO) can accurately determine technical success of complete variceal obliteration. METHODS: From June 2012 to December 2014, 15 patients who received CBCT during mBRTO for treatment of portal hypertensive gastric variceal bleeding were retrospectively evaluated. Three-dimensional (3D) CBCT images were performed and evaluated prior to the end of the procedure, and these were further analyzed and compared to the pre-procedure contrast-enhanced computed tomography to determine the technical success of mBRTO including: Complete occlusion/obliteration of: (1) gastrorenal shunt (GRS); (2) gastric varices; and (3) afferent feeding veins. Post-mBRTO contrast-enhanced CT was used to confirm the accuracy and diagnostic value of CBCT within 2-3 d. RESULTS: Intra-procedural 3D-CBCT images were 100% accurate in determining the technical success of mBRTO in all 15 cases. CBCT demonstrated complete occlusion/obliteration of GRS, gastric varices, collaterals and afferent feeding veins during mBRTO, which was confirmed with post-mBRTO CT. Two patients showed incomplete obliteration of gastric varices and feeding veins on CBCT, which therefore required additional gelfoam injections to complete the procedure. No patient required additional procedures or other interventions during their follow-up period (684 ± 279 d). CONCLUSION: CBCT during mBRTO appears to accurately and immediately determine the technical success of mBRTO. This may improve the technical and clinical success/outcome of mBRTO and reduce additional procedure time in the future. PMID:27158425

  9. Evaluation of Micro-organism in Ligated Metal and Self-ligating Brackets using Scanning Electron Microscopy: An In Vivo Study

    PubMed Central

    Sunil, P C; Michael, Tony; Raju, Aravind S; Paul, Renji K; Mamatha, J; Ebin, T M

    2015-01-01

    Background: The objective of the study was to determine the sites of plaque accumulation and to compare the plaque accumulated with metal and self-ligating orthodontic brackets in order to know which bracket type had a higher plaque retaining capacity. Materials and Methods: The study was done on 20 subjects who were scheduled for orthodontic treatment including extraction of four premolars and fixed orthodontic appliances. Mesh-backed edgewise metal brackets ligated with steel ligatures and self-ligating brackets were bonded to the premolars to be extracted using composite (Transbond XT, 3M). The subjects were told to continue their normal oral hygiene regimen. Teeth were extracted at 1, 2, and 3 weeks after bracket bonding. Plaque attached to the buccal surfaces was stained using plaque disclosing agent. The teeth were then immersed in fixative containing 4% formaldehyde and 1% glutaraldehyde in phosphate buffer for 24 h, followed by 0.1 M phosphate buffer for 12 h. The specimens were then mounted on aluminum stubs, and sputter coated with gold prior to Scanning electron microscopy examination. Results: The results showed that increased retention of plaque in metal brackets ligated with steel ligatures and comparatively less in self-ligating brackets at the base of the brackets. Conclusions: This study highlights that higher retention of plaque in metal brackets ligated with steel ligatures and comparatively less plaque retention in self-ligating brackets. Excess composite around the bracket base is the critical site of plaque accumulation associated with fixed appliances due to its rough surface texture. PMID:26229372

  10. Protein synthesis by native chemical ligation: Expanded scope by using straightforward methodology

    PubMed Central

    Hackeng, Tilman M.; Griffin, John H.; Dawson, Philip E.

    1999-01-01

    The total chemical synthesis of proteins has great potential for increasing our understanding of the molecular basis of protein function. The introduction of native chemical ligation techniques to join unprotected peptides next to a cysteine residue has greatly facilitated the synthesis of proteins of moderate size. Here, we describe a straightforward methodology that has enabled us to rapidly analyze the compatibility of the native chemical ligation strategy for X–Cys ligation sites, where X is any of the 20 naturally occurring amino acids. The simplified methodology avoids the necessity of specific amino acid thioester linkers or alkylation of C-terminal thioacid peptides. Experiments using matrix-assisted laser-desorption ionization MS analysis of combinatorial ligations of LYRAX-C-terminal thioester peptides to the peptide CRANK show that all 20 amino acids are suitable for ligation, with Val, Ile, and Pro representing less favorable choices because of slow ligation rates. To illustrate the method’s utility, two 124-aa proteins were manually synthesized by using a three-step, four-piece ligation to yield a fully active human secretory phospholipase A2 and a catalytically inactive analog. The combination of flexibility in design with general access because of simplified methodology broadens the applicability and versatility of chemical protein synthesis. PMID:10468563

  11. Recursive directional ligation by plasmid reconstruction allows rapid and seamless cloning of oligomeric genes.

    PubMed

    McDaniel, Jonathan R; Mackay, J Andrew; Quiroz, Felipe García; Chilkoti, Ashutosh

    2010-04-12

    This paper reports a new strategy, recursive directional ligation by plasmid reconstruction (PRe-RDL), to rapidly clone highly repetitive polypeptides of any sequence and specified length over a large range of molecular weights. In a single cycle of PRe-RDL, two halves of a parent plasmid, each containing a copy of an oligomer, are ligated together, thereby dimerizing the oligomer and reconstituting a functional plasmid. This process is carried out recursively to assemble an oligomeric gene with the desired number of repeats. PRe-RDL has several unique features that stem from the use of type IIs restriction endonucleases: first, PRe-RDL is a seamless cloning method that leaves no extraneous nucleotides at the ligation junction. Because it uses type IIs endonucleases to ligate the two halves of the plasmid, PRe-RDL also addresses the major limitation of RDL in that it abolishes any restriction on the gene sequence that can be oligomerized. The reconstitution of a functional plasmid only upon successful ligation in PRe-RDL also addresses two other limitations of RDL: the significant background from self-ligation of the vector observed in RDL, and the decreased efficiency of ligation due to nonproductive circularization of the insert. PRe-RDL can also be used to assemble genes that encode different sequences in a predetermined order to encode block copolymers or append leader and trailer peptide sequences to the oligomerized gene. PMID:20184309

  12. Kinetic and mechanistic analysis of nonenzymatic, template-directed oligoribonucleotide ligation

    NASA Technical Reports Server (NTRS)

    Rohatgi, R.; Bartel, D. P.; Szostak, J. W.

    1996-01-01

    The role of divalent cations in the mechanism of pyrophosphate-activated, template-directed oligoribonucleotide ligation has been investigated. The dependence of the reaction rate on Mg2+ concentration suggests a kinetic scheme in which a Mg2+ ion must bind before ligation can proceed. Mn2+, Ca2+, Sr2+, and Ba2+ can also catalyze the reaction. Although Pb2+ and Zn2+ do not catalyze the reaction in the absence of other divalent ions, they significantly modulate the reaction rate when added in the presence of Mg2+, with Pb2+ stimulating the reaction (up to 65-fold) and Zn2+ inhibiting the reaction. The logarithm of the ligation rate increases linearly, with slope of 0.95, as a function of pH, indicating that the reaction involves a single critical deprotonation step. The ligation rates observed with the different divalent metal ion catalysts (Mn2+ > Mg2+ > Ca2+ > Sr2+ = Ba2+) vary inversely with the pKa values of their bound water molecules. The pH profile and these relative ligation rates suggest a mechanism in which a metal-bound hydroxide ion located near the ligation junction promotes catalysis, most likely by deprotonation of the hydroxl nucleophile. The effects of changing either the leaving group or the attacking hydroxyl, together with the large delta S(++) value for oligonucleotide ligation (about -20 eu), are consistent with an associative transition state.

  13. Hepatic Venous Waveform, Splenoportal and Damping Index in Liver Cirrhosis: Correlation with Child Pugh’s Score and Oesophageal Varices

    PubMed Central

    Antil, Neha; Mittal, Mahesh Kumar; Malik, Amita; Gupta, Bhupender; Thukral, Brij Bhushan

    2016-01-01

    Introduction Clinical assessment of chronic liver disease is done by Modified Child Pugh’s and Model for end-stage liver disease scoring system. Measurement of hepatic venous pressure gradient (HVPG) and Upper GI Endoscopy are considered the gold standards for measurement of portal hypertension in cirrhotics. There is a need for non-invasive evaluation of portal hypertension. Ultrasonography with colour and spectral Doppler evaluation may be an effective, rapid and inexpensive alternative. Aim To evaluate hepatic venous waveform, damping index, splenoportal index in patients of cirrhosis on Colour Doppler ultrasound, also predict severity of portal hypertension and presence of oesophageal varices. Materials and Methods Thirty patients of chronic liver disease were included in the study. Ultrasound and colour Doppler was done to look hepatic venous waveform pattern, Damping Index (DI), and Splenoportal Index (SPI). Contrast-enhanced Computed Tomography scan (CT) was done if renal function tests were normal, else endoscopy when the renal function tests were deranged to look for oesophageal varices. Results Twenty two (73.3%) patients had monophasic waveform. Biphasic and triphasic waveforms were seen in 4 (13.3%) cases. Twenty two patients (73.3%) had monophasic waveforms and majority of them were in class C. This distribution of hepatic vein waveform was statistically significantly with the Child Pugh’s class (p<0.05). Twenty patients (66.7%) had value of Damping index more than >0.6 where majority of patients (18) belonged to class C and 2 in class B. There was a positive correlation between Child Pugh’s total score and Damping index (r=0.614; p<0.05). There was weak positive correlation between splenoportal index and Child Pugh’s score (r=0.269; p=0.15). Conclusion Change in triphasic to monophasic waveform and DI >0.6 suggests severe liver dysfunction and is associated with severe portal hypertension. Hepatic venous waveform pressure changes, DI and SPI

  14. Long-term results of complete and partial ligation of congenital portosystemic shunts in dogs.

    PubMed

    Hottinger, H A; Walshaw, R; Hauptman, J G

    1995-01-01

    The medical records of 65 dogs that underwent complete or partial ligation of a single congenital portosystemic shunt (CPSS) were reviewed to determine the long-term clinical clinical results. Information retrieved from the records included age at surgery, preligation (baseline) portal pressure, postligation portal pressure, change in portal pressure from baseline, complete or partial occlusion of the shunting vessel and fasting, and 2-hour postprandial bile acids from the preoperative, early postoperative (PO), and greater than 1 year PO time periods. A clinical rating score derived from a follow-up examination greater than 1 year PO was assigned to each dog. Of the 56 dogs that survived the perioperative period, 29 (52%) had complete and 27 (48%) had partial ligations. Age at surgery, pre- and postligation portal pressure, change in portal pressure from baseline and serum bile acid concentrations were not related to long-term clinical outcome. Clinical rating scores were significantly greater for dogs with partial CPSS ligations compared with dogs with complete ligations, indicating a less favorable clinical outcome for partial ligations. Fasting and 2-hour postprandial bile acid values at both PO time intervals were significantly greater in partial versus complete ligation groups. Follow-up information for more than 1 year was available on 18 of 29 dogs (62%) with complete ligations. All were clinically normal. Of 27 dogs with partial ligations, 11 dogs (41%) developed recurrence of clinical signs resulting in presentation to the university or referring veterinarian for additional surgery, medical management, or euthanasia. Only three dogs with partial CPSS ligation (11%) were clinically normal.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7571385

  15. Isolation and characterization of portal branch ligation-stimulated Hmga2-positive bipotent hepatic progenitor cells

    SciTech Connect

    Sakai, Hiroshi; Tagawa, Yoh-ichi; Tamai, Miho; Motoyama, Hiroaki; Ogawa, Shinichiro; Soeda, Junpei; Nakata, Takenari; Miyagawa, Shinichi

    2010-12-17

    Research highlights: {yields} Hepatic progenitor cells were isolated from the portal branch-ligated liver of mice. {yields} Portal branch ligation-stimulated hepatic progenitor cells (PBLHCs) express Hmga2. {yields} PBLHCs have bidirectional differentiation capability in vitro. -- Abstract: Hepatic stem/progenitor cells are one of several cell sources that show promise for restoration of liver mass and function. Although hepatic progenitor cells (HPCs), including oval cells, are induced by administration of certain hepatotoxins in experimental animals, such a strategy would be inappropriate in a clinical setting. Here, we investigated the possibility of isolating HPCs in a portal branch-ligated liver model without administration of any chemical agents. A non-parenchymal cell fraction was prepared from the portal branch-ligated or non-ligated lobe, and seeded onto plates coated with laminin. Most of the cells died, but a small number were able to proliferate. These proliferating cells were cloned as portal branch ligation-stimulated hepatic cells (PBLHCs) by the limiting dilution method. The PBLHCs expressed cytokeratin19, albumin, and Hmga2. The PBLHCs exhibited metabolic functions such as detoxification of ammonium ions and synthesis of urea on Matrigel-coated plates in the presence of oncostatin M. In Matrigel mixed with type I collagen, the PBLHCs became rearranged into cystic and tubular structures. Immunohistochemical staining demonstrated the presence of Hmga2-positive cells around the interlobular bile ducts in the portal branch-ligated liver lobes. In conclusion, successful isolation of bipotent hepatic progenitor cell clones, PBLHCs, from the portal branch-ligated liver lobes of mice provides the possibility of future clinical application of portal vein ligation to induce hepatic progenitor cells.

  16. Description of a novel technique for suture ligation of the renal vessels during robotic nephrectomy.

    PubMed

    Patel, Manish N; Laungani, Rajesh; Shrivastava, Alok; Bhandari, Akshay; Spencer Krane, L; Menon, Mani; Rogers, Craig G

    2009-03-01

    Minimally invasive techniques are frequently used for surgical treatment of suspected malignant renal masses. We previously reported on our experience with robotic nephrectomy and the feasibility of performing suture ligation of the renal vessels using robotic needle drivers. We describe a novel technique for suture ligation of the renal vessels during robotic nephrectomy utilizing the robotic hook and a suture with loops at each end. Our technique for suture ligation of the renal vessels recapitulates the open technique without the need for exchanging the robotic working instruments for robotic needle drivers and without the need for endovascular staplers. PMID:27628449

  17. Effect of Ligation Method on Maxillary Arch Force/Moment Systems for a Simulated Lingual Incisor Malalignment

    PubMed Central

    Seru, Surbhi; Romanyk, Dan L; Toogood, Roger W; Carey, Jason P; Major, Paul W

    2014-01-01

    Introduction: The objectives of this study were to determine whether there is a difference in the magnitude of forces and moments produced by elastic ligation when compared to passive ligation, and whether these forces and moments propagate differently along the arch for the two ligation types. A lingual incisor malalignment was used in this study. Methods: The Orthodontic Simulator (OSIM) was used to quantify the three-dimensional forces and moments applied on the teeth given a lingually displaced incisor. A repeated measures MANOVA was performed to statistically analyze the data. Results: The interaction factor illustrated convincing evidence that there is a difference in maximum force and moment values for all outcome variables between ligation types considering all tooth positions along the arch. The mean differences for FX and FY between ligation types were found to be clinically significant, with values for elastic ligation consistently higher than passive ligation. Conclusion: It was found that the maximum forces and moments produced by elastic ligation are greater than those produced by passive ligation and that the magnitude of this difference for the mesiodistal and buccolingual forces is clinically relevant. Additionally, it was determined that elastic ligation causes forces and moments to propagate further along the arch than passive ligation for all outcome variables. PMID:25400715

  18. A Novel Model of Severe Gallstone Pancreatitis: Murine Pancreatic Duct Ligation Results in Systemic Inflammation and Substantial Mortality

    PubMed Central

    Samuel, Isaac; Yuan, Zuobiao; Meyerholz, David K.; Twait, Erik; Williard, Deborah E.; Kempuraj, Duraisamy

    2010-01-01

    Background Suitable experimental models of gallstone pancreatitis with systemic inflammation and mortality are limited. We developed a novel murine model of duct-ligation-induced acute pancreatitis associated with multiorgan dysfunction and severe mortality. Methods Laparotomy was done on C57/BL6 mice followed by pancreatic duct (PD) ligation, bile duct (BD) ligation without PD ligation, or sham operation. Results Only mice with PD ligation developed acute pancreatitis and had 100% mortality. Pulmonary compliance was significantly reduced after PD ligation but not BD ligation. Bronchoalveolar lavage fluid neutrophil count and interleukin-1β concentration, and the plasma creatinine level, were significantly elevated with PD ligation but not BD ligation. Pancreatic nuclear factor κB (p65) and activator protein 1 (c-Jun) were activated within 1 h of PD ligation. Conclusion PD-ligation-induced acute pancreatitis in mice is associated with systemic inflammation, acute lung injury, multiorgan dysfunction and death. The development of this novel model is an exciting and notable advance in the field. PMID:20975317

  19. Transjugular intrahepatic portosystemic shunt combined with esophagogastric variceal embolization in the treatment of a large gastrorenal shunt

    PubMed Central

    Jiang, Qin; Wang, Ming-Quan; Zhang, Guo-Bing; Wu, Qiong; Xu, Jian-Ming; Kong, De-Run

    2016-01-01

    AIM: To evaluate the efficacy and safety of transjugular intrahepatic portosystemic shunt (TIPS) combined with stomach and esophageal variceal embolization (SEVE) in cirrhotic patients with a large gastrorenal vessel shunt (GRVS). METHODS: Eighty-one cirrhotic patients with gastric variceal bleeding (GVB) associated with a GRVS were enrolled in the study and accepted TIPS combined with SEVE (TIPS + SEVE), by which portosystemic pressure gradient (PPG), biochemical, TIPS-related complications, shunt dysfunction, rebleeding, and death were evaluated. RESULTS: The PPGs before TIPS were greater than 12 mmHg in 81 patients. TIPS + SEVE treatment caused a significant decrease in PPG (from 37.97 ± 6.36 mmHg to 28.15 ± 6.52 mmHg, t = 19.22, P < 0.001). The percentage of reduction in PPG was greater than 20% from baseline. There were no significant differences in albumin, alanine aminotransferase, aspartate aminotransferase, bilirubin, prothrombin time, or Child-Pugh score before and after operation. In all patients, rebleeding rates were 3%, 6%, 12%, 18%, and 18% at 1, 3, 6, 12, and 18 mo, respectively. Five patients (6.2%) were diagnosed as having hepatic encephalopathy. The rates of shunt dysfunction were 0%, 4%, 9%, 26%, and 26%, at 1, 3, 6, 12, and 18 mo, respectively. The cumulative survival rates in 1, 3, 6, 12, and 18 mo were 100%, 100%, 95%, 90%, and 90%, respectively. CONCLUSION: Our preliminary results indicated that the efficacy and safety of TIPS + SEVE were satisfactory in cirrhotic patients with GVB associated with a GRVS (GVB + GRVS). PMID:27458505

  20. Melatonin Alleviates Liver Apoptosis in Bile Duct Ligation Young Rats

    PubMed Central

    Sheen, Jiunn-Ming; Chen, Yu-Chieh; Hsu, Mei-Hsin; Tain, You-Lin; Huang, Ying-Hsien; Tiao, Mao-Meng; Li, Shih-Wen; Huang, Li-Tung

    2016-01-01

    Bile duct ligation (BDL)-treated rats display cholestasis and liver damages. The potential protective activity of melatonin in young BDL rats in terms of apoptosis, mitochondrial function, and endoplasmic reticulum (ER) homeostasis has not yet been evaluated. Three groups of young male Sprague-Dawley rats were used: one group received laparotomy (Sham), a second group received BDL for two weeks (BDL), and a third group received BDL and intraperitoneal melatonin (100 mg/day) for two weeks (BDL + M). BDL group rats showed liver apoptosis, increased pro-inflamamtory mediators, caspases alterations, anti-apoptotic factors changes, and dysfunction of ER homeostasis. Melatonin effectively reversed apoptosis, mainly through intrinsic pathway and reversed ER stress. In addition, in vitro study showed melatonin exerted its effect mainly through the melatonin 2 receptor (MT2) in HepG2 cells. In conclusion, BDL in young rats caused liver apoptosis. Melatonin rescued the apoptotic changes via the intrinsic pathway, and possibly through the MT2 receptor. Melatonin also reversed ER stress induced by BDL. PMID:27556445

  1. Endoscopic band ligation for bleeding lesions in the small bowel

    PubMed Central

    Ikeya, Takashi; Ishii, Naoki; Shimamura, Yuto; Nakano, Kaoru; Ego, Mai; Nakamura, Kenji; Takagi, Koichi; Fukuda, Katsuyuki; Fujita, Yoshiyuki

    2014-01-01

    AIM: To investigate the safety and efficacy of endoscopic band ligation (EBL) for bleeding lesions in the small bowel. METHODS: This is a retrospective study evaluating EBL in six consecutive patients (three males, three females, 46-86 years of age) treated between May 2009 and February 2014: duodenal vascular ectasia; 1, jejunal bleeding diverticulum; 1, ileal Dieulafoy’s lesion; 1 and ileal bleeding diverticula; 3. The success of the initial hemostasis was evaluated, and patients were observed for early rebleeding (within 30 d after EBL), and complications such as perforation and abscess formation. Follow-up endoscopies were performed in four patients. RESULTS: Initial hemostasis was successfully achieved with EBL in all six patients. Eversion was not sufficient in four diverticular lesions. Early rebleeding occurred three days after EBL in one ileal diverticulum, and a repeat endoscopy revealed dislodgement of the O-band and ulcer formation at the banded site. This rebleeding was managed conservatively. Late rebleeding occurred in this case (13 and 21 mo after initial EBL), and re-EBL was performed. Follow-up endoscopies revealed scar formation and the disappearance of vascular lesions at the banded site in the case with a duodenal bleeding lesion, and unresolved ileal diverticula in three cases. Surgery or transarterial embolization was not required without any complications during the median follow-up period of 45 (range, 2-83) mo. CONCLUSION: EBL is a safe and effective endoscopic treatment for hemostasis of bleeding lesions in the small bowel. PMID:25324920

  2. Characterizing seamless ligation cloning extract for synthetic biological applications.

    PubMed

    Messerschmidt, Katrin; Hochrein, Lena; Dehm, Daniel; Schulz, Karina; Mueller-Roeber, Bernd

    2016-09-15

    Synthetic biology aims at designing and engineering organisms. The engineering process typically requires the establishment of suitable DNA constructs generated through fusion of multiple protein coding and regulatory sequences. Conventional cloning techniques, including those involving restriction enzymes and ligases, are often of limited scope, in particular when many DNA fragments must be joined or scar-free fusions are mandatory. Overlap-based-cloning methods have the potential to overcome such limitations. One such method uses seamless ligation cloning extract (SLiCE) prepared from Escherichia coli cells for straightforward and efficient in vitro fusion of DNA fragments. Here, we systematically characterized extracts prepared from the unmodified E. coli strain DH10B for SLiCE-mediated cloning and determined DNA sequence-associated parameters that affect cloning efficiency. Our data revealed the virtual absence of length restrictions for vector backbone (up to 13.5 kbp) and insert (90 bp to 1.6 kbp). Furthermore, differences in GC content in homology regions are easily tolerated and the deletion of unwanted vector sequences concomitant with targeted fragment insertion is straightforward. Thus, SLiCE represents a highly versatile DNA fusion method suitable for cloning projects in virtually all molecular and synthetic biology projects. PMID:27311554

  3. Melatonin Alleviates Liver Apoptosis in Bile Duct Ligation Young Rats.

    PubMed

    Sheen, Jiunn-Ming; Chen, Yu-Chieh; Hsu, Mei-Hsin; Tain, You-Lin; Huang, Ying-Hsien; Tiao, Mao-Meng; Li, Shih-Wen; Huang, Li-Tung

    2016-01-01

    Bile duct ligation (BDL)-treated rats display cholestasis and liver damages. The potential protective activity of melatonin in young BDL rats in terms of apoptosis, mitochondrial function, and endoplasmic reticulum (ER) homeostasis has not yet been evaluated. Three groups of young male Sprague-Dawley rats were used: one group received laparotomy (Sham), a second group received BDL for two weeks (BDL), and a third group received BDL and intraperitoneal melatonin (100 mg/day) for two weeks (BDL + M). BDL group rats showed liver apoptosis, increased pro-inflamamtory mediators, caspases alterations, anti-apoptotic factors changes, and dysfunction of ER homeostasis. Melatonin effectively reversed apoptosis, mainly through intrinsic pathway and reversed ER stress. In addition, in vitro study showed melatonin exerted its effect mainly through the melatonin 2 receptor (MT2) in HepG2 cells. In conclusion, BDL in young rats caused liver apoptosis. Melatonin rescued the apoptotic changes via the intrinsic pathway, and possibly through the MT2 receptor. Melatonin also reversed ER stress induced by BDL. PMID:27556445

  4. Expressed protein ligation-mediated template protein extension.

    PubMed

    Kamei, Ayako; Hauser, Paul S; Beckstead, Jennifer A; Weers, Paul M M; Ryan, Robert O

    2012-06-01

    Expressed protein ligation (EPL) was performed to investigate sequence requirements for a variant human apolipoprotein A-I (apoA-I) to adopt a folded structure. A C-terminal truncated apoA-I, corresponding to residues 1-172, was expressed and isolated from Escherichia coli. Compared to full length apoA-I (243 amino acids), apoA-I(1-172) displayed less α-helix secondary structure and lower stability in solution. To determine if extension of this polypeptide would confer secondary structure content and/or stability, 20 residues were added to the C-terminus of apoA-I(1-172) by EPL, creating apoA-I(Milano)(1-192). The EPL product displayed biophysical properties similar to full-length apoA-I(Milano). The results provide a general protein engineering strategy to modify the length of a recombinant template polypeptide using synthetic peptides as well as a convenient, cost effective way to investigate the structure/function relations in apolipoprotein fragments or domains of different size.

  5. Phototriggered DNA phosphoramidate ligation in a tandem 5'-amine deprotection/3'-imidazole activated phosphate coupling reaction.

    PubMed

    Cape, Jonathan L; Edson, Joseph B; Spencer, Liam P; DeClue, Michael S; Ziock, Hans-Joachim; Maurer, Sarah; Rasmussen, Steen; Monnard, Pierre-Alain; Boncella, James M

    2012-10-17

    We report the preparation and use of an N-methyl picolinium carbamate protecting group for applications in a phototriggered nonenzymatic DNA phosphoramidate ligation reaction. Selective 5'-amino protection of a modified 13-mer oligonucleotide is achieved in aqueous solution by reaction with an N-methyl-4-picolinium carbonyl imidazole triflate protecting group precursor. Deprotection is carried out by photoinduced electron transfer from Ru(bpy)(3)(2+) using visible light photolysis and ascorbic acid as a sacrificial electron donor. Phototriggered 5'- amino oligonucleotide deprotection is used to initiate a nonenzymatic ligation of the 13-mer to an imidazole activated 3'-phospho-hairpin template to generate a ligated product with a phosphoramidate linkage. We demonstrate that this methodology offers a simple way to exert control over reaction initiation and rates in nonenzymatic DNA ligation for potential applications in the study of model protocellular systems and prebiotic nucleic acid synthesis.

  6. Chemoselective modifications for the traceless ligation of thioamide-containing peptides and proteins.

    PubMed

    Wang, Yanxin J; Szantai-Kis, D Miklos; Petersson, E James

    2016-07-14

    Thioamides are single-atom substitutions of canonical amide bonds, and have been proven to be versatile and minimally perturbing probes in protein folding studies. Previously, our group showed that thioamides can be incorporated into proteins by native chemical ligation (NCL) with Cys as a ligation handle. In this study, we report the expansion of this strategy into non-Cys ligation sites, utilizing radical initiated desulfurization to "erase" the side chain thiol after ligation. The reaction exhibited high chemoselectivity against thioamides, which can be further enhanced with thioacetamide as a sacrificial scavenger. As a proof-of-concept example, we demonstrated the incorporation of a thioamide probe into a 56 amino acid protein, the B1 domain of Protein G (GB1). Finally, we showed that the method can be extended to β-thiol amino acid analogs and selenocysteine. PMID:27264841

  7. Chemical ligation methods for the tagging of DNA-encoded chemical libraries.

    PubMed

    Keefe, Anthony D; Clark, Matthew A; Hupp, Christopher D; Litovchick, Alexander; Zhang, Ying

    2015-06-01

    The generation of DNA-encoded chemical libraries requires the unimolecular association of multiple encoding oligonucleotides with encoded chemical entities during combinatorial synthesis processes. This has traditionally been achieved using enzymatic ligation. We discuss a range of chemical ligation methods that provide alternatives to enzymatic ligation. These chemical ligation methods include the generation of modified internucleotide linkages that support polymerase translocation and other modified linkages that while not supporting the translocation of polymerases can also be used to generate individual cDNA molecules containing encoded chemical information specifying individual library members. We also describe which of these approaches have been successfully utilized for the preparation of DNA-encoded chemical libraries and those that were subsequently used for the discovery of inhibitors.

  8. Heated oligonucleotide ligation assay (HOLA): an affordable single nucleotide polymorphism assay.

    PubMed

    Black, W C; Gorrochotegui-Escalante, N; Duteau, N M

    2006-03-01

    Most single nucleotide polymorphism (SNP) detection requires expensive equipment and reagents. The oligonucleotide ligation assay (OLA) is an inexpensive SNP assay that detects ligation between a biotinylated "allele-specific detector" and a 3' fluorescein-labeled "reporter" oligonucleotide. No ligation occurs unless the 3' detector nucleotide is complementary to the SNP nucleotide. The original OLA used chemical denaturation and neutralization. Heated OLA (HOLA) instead uses a thermal stable ligase and cycles of denaturing and hybridization for ligation and SNP detection. The cost per genotype is approximately US$1.25 with two-allele SNPs or approximately US$1.75 with three-allele SNPs. We illustrate the development of HOLA for SNP detection in the Early Trypsin and Abundant Trypsin loci in the mosquito Aedes aegypti (L.) and at the a-glycerophosphate dehydrogenase locus in the mosquito Anopheles gambiae s.s.

  9. Robotic-assisted left atrial ligation for stroke reduction in chronic atrial fibrillation: a case report.

    PubMed

    Kiaii, Bob; McClure, R Scott; Skanes, Alan C; Ross, Ian G; Spouge, Alison R; Swinamer, Stuart; Rayman, Reiza; Bainbridge, Daniel T; Iglesias, Ivan; Novick, Richard J

    2006-01-01

    Patients with atrial fibrillation are at significant risk for sustaining a thromboembolic stroke. More than 90% of thromboemboli form in the left atrial appendage. Ligation of the left atrial appendage to reduce the risk of stroke is often performed in connection with other cardiac surgical procedures. As a stand-alone procedure, however, left atrial ligation has generally been deemed too invasive and has gained little support as an alternative therapeutic option. We report a case of port-access robotic-assisted left atrial ligation as a stand-alone procedure in a patient with chronic atrial fibrillation in whom anticoagulation was a contraindication. To our knowledge, this is the first reported case of stand-alone robotic-assisted left atrial ligation in the literature. PMID:16387671

  10. Comparison of frictional resistance of esthetic and semi-esthetic self-ligating brackets

    PubMed Central

    Kannan, M. S.; Murali, R. V.; Kishorekumar, S.; Gnanashanmugam, K.; Jayanth, V.

    2015-01-01

    Aim: The frictional resistance encountered during sliding mechanics has been well established in the orthodontic literature, and it consists of complex interactions between the bracket, archwire, and method of ligation the claim of reduced friction with self-ligating brackets is often cited as a primary advantage over conventional brackets. This study was done to compare and evaluate the frictional forces generated between fully esthetic brackets and semi-aesthetic self-ligating brackets, which are of passive form and SEM (scanning electron microscope) study of the Brackets after Frictional evaluation. Materials and Methods: Two types of self-ligating esthetic brackets, Damon clear (Ormco) made of fully ceramic and Opal (Ultradent Products, USA) and, Two types of self-ligating semi-esthetic brackets, Clarity SL (3M Unitek) and Damon 3 (Ormco) both of which are made of ceramic with metal slot. Arch wires with different dimensions and quality 17 × 25, 19 × 25 Titanium Molybdenum Alloy (TMA) and 17 × 25, 19 × 25 stainless steel that came from plain strands of wire were used for frictional comparison test. The brackets used in this study had 0.022 × 0.028 inch slot. Results: The statistical tests showed significantly smaller amount of kinetic frictional forces is generated by Damon 3 (semi-esthetic self-ligating brackets). For each wire used, Damon 3 displayed significantly lower frictional forces (P ≤ 0.05) than any of the self-ligating system, followed by Opal (fully esthetic self-ligating brackets) which generated smaller amount of frictional forces but relatively on the higher side when compared with Damon 3. Damon clear (fully esthetic self-ligating brackets) generated the maximum amount of kinetic forces with all types of wire dimensions and properties when compared to the other three types of self-ligating system. Clarity SL (semi-esthetic self-ligating brackets) generated smaller amount of frictional forces when compared with Damon clear and relatively

  11. Ligation of RNA Oligomers by the Schistosoma mansoni Hammerhead Ribozyme in Frozen Solution.

    PubMed

    Lie, Lively; Biliya, Shweta; Vannberg, Fredrik; Wartell, Roger M

    2016-03-01

    The interstitial liquid phase within frozen aqueous solutions is an environment that minimizes RNA degradation and facilitates reactions that may have relevance to the RNA World hypothesis. Previous work has shown that frozen solutions support condensation of activated nucleotides into RNA oligomers, RNA ligation by the hairpin ribozyme, and RNA synthesis by a RNA polymerase ribozyme. In the current study, we examined the activity of a hammerhead ribozyme (HHR) in frozen solution. The Schistosoma mansoni hammerhead ribozyme, which predominantly cleaves RNA, can ligate its cleaved products (P1 and P2) with yields up to ~23 % in single turnover experiments at 25 °C in the presence of Mg(2+). Our studies show that this HHR ligates RNA oligomers in frozen solution in the absence of divalent cations. Citrate and other anions that exhibit strong ion-water affinity enhanced ligation. Yields up to 43 % were observed in one freeze-thaw cycle and a maximum of 60 % was obtained after several freeze-thaw cycles using wild-type P1 and P2. Truncated and mutated P1 substrates were ligated to P2 with yields of 14-24 % in one freeze-thaw cycle. A pool of P2 substrates with mixtures of all four bases at five positions were ligated with P1 in frozen solution. High-throughput sequencing indicated that 70 of the 1024 possible P2 sequences were represented in ligated products at 1000 or more read counts per million reads. The results indicate that the HHR can ligate a range of short RNA oligomers into an ensemble of diverse sequences in ice.

  12. The Early Postoperative Complications of Two Different Tube Ligation Methods in Baerveldt Implant Surgery

    PubMed Central

    Hamanaka, Teruhiko; Sakurai, Testurou

    2014-01-01

    ABSTRACT Objective: To investigate the early postoperative complications in two different tube ligation methods during the first 3 months in Baerveldt implant surgery. Participants: This study involved 157 eyes from 144 patients who underwent Baerveldt Implant Surgery at the Japanese Red Cross Medical Center, Tokyo, Japan. Methods: Pre- and postoperative intraocular pressure (IOP), combined surgery, postoperative time-point of tube ligation release, and postoperative complications in two different tube ligation methods [absorbable ligation method using 8-0 polyglactin suture (group A) and nonabsorbable ligation method using 7-0 nylon suture (group B)] were retrospectively reviewed. Results: After excluding eyes that had undergone combined trabeculectomy (26 eyes) and vitrectomy (2 eyes), eyes with previous tube surgery (22 eyes), and eyes that had undergone the stent method (1 eye), 30 of 28 patients in group A and 71 eyes of 71 patients in group B were found to fit the criteria of this study. The rate of successful surgical outcome was 80% in group A and 74.6% in group B (p = 0.705). During the 3 months postoperative, high IOP tended to occur more often in group B (67.6%) than in group A (46.7%) (p = 0.073), and ciliochoroidal detachment tended to occur more often in group A (10.0%) than group B (2.8%) (p = 0.154). Conclusion: The results of this study show that both ligation methods are effective, however, the selection of tube ligation method should be done in accordance with the different method-specific risks to which may occur. How to cite this article: Kawamorita S, Hamanaka T, Sakurai T. The Early Postoperative Complications of Two Different Tube Ligation Methods in Baerveldt Implant Surgery. J Curr Glaucoma Pract 2014;8(3):96-100. PMID:26997819

  13. Force loss in archwire-guided tooth movement of conventional and self-ligating brackets.

    PubMed

    Montasser, Mona A; El-Bialy, Tarek; Keilig, Ludger; Reimann, Susanne; Jäger, Andreas; Bourauel, Christoph

    2014-02-01

    This study aimed to investigate the differences in the force loss during simulated archwire-guided canine retraction between various conventional and self-ligating brackets. Three types of orthodontic brackets have been investigated experimentally using a biomechanical set-up: 1. conventional ligating brackets (Victory Series and Mini-Taurus), 2. self-ligating brackets (SmartClip: passive self-ligating bracket, and Time3 and SPEED: active self-ligating brackets), and 3. a conventional low-friction bracket (Synergy). All brackets had a nominal 0.022″ slot size. The brackets were combined with three rectangular 0.019×0.025″ archwires: 1. Remanium (stainless steel), 2. Nitinol SE (nickel-titanium alloy, NiTi), and 3. Beta III Titanium (titanium-molybdenum alloy). Stainless steel ligatures were used with the conventional brackets. Archwire-guided tooth movement was simulated over a retraction path of up to 4mm using a superelastic NiTi coil spring (force: 1 N). Force loss was lowest for the Victory Series and SmartClip brackets in combination with the steel guiding archwire (35 and 37.6 per cent, respectively) and highest for the SPEED and Mini-Taurus brackets in combination with the titanium wire (73.7 and 64.4 per cent, respectively). Force loss gradually increased by 10 per cent for each bracket type in combination with the different wires in the following sequence: stainless steel, Nitinol, and beta-titanium. Self-ligating brackets did not show improved performance compared with conventional brackets. There was no consistent pattern of force loss when comparing conventional and self-ligating brackets or passive and active self-ligating brackets. PMID:23382468

  14. Blood flow changes after unilateral carotid artery ligation monitored by optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Ma, Yushu; Liang, Chengbo; Suo, Yanyan; Zhao, Yuqian; Wang, Yi; Xu, Tao; Wang, Ruikang; Ma, Zhenhe

    2016-03-01

    Unilateral carotid artery ligation which could induce adaptive improvement is a classic model that has been widely used to study pathology of ischemic disease. In those studies, blood flow is an important parameter to characterize the ischemia. Optical coherence tomography (OCT) is a powerful imaging modality which can provide depth resolved images in biological tissue with high spatial and temporal resolution. SPF rats was anesthetized with isoflurane and divided into two groups. In first group, bilateral carotid artery was surgically exposed, and then left carotid artery was ligated. Blood flow changes of the contralateral carotid artery was monitored using high speed spectral domain optical coherence tomography, including the absolute flow velocity and the flow volume. In the other group, skull window was opened at the ipsilateral cerebral cortex of ligation and blood supply of small artery was measured before and after the ligation. The measured results demonstrate the blood supply compensation process after unilateral carotid artery ligation. With the superiority of high resolution, OCT is an effective technology in monitoring results of carotid artery after ligation.

  15. KAHA ligations that form aspartyl aldehyde residues as synthetic handles for protein modification and purification.

    PubMed

    Murar, Claudia E; Thuaud, Frédéric; Bode, Jeffrey W

    2014-12-31

    Aldehydes are widely recognized as valuable synthetic handles for the chemoselective manipulation of peptides and proteins. In this report, we show that peptides and small proteins containing the aspartic acid semialdehyde (Asa) side chain can be easily prepared by a chemoselective amide-forming ligation that results in the formation of the Asa residue at the ligation site. This strategy employs the α-ketoacid-hydroxylamine (KAHA) ligation in combination with a new isoxazolidine monomer that forms a side-chain aldehyde upon ligation. This monomer is easily prepared on a preparative scale by a catalytic, enantioselective approach and is readily introduced onto the N-terminus of a peptide segment by solid phase peptide synthesis. The ligated product can be further functionalized by bioorthogonal reactions between the aldehyde residue and alkoxyamines or hydrazides. We demonstrated that glucagon aldehyde, an unprotected 29-mer peptide prepared by KAHA ligation, can be site specifically and chemoselectively modified with biotin, dyes, aliphatic oximes, and hydroxylamines. We further describe a simple and high recovery one-step purification process based on the capture of a 29-mer glucagon aldehyde and a 76-mer ubiquitin aldehyde by an alkoxyamine-functionalized polyethylene glycol resin. The peptide or protein was released from the resin by addition of a hydroxylamine to provide the corresponding oximes.

  16. A novel, one-step amplification and oligonucleotide ligation procedure for multiplex genetic typing

    SciTech Connect

    Eggerding, F.A.

    1994-09-01

    A new technique, coupled amplification and oligonucleotide ligation (CAL), has been developed for simultaneous multiplex amplification and genotyping of DNA. CAL is a biphasic method which combines in one assay DNA amplification by the polymerase chain reaction (PCR) with DNA genotyping by the oligonucleotide ligation assay (OLA). By virtue of a difference in the melting temperatures of PCR primer-target DNA and OLA probe-target DNA hybrids, the method allows preferential amplification of DNA during stage I and oligonucleotide ligation during stage II of the reaction. In stage I target DNA is amplified using high-melting primers in a two-step PCR cycle that employs a 72{degrees}C anneal-elongation step. In stage II genotyping of PCR products by competitive oligonucleotide ligation with oligonucleotide probes located between PCR primers is accomplished by several cycles of denaturation at 94{degrees}C followed by anneal-ligation at 55{degrees}C. Ligation products are fluorochrome-labeled at their 3{prime}-ends and analyzed electrophoretically on a fluorescent DNA sequencer. The CAL procedure has been used for multiplex detection of 30 cystic fibrosis mutations and for analysis of ras gene point mutations. Because mutation detection occurs concurrently with target amplification, the technique is rapid, highly sensitive and specific, easily automatable, and requires minimal sample processing.

  17. Prospective comparison of ligation and bipolar cautery technique in non-scalpel vasectomy

    PubMed Central

    Altok, Muammer; Şahin, Ali Feyzullah; Divrik, Rauf Taner; Yildirim, Ümit; Zorlu, Ferruh

    2015-01-01

    ABSTRACT Objectives: There is no trial comparing bipolar cautery and ligation for occlusion of vas in non-scalpel vasectomy. This study aimed to compare the effectiveness of these vasectomy occlusion techniques. Materials and Methods: Between January 2002-June 2009, patients were allocated in alternate order. We recruited 100 cases in cautery group and 100 cases in ligation group. Non-scalpel approach was performed during vasectomy and fascial interposition was performed in all cases. First semen analysis was done 3 months after vasectomy. Vasectomy success was defined as azoospermia or non-motile sperm lower than 100.000/mL. Results: Four patients from the cautery group were switched to the ligation group due to technical problem of cautery device. Thus, data of 96 patients as cautery group and 104 patients as ligation group were evaluated. After vasectomy, semen analyses were obtained from 59 of 96 (61.5%) patients in cautery group and to 66 of 104 (63.5%) patients in ligation group. There was no statistical significant difference between the two groups in terms of the success of vasectomy (p=0.863). Conclusion: Although bipolar cautery technique is safe, effective and feasible in non-scalpel vasectomy, it has no superiority to ligation. There was no statistically significant difference in terms of the success and complications between the two groups. PMID:26742977

  18. Formation of oligonucleotide-PNA-chimeras by template-directed ligation

    NASA Technical Reports Server (NTRS)

    Koppitz, M.; Nielsen, P. E.; Orgel, L. E.; Bada, J. L. (Principal Investigator)

    1998-01-01

    DNA sequences have previously been reported to act as templates for the synthesis of PNA, and vice versa. A continuous evolutionary transition from an informational replicating system based on one polymer to a system based on the other would be facilitated if it were possible to form chimeras, that is molecules that contain monomers of both types. Here we show that ligation to form chimeras proceeds efficiently both on PNA and on DNA templates. The efficiency of ligation is primarily determined by the number of backbone bonds at the ligation site and the relative orientation of template and substrate strands. The most efficient reactions result in the formation of chimeras with ligation junctions resembling the structures of the backbones of PNA and DNA and with antiparallel alignment of both components of the chimera with the template, that is, ligations involving formation of 3'-phosphoramidate and 5'-ester bonds. However, double helices involving PNA are stable both with antiparallel and parallel orientation of the two strands. Ligation on PNA but not on DNA templates is, therefore, sometimes possible on templates with reversed orientation. The relevance of these findings to discussions of possible transitions between genetic systems is discussed.

  19. Treatment of glioblastoma multiforme cells with temozolomide-BioShuttle ligated by the inverse Diels-Alder ligation chemistry

    PubMed Central

    Braun, Klaus; Wiessler, Manfred; Ehemann, Volker; Pipkorn, Ruediger; Spring, Herbert; Debus, Juergen; Didinger, Bernd; Koch, Mario; Muller, Gabriele; Waldeck, Waldemar

    2008-01-01

    Recurrent glioblastoma multiforme (GBM), insensitive against most therapeutic interventions, has low response and survival rates. Temozolomide (TMZ) was approved for second-line therapy of recurrent anaplastic astrocytoma. However, TMZ therapy in GBM patients reveals properties such as reduced tolerability and inauspicious hemogram. The solution addressed here concerning GBM therapy consolidates and uses the potential of organic and peptide chemistry with molecular medicine. We enhanced the pharmacologic potency with simultaneous reduction of unwanted adverse reactions of the highly efficient chemotherapeutic TMZ. The TMZ connection to transporter molecules (TMZ-BioShuttle) was investigated, resulting in a much higher pharmacological effect in glioma cell lines and also with reduced dose rate. From this result we can conclude that a suitable chemistry could realize the ligation of pharmacologically active, but sensitive and highly unstable pharmaceutical ingredients without functional deprivation. The TMZ-BioShuttle dramatically enhanced the potential of TMZ for the treatment of brain tumors and is an attractive drug for combination chemotherapy. PMID:19920915

  20. Could there be light at the end of the tunnel? Mesocaval shunting for refractory esophageal varices in patients with contraindications to transjugular intrahepatic portosystemic shunt

    PubMed Central

    Davis, Jessica; Chun, Albert K; Borum, Marie L

    2016-01-01

    Cirrhotic patients with recurrent variceal bleeds who have failed prior medical and endoscopic therapies and are not transjugular intrahepatic portosystemic shunt candidates face a grim prognosis with limited options. We propose that mesocaval shunting be offered to this group of patients as it has the potential to decrease portal pressures and thus decrease the risk of recurrent variceal bleeding. Mesocaval shunts are stent grafts placed by interventional radiologists between the mesenteric system, most often the superior mesenteric vein, and the inferior vena cava. This allows flow to bypass the congested hepatic system, reducing portal pressures. This technique avoids the general anesthesia and morbidity associated with surgical shunt placement and has been successful in several case reports. In this paper we review the technique, candidate selection, potential pitfalls and benefits of mesocaval shunt placement. PMID:27429715

  1. Could there be light at the end of the tunnel? Mesocaval shunting for refractory esophageal varices in patients with contraindications to transjugular intrahepatic portosystemic shunt.

    PubMed

    Davis, Jessica; Chun, Albert K; Borum, Marie L

    2016-07-01

    Cirrhotic patients with recurrent variceal bleeds who have failed prior medical and endoscopic therapies and are not transjugular intrahepatic portosystemic shunt candidates face a grim prognosis with limited options. We propose that mesocaval shunting be offered to this group of patients as it has the potential to decrease portal pressures and thus decrease the risk of recurrent variceal bleeding. Mesocaval shunts are stent grafts placed by interventional radiologists between the mesenteric system, most often the superior mesenteric vein, and the inferior vena cava. This allows flow to bypass the congested hepatic system, reducing portal pressures. This technique avoids the general anesthesia and morbidity associated with surgical shunt placement and has been successful in several case reports. In this paper we review the technique, candidate selection, potential pitfalls and benefits of mesocaval shunt placement. PMID:27429715

  2. Endoscopic band ligation for colonic diverticular bleeding: possibility of standardization

    PubMed Central

    Shimamura, Yuto; Ishii, Naoki; Omata, Fumio; Imamura, Noriatsu; Okamoto, Takeshi; Ego, Mai; Nakano, Kaoru; Ikeya, Takashi; Nakamura, Kenji; Takagi, Koichi; Fukuda, Katsuyuki; Fujita, Yoshiyuki

    2016-01-01

    Background and aims: Endoscopic band ligation (EBL) has been used to achieve hemostasis in patients with colonic diverticular bleeding. The safety and effectiveness of EBL when performed by non-expert endoscopists have not been sufficiently verified. This study aimed to elucidate the feasibility of the EBL technique when performed by non-expert endoscopists and of considering EBL as a standard treatment for colonic diverticular bleeding. Patients and methods: A retrospective cohort study was conducted in a tertiary referral center in Tokyo, Japan, between June 2009 and October 2014. A total of 95 patients treated with EBL were included in the study and were divided into two groups according to whether they had been treated by expert or non-expert endoscopists. Comorbidities, medications, shock index, hemoglobin level on admission, location of the bleeding diverticula, rate of bowel preparation, procedure time, and EBL-associated adverse events were evaluated in each group. Multivariate linear regression analyses were used to investigate factors related to EBL procedure time, which is the time elapsed between marking the site of bleeding with hemoclips and completion of the band release. Results: A total of 47 (49.5 %) procedures were performed by expert endoscopists. In a bivariate analysis, the median EBL procedure times in the expert and non-expert groups were 15 minutes (range 4 – 45) and 11 minutes (range 4 – 36), respectively (P = 0.03). When a multivariate linear regression model was used, EBL for right-sided diverticula was the factor most significantly affecting EBL procedure time. No adverse events were encountered. Conclusion: EBL can be safely and effectively performed by non-expert endoscopists. A right-sided location of diverticula was the factor most significantly affecting EBL procedure time. PMID:26878056

  3. Total chemical synthesis of human psoriasin by native chemical ligation.

    PubMed

    Li, Xiangqun; de Leeuw, Erik; Lu, Wuyuan

    2005-11-01

    Human psoriasin (S100A7), a member of the S100 family of calcium-binding proteins, is richly expressed in keratinocytes of patients suffering from psoriasis. To date, the exact physiological function of psoriasin abundant in many human cell types remains unclear. A recent report by Schröder and colleagues suggests that psoriasin, purified from human stratum corneum extracts, selectively kills Escherichia coli by sequestering Zn(2+) ions essential for bacterial growth, indicative of an important role in innate immune defense against microbial infection. We chemically synthesized the N-terminally acetylated psoriasin of 100 amino acid residues using solid phase peptide synthesis in combination with native chemical ligation. More than 140 mg of highly pure and correctly folded synthetic psoriasin was obtained from a single synthesis on a 0.25 mmol scale. Analysis of synthetic psoriasin by size exclusion chromatography showed that the protein forms a homodimer in solution. Circular dichroism analysis indicated that the alpha-helicity of psoriasin increases by more than 20% in the presence of CaCl(2) or ZnCl(2), suggesting a metal ion binding induced conformational change. Circular dichroism based titration further established that the synthetic protein binds two Ca(2+) and two Zn(2+) ions per dimer, in agreement with the published structural findings. Importantly, the ability of the synthetic protein to kill E. coli and the inhibition of the killing by ZnCl(2) is comparable to that of psoriasin isolated from its natural source. The robust synthetic access to large quantities of human psoriasin should facilitate studies of its biological functions as well as its mode of action.

  4. Integrin Ligation Results in Nephrin Tyrosine Phosphorylation In Vitro

    PubMed Central

    Verma, Rakesh; Venkatareddy, Madhusudan; Kalinowski, Anne; Patel, Sanjeevkumar R.; Garg, Puneet

    2016-01-01

    Nephrin is expressed at the basolateral aspect of podocytes and is an important signaling protein at the glomerular slit diaphragm. In vitro studies have demonstrated that Nephrin phosphorylation-dependent signaling is able to assemble a protein complex that is able to polymerize actin. However, proximal signaling events that result in nephrin tyrosine phosphorylation are not well understood. Nephrin deletion in mice and human nephrin mutations result in developmental failure of the podocyte intercellular junction resutling in proteinuria. This has been presumed to be due to a failure to respond to an external polarized cue in the absence of nephrin or a failure to transduce an outside-in signal in patients with nephrin mutations. The nephrin extracellular domain binds to itself or neph1 across the foot process intercellular junction. Nephrin is tyrosine phosphorylation-silent in healthy glomeruli when presumably the nephrin extracellular domain is in an engaged state. These observations raise the possibility of an alternate proximal signaling mechanism that might be responsible for nephrin tyrosine phosphorylation. Here we present data showing that integrin engagement at the basal aspect of cultured podocytes results in nephrin tyrosine phosphorylation. This is abrogated by incubating podocytes with an antibody that prevents integrin β1 ligation and activation in response to binding to extracellular matrix. Furthermore, nephrin tyrosine phosphorylation was observed in podocytes expressing a membrane-targeted nephrin construct that lacks the extracellular domain. We propose, integrin-activation based signaling might be responsible for nephrin phosphorylation rather than engagment of the nephrin extracellular domain by a ligand. PMID:26848974

  5. Total laparoscopic hysterectomy via suture and ligation technique

    PubMed Central

    Kang, Hye Won; Lee, Ji Won; Kim, Ho Yeon; Kim, Bo Wook

    2016-01-01

    Objective The term 'total laparoscopic hysterectomy (TLH) with classical suture method' refers to a surgical procedure performed using only sutures and ligations with intracorporeal or extracorporeal ties, without using any laser or electronic cauterization devices during laparoscopic surgery as in total abdominal hysterectomy. However, the method is not as widely used as electric coagulation equipment for TLH because further advances in technology and surgical technique are required and operative time can take longer. In the current study, we evaluated the benefits of the classical suture method for TLH. Methods This study retrospectively reviewed patients who received TLH using the classical suture method from August 2005 to April 2014. The patients' baseline characteristics were analyzed, including age, parity, cause of operation, medical and surgical history. Surgical outcomes analyzed included the weight of the uterus, operative time, complications, changes in hemoglobin level, blood transfusion requirements, and postoperative hospital stay. Results Of 746 patients who underwent TLH with the classical suture method, mean operation time was 96.9 minutes. Mean average decline in hemoglobin was 1.6 g/dL and transfusion rate was 6.2%. Urinary tract injuries were reported in 8 patients. Urinary tract injuries comprised 6 cases of bladder injury and 3 cases of ureter injury. There were no cases of vaginal stump infection, hematoma, bowel injury or abdominal wound complication. All cases involving complications occurred before 2010. Conclusion The classical suture method for TLH presents tolerable levels of complications and blood loss. Advanced surgical skill is expected to decrease operation time and complications. PMID:26866034

  6. Somatostatin plus isosorbide 5-mononitrate versus somatostatin in the control of acute gastro-oesophageal variceal bleeding: a double blind, randomised, placebo controlled clinical trial

    PubMed Central

    Junquera, F; Lopez-Talavera, J; Mearin, F; Saperas, E; Videla, S; Armengol, J; Esteban, R; Malagelada, J

    2000-01-01

    BACKGROUND—Variceal bleeding is a severe complication of portal hypertension. Somatostatin reduces portal pressure by decreasing splanchnic blood flow, and nitrates by diminishing intrahepatic resistance. Experimental studies have shown that the combination of somatostatin and nitrates has an additive effect in decreasing portal pressure.
AIM—To compare the therapeutic efficacy of either intravenous infusion of somatostatin plus oral isosorbide 5-mononitrate or somatostatin alone in gastro-oesophageal variceal bleeding associated with liver cirrhosis.
METHODS—A unicentre, double blind, placebo controlled, clinical trial was conducted. Sixty patients bleeding from oesophageal or gastric varices were randomised to receive intravenous infusion of somatostatin (250 µg/hour) plus oral isosorbide 5-mononitrate (40 mg/12 hours) (group I) or somatostatin infusion plus placebo (group II) for 72 hours.
RESULTS—The two groups of patients had similar clinical, endoscopic, and haematological characteristics. Control of bleeding was achieved in 18 out of 30 patients (60%) in group I and 26 out of 30 patients (87%) in group II (p<0.05). There was no significant difference in mean transfusion requirements between the two groups: 2.6 (2.2) v 1.8 (1.6) respectively; means (SD). Mortality and side effects were similar in the two groups, but development of ascites was higher in group I (30%) than in group II (7%) (p<0.05).
CONCLUSION—In cirrhotic patients with acute gastro-oesophageal variceal bleeding, addition of isosorbide 5-mononitrate to somatostatin does not improve therapeutic efficacy, induces more adverse effects, and should not be used.


Keywords: gastro-oesophageal bleeding; haemorrhage; portal hypertension; clinical trial; isosorbide 5-mononitrate; somatostatin PMID:10601068

  7. Simultaneous bile duct and portal vein ligation induces faster atrophy/hypertrophy complex than portal vein ligation: role of bile acids

    PubMed Central

    Ren, Weizheng; Chen, Geng; Wang, Xiaofeng; Zhang, Aiqun; Li, Chonghui; Lv, Wenping; Pan, Ke; Dong, Jia-hong

    2015-01-01

    Portal vein ligation (PVL) induces atrophy/hypertrophy complex (AHC). We hypothesised that simultaneous bile duct and portal vein ligation (BPL) might induce proper bile acid (BA) retention to enhance AHC by activating BA-mediated FXR signalling in the intact liver and promoting apoptosis in the ligated liver. We established rat models of 90% BPL and 90% PVL and found that BPL was well-tolerated and significantly accelerated AHC. The enhanced BA retention in the intact liver promoted hepatocyte proliferation by promoting the activation of FXR signalling, while that in the ligated liver intensified caspase3-mediated apoptosis. Decreasing the BA pools in the rats that underwent BPL could compromise these effects, whereas increasing the bile acid pools of rats that underwent PVL could induce similar effects. Second-stage resection of posterior-caudate-lobe-spearing hepatectomy was performed 5 days after BPL (B-Hx), PVL (V-Hx) or sham (S-SHx), as well as whole-caudate-lobe-spearing hepatectomy 5 days after sham (S-Hx). The B-Hx group had the most favourable survival rate (93.3%, the S-SHx group 0%, the S-Hx group 26.7%, the V-Hx group 56.7%, P < 0.01) and the most sustained regeneration. We conclude that BPL is a safe and effective method, and the acceleration of AHC was bile acid-dependent. PMID:25678050

  8. Optimum level of inferior mesenteric artery ligation for the left-sided colorectal cancer

    PubMed Central

    Guraya, Salman Y.

    2016-01-01

    Objectives: To compares the effectiveness and impact of high inferior mesenteric artery (IMA) versus low IMA ligation on 5-year survival, lymph node yield rates, and peri-operative morbidity and mortality. Methods: The databases of Educational Resources Information Centre (ERIC), the Web of Science, EBSCO and MEDLINE were searched using MeSH terms ‘colorectal cancer’, ‘inferior mesenteric artery’, ‘high ligation’, ‘low ligation’, ‘mesenteric lymph nodes’, ‘prognosis’, and ‘survival’. Only clinical studies were selected and review articles and meta-analysis were excluded. In cases of duplicate cohorts, only the latest article was included. Irrelevant articles and the articles on both right and left sided CRC were excluded. The finally selected studies were analysed for the defined end-point outcomes. Results: The published data has shown that high IMA ligation improves the yield of harvested lymph node that allows accurate tumor staging and a more reliable estimation of prognosis. High ligation was not found to be positively correlated with increased anastomotic leakage or impaired genito-urinary function. However, high ligation demands advanced surgical expertise and longer operating time. There was no significant difference in 5-year survival rates for both techniques. Some studies have reported fatal complications of high ligation such as proximal bowel necrosis. Conclusion: Although there is no consensus, this research signals the routine use of high ligation for left-sided CRC. However, the published fatal complications following high ligation and no significant difference in 5-year survival rates demand more studies to establishing a unified protocol. PMID:27381531

  9. A Beginning or the End? A Meta-analysis to Assess the Diagnostic Accuracy of Transient Elastography for the Prediction of Esophageal Varices

    PubMed Central

    Qu, Yundong; Li, Tao; Ye, Qian; Zhang, Lixin; Wang, Lei

    2016-01-01

    Background/Aims: To assess the accuracy of transient elastography (TE) in the prediction of esophageal varices (EV). Materials and Methods: The literature search was conducted by using PubMed, EMBASE, Web of Science, and CENTRAL on The Cochrane Library without time or language restrictions. Terms used were “FibroScan,” “transient elastography,” “stiffness,” and “esophageal varices.” The pooled sensitivity, specificity, and other parameters were obtained using a bivariate mixed-effects regression model. Result: Twenty studies (2530 patients) were identified for inclusion. The pooled sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio were 0.84 (95% confidence interval [CI], 0.79–0.87), 0.68 (95% CI, 0.61–0.73), 2.58 (95% CI, 2.15–3.10), 0.24 (95% CI, 0.19–0.32), and 10.60 (95%CI, 7.20–15.62), respectively. The summary area under receiver operating characteristics (AUROC) curves was 0.82 (95% CI, 0.79–0.86). Especially, for hepatitis C patients, the diagnostic performance of TE for detecting the presence of EV was similar to all other patients with a sensitivity of 0.83 and a specificity of 0.63, but without heterogeneity (I2 = 0.00). For the prediction of large esophageal varices in patients with viral liver cirrhosis, the pooled sensitivity and specificity of TE were 0.82 (95% CI 0.74–0.89) and 0.77 (95% CI 0.65-0.85), respectively, without significant heterogeneity (I2 = 0.00). Conclusion: Transient elastography has good sensitivity and moderate specificity. TE can be used as an effective noninvasive screening tool for the prediction of esophageal varices, especially in hepatitis C patients, and for the prediction of large esophageal varices in patients with viral liver cirrhosis.

  10. Effects of double ligation of Stensen's duct on the rabbit parotid gland.

    PubMed

    Maria, O M; Maria, S M; Redman, R S; Maria, A M; Saad El-Din, T A; Soussa, E F; Tran, S D

    2014-04-01

    Salivary gland duct ligation is an alternative to gland excision for treating sialorrhea or reducing salivary gland size prior to tumor excision. Duct ligation also is used as an approach to study salivary gland aging, regeneration, radiotherapy, sialolithiasis and sialadenitis. Reports conflict about the contribution of each salivary cell population to gland size reduction after ductal ligation. Certain cell populations, especially acini, reportedly undergo atrophy, apoptosis and proliferation during reduction of gland size. Acini also have been reported to de-differentiate into ducts. These contradictory results have been attributed to different animal or salivary gland models, or to methods of ligation. We report here a bilateral double ligature technique for rabbit parotid glands with histologic observations at 1, 7, 14, 30, 60 days after ligation. A large battery of special stains and immunohistochemical procedures was employed to define the cell populations. Four stages with overlapping features were observed that led to progressive shutdown of gland activities: 1) marked atrophy of the acinar cells occurred by 14 days, 2) response to and removal of the secretory material trapped in the acinar and ductal lumens mainly between 30 and 60 days, 3) reduction in the number of parenchymal (mostly acinar) cells by apoptosis that occurred mainly between 14-30 days, and 4) maintenance of steady-state at 60 days with a low rate of fluid, protein, and glycoprotein secretion, which greatly decreased the number of leukocytes engaged in the removal of the luminal contents. The main post- ligation characteristics were dilation of ductal and acinar lumens, massive transient infiltration of mostly heterophils (rabbit polymorphonuclear leukocytes), acinar atrophy, and apoptosis of both acinar and ductal cells. Proliferation was uncommon except in the larger ducts. By 30 days, the distribution of myoepithelial cells had spread from exclusively investing the intercalated ducts

  11. The effect of pregabalin - codeine combination on partial sciatic nerve ligation - induced peripheral mononeuropathy in rats.

    PubMed

    Popa, G; Mititelu Tartau, L; Stoleriu, I; Lupusoru, R V; Lupusoru, C E; Ochiuz, L

    2016-06-01

    The present study investigates the effects of pregabalin (PGB) and codeine (COD) combination on neuropathic hyperalgesia in an animal model of peripheral nerve injury represented by partial sciatic nerve ligation. Hot plate and analgesimeter tests were performed to evaluate the influence of PGB, COD and their combination on thermal and mechanical hyperalgesia in the hind paw with partial sciatic nerve ligation. Reactivity was evaluated by measuring the latency to withdrawal of the operated hind paw from the noxious heat and pressure stimulation. Nociceptive thresholds were evaluated before (baseline) and in the 1(st), 3(rd), 5(th) and 7(th) day after surgical procedure. The investigation demonstrates that the treatment with PGB attenuated partial sciatic nerve ligation development of thermal and mechanical hyperalgesia in rats operated hind paw. The oral administration, during 14 consecutive days of PGB-COD combination significantly reduced the degree of both thermal and mechanical hyperalgesia in the hind paw with partial sciatic nerve ligation. These results suggest that the association of PGB with COD exerted ameliorative effect on partial sciatic nerve ligation-induced neuropathic pain in rats. PMID:27512007

  12. A Relaxed Active Site After Exon Ligation by the Group I Intron

    SciTech Connect

    Lipchock,S.; Strobel, S.

    2008-01-01

    During RNA maturation, the group I intron promotes two sequential phosphorotransfer reactions resulting in exon ligation and intron release. Here, we report the crystal structure of the intron in complex with spliced exons and two additional structures that examine the role of active-site metal ions during the second step of RNA splicing. These structures reveal a relaxed active site, in which direct metal coordination by the exons is lost after ligation, while other tertiary interactions are retained between the exon and the intron. Consistent with these structural observations, kinetic and thermodynamic measurements show that the scissile phosphate makes direct contact with metals in the ground state before exon ligation and in the transition state, but not after exon ligation. Despite no direct exonic interactions and even in the absence of the scissile phosphate, two metal ions remain bound within the active site. Together, these data suggest that release of the ligated exons from the intron is preceded by a change in substrate-metal coordination before tertiary hydrogen bonding contacts to the exons are broken.

  13. A comparison of self-ligating and conventional orthodontic bracket systems.

    PubMed

    Read-Ward, G E; Jones, S P; Davies, E H

    1997-11-01

    This ex-vivo study compared the static frictional resistance of three self-ligating brackets with a conventional steel-ligated Ultratrimm bracket. The effects of archwire size (0.020, 0.019 x 0.025 and 0.021 x 0.025-inch), bracket/archwire angulation (0, 5 and 10 degrees) and the presence of unstimulated human saliva were investigated. The study demonstrated that both increases in wire size and bracket/archwire angulation resulted in increased static frictional resistance for all bracket types tested, with the presence of saliva having an inconsistent effect. Mobil-Lock Variable-Slot had the least friction for all wires for 0 degree angulation. However, with the introduction of angulation, the values were comparable to those of the other brackets. Activa brackets had the second lowest frictional resistance, although high values were found with 0.019 x 0.025-inch wires. SPEED brackets demonstrated low forces with round wires, although with rectangular wires or in the presence of angulation, friction was greatly increased. Ultratrimm brackets produced large individual variation, confirming the difficulty in standardizing ligation force, although under certain conditions, significantly larger frictional forces were observed. In conclusion, self-ligating brackets showed reduced frictional resistance in comparison to steel ligated brackets only under certain conditions. PMID:9459030

  14. Effects of gabapentin on thermal sensitivity following spinal nerve ligation or spinal cord compression.

    PubMed

    Yezierski, Robert P; Green, Megan; Murphy, Karen; Vierck, Charles J

    2013-10-01

    Neuropathic pain challenges healthcare professionals and researchers to develop new strategies of treatment and experimental models to better understand the pathophysiology of this condition. In the present study, the efficacy of gabapentin on thermal sensitivity following spinal nerve ligation and spinal cord compression was evaluated. The method of behavioral assessment was a well-validated cortically dependent operant escape task. Spinal nerve ligation produced peripheral neuropathic pain whereas spinal cord compression, achieved with an expanding polymer placed extradurally, produced a condition of central neuropathic pain. Changes in thermal sensitivity were also observed in animals undergoing nerve ligation surgery without nerve injury. Gabapentin (50 and 100 mg/kg) significantly reduced thermal sensitivity to 10 and 44.5 °C in surgically naive animals as well as those undergoing spinal nerve ligation and spinal cord compression. In conclusion, an operant method of behavioral assessment was used to show that spinal nerve ligation and spinal cord compression produced increases in sensitivity to noxious cold and heat stimuli. A decrease in thermal sensitivity was observed following administration of gabapentin. The results achieved with these methods are consistent with the clinical profile of gabapentin in treating conditions of neuropathic pain.

  15. Controllable Mismatched Ligation for Bioluminescence Screening of Known and Unknown Mutations.

    PubMed

    Xu, Qinfeng; Huang, Si-qiang; Ma, Fei; Tang, Bo; Zhang, Chun-yang

    2016-02-16

    Single-nucleotide polymorphisms (SNPs) are closely related to human diseases and individual drug responses, and the accurate detection of SNPs is crucial to both clinical diagnosis and development of personalized medicine. Among various SNPs detection methods, ligase detection reaction (LDR) has shown great potential due to its low detection limit and excellent specificity. However, frequent involvement of expensive labels increases the experimental cost and compromises the assay efficiency, and the requirement of careful predesigned probes limits it to only known SNPs assays. In this research, we develop a controllable mismatched ligation for bioluminescence screening of both known and unknown mutations. Especially, the ligation specificity of E. coli ligase is tunable under different experimental conditions. The mismatches locating on the 3'-side of the nick cannot be ligated efficiently by E. coli ligase, whereas all mismatches locating on the 5'-side of the nick can be ligated efficiently by E. coli ligase. We design a 3'-discriminating probe (3'-probe) for the discrimination of known mutation and introduce a T7 Endo I for the detection of unknown mutation. With the integration of bioluminescence monitoring of ligation byproduct adenosine 5'-monophosphate (AMP), both known and unknown SNPs can be easily detected without the involvement of any expensive labels and labor-intensive separation. This method is simple, homogeneous, label-free, and cost-effective and may provide a valuable complement to current sequencing technologies for disease diagnostics, personalized medicine, and biomedical research. PMID:26754165

  16. Rapid and Efficient Production of Coronary Artery Ligation and Myocardial Infarction in Mice Using Surgical Clips

    PubMed Central

    Hensley, Michael Taylor; Vandergriff, Adam; Cores, Jhon; Henry, Eric; Allen, Tyler A.; Caranasos, Thomas George; Wang, Zegen; Zhang, Tianxia; Zhang, Jinying; Cheng, Ke

    2015-01-01

    Aims The coronary artery ligation model in rodents mimics human myocardial infarction (MI). Normally mechanical ventilation and prolonged anesthesia period are needed. Recently, a method has been developed to create MI by popping-out the heart (without ventilation) followed by immediate suture ligation. Mortality is high due to the time-consuming suture ligation process while the heart is exposed. We sought to improve this method and reduce mortality by rapid coronary ligation using a surgical clip instead of a suture. Methods and Results Mice were randomized into 3 groups: clip MI (CMI), suture MI (SMI), or sham (SHAM). In all groups, heart was manually exposed without intubation through a small incision on the chest wall. Unlike the conventional SMI method, mice in the CMI group received a metal clip on left anterior descending artery (LAD), quickly dispensed by an AutoSuture Surgiclip™. The CMI method took only 1/3 of ligation time of the standard SMI method and improved post-MI survival rate. TTC staining and Masson’s trichrome staining revealed a similar degree of infarct size in the SMI and CMI groups. Echocardiograph confirmed that both SMI and CMI groups had a similar reduction of ejection fraction and fraction shortening over the time. Histological analysis showed that the numbers of CD68+ macrophages and apoptotic cells (TUNEL-positive) are indistinguishable between the two groups. Conclusion This new method, taking only less than 3 minutes to complete, represents an efficient myocardial infarction model in rodents. PMID:26599500

  17. Realizing serine/threonine ligation: scope and limitations and mechanistic implication thereof

    PubMed Central

    Wong, Clarence T. T.; Li, Tianlu; Lam, Hiu Yung; Zhang, Yinfeng; Li, Xuechen

    2014-01-01

    Serine/Threonine ligation (STL) has emerged as an alternative tool for protein chemical synthesis, bioconjugations as well as macrocyclization of peptides of various sizes. Owning to the high abundance of Ser/Thr residues in natural peptides and proteins, STL is expected to find a wide range of applications in chemical biology research. Herein, we have fully investigated the compatibility of the STL strategy for X-Ser/Thr ligation sites, where X is any of the 20 naturally occurring amino acids. Our studies have shown that 17 amino acids are suitable for ligation, while Asp, Glu, and Lys are not compatible. Among the working 17 C-terminal amino acids, the retarded reaction resulted from the bulky β-branched amino acid (Thr, Val, and Ile) is not seen under the current ligation condition. We have also investigated the chemoselectivity involving the amino group of the internal lysine which may compete with the N-terminal Ser/Thr for reaction with the C-terminal salicylaldehyde (SAL) ester aldehyde group. The result suggested that the free internal amino group does not adversely slow down the ligation rate. PMID:24904921

  18. Sugar-Assisted Glycopeptide Ligation with Complex Oligosaccharides: Scope and Limitations

    PubMed Central

    Bennett, Clay S.; Dean, Stephen M.; Payne, Richard J.; Ficht, Simon; Brik, Ashraf

    2008-01-01

    We have previously shown sugar-assisted ligation (SAL) to be a useful method for the convergent construction of glycopeptides. However to date SAL has only been carried out on systems where the thiol auxiliary is attached to a monosaccharide. For SAL to be truly applicable to the construction of fully elaborated glycopeptides and glycoproteins it must be possible to carry out the reaction when the thiol auxiliary is attached to more elaborate sugars, as these are frequently what are observed in nature. Here we examine the effects of glycosylation at C-3, C-4 and C-6 of the C-2 auxiliary-containing glycan. Model glycopeptides where synthesized chemoenzymatically and reacted with peptide thioesters used in our previous work. These studies reveal that SAL is sensitive to extended glycosylation on the auxiliary-containing sugar. While it is possible to carry out SAL with extended glycosylation at C-4 and C-6, the presence of glycosylation at C-3 prevents the ligation from occurring. Additionally, with glycosylation at C-4 the ligation efficiency is affected by the identity of the N-terminal AA, while the nature of the C-terminal residue of the peptide thioester does not appear affect ligation efficiency. These studies provide useful guidelines in deciding when it is appropriate to use SAL in the synthesis of complex glycopeptides and glycoproteins, and how to design ligation junctions for optimal yield. PMID:18698778

  19. Technical considerations for ligation of ruptured hepatic artery aneurysm: is arterial reconstruction necessary?

    PubMed

    Lam, S; Chan, Albert C Y; Poon, Ronnie T P

    2015-06-01

    Ruptured hepatic artery aneurysm is a rare life-threatening condition. Open surgery with ligation of the aneurysm is the treatment of choice if the patient presents with haemodynamic instability. Controversies exist on whether hepatic artery reconstruction is needed after exclusion of the aneurysm. Involvement of the gastroduodenal artery origin was proposed as an indication for reconstruction, but this might be difficult to ascertain upon laparotomy. Recent studies showed that arterial ligation distal to the gastroduodenal artery origin does not necessarily result in ischaemic liver injury, implying that reconstruction in such cases may not be required, especially in a haemodynamically unstable patient. A patient with common hepatic artery aneurysm involving the gastroduodenal artery origin presented with rupture and underwent aneurysm ligation. Adequacy of intrahepatic arterial flow was determined by intra-operative Doppler ultrasonography and arterial reconstruction was not performed. The technical considerations during the operative management of ruptured hepatic artery aneurysms are discussed. PMID:26045071

  20. Expressed Protein Ligation: A Resourceful Tool to Study Protein Structure and Function

    PubMed Central

    Berrade, Luis; Camarero, Julio A.

    2013-01-01

    This review outlines the use of expressed protein ligation (EPL) to study protein structure, function and stability. EPL is a chemoselective ligation method that allows the selective ligation of unprotected polypeptides from synthetic and recombinant origin for the production of semi-synthetic protein samples of well-defined and homogeneous chemical composition. This method has been extensively used for the site-specific introduction of biophysical probes, unnatural amino acids, and increasingly complex post-translational modifications. Since it was introduced 10 years ago, EPL applications have grown increasingly more sophisticated in order to address even more complex biological questions. In this review we highlight how this powerful technology combined with standard biochemical analysis techniques has been used to improve our ability to understand protein structure and function. PMID:19685006

  1. Abiotic ligation of DNA oligomers templated by their liquid crystal ordering

    NASA Astrophysics Data System (ADS)

    Fraccia, Tommaso P.; Smith, Gregory P.; Zanchetta, Giuliano; Paraboschi, Elvezia; Yi, Yougwooo; Walba, David M.; Dieci, Giorgio; Clark, Noel A.; Bellini, Tommaso

    2015-03-01

    It has been observed that concentrated solutions of short DNA oligomers develop liquid crystal ordering as the result of a hierarchically structured supramolecular self-assembly. In mixtures of oligomers with various degree of complementarity, liquid crystal microdomains are formed via the selective aggregation of those oligomers that have a sufficient degree of duplexing and propensity for physical polymerization. Here we show that such domains act as fluid and permeable microreactors in which the order-stabilized molecular contacts between duplex terminals serve as physical templates for their chemical ligation. In the presence of abiotic condensing agents, liquid crystal ordering markedly enhances ligation efficacy, thereby enhancing its own phase stability. The coupling between order-templated ligation and selectivity provided by supramolecular ordering enables an autocatalytic cycle favouring the growth of DNA chains, up to biologically relevant lengths, from few-base long oligomers. This finding suggests a novel scenario for the abiotic origin of nucleic acids.

  2. RNA ligation in neurons by RtcB inhibits axon regeneration

    PubMed Central

    Kosmaczewski, Sara Guckian; Han, Sung Min; Han, Bingjie; Irving Meyer, Benjamin; Baig, Huma S.; Athar, Wardah; Lin-Moore, Alexander T.; Koelle, Michael R.; Hammarlund, Marc

    2015-01-01

    Activity of the RNA ligase RtcB has only two known functions: tRNA ligation after intron removal and XBP1 mRNA ligation during activation of the unfolded protein response. Here, we show that RtcB acts in neurons to inhibit axon regeneration after nerve injury. This function of RtcB is independent of its basal activities in tRNA ligation and the unfolded protein response. Furthermore, inhibition of axon regeneration is independent of the RtcB cofactor archease. Finally, RtcB is enriched at axon termini after nerve injury. Our data indicate that neurons have co-opted an ancient RNA modification mechanism to regulate specific and dynamic functions and identify neuronal RtcB activity as a critical regulator of neuronal growth potential. PMID:26100902

  3. Endoscopic injection sclerotherapy in non-variceal upper gastrointestinal bleeding. A comparative study of polidocanol and thrombin.

    PubMed

    Benedetti, G; Sablich, R; Lacchin, T

    1991-01-01

    To date several agents have been used to achieve haemostasis in patients with non-variceal upper gastrointestinal bleeding using endoscopic sclerotherapy techniques. Polidocanol has been widely used but local complications have been reported after treatment. We have compared the efficacy and safety of thrombin and polidocanol in 82 consecutive patients with ongoing or recent bleeding from duodenal, gastric, or anastomotic ulcers. Primary control of haemostasis from spurting vessels was achieved in 90% of cases using polidocanol and in 86.6% using thrombin. Definitive haemostasis was obtained in 80% of patients in both groups. When a non-bleeding vessel was visible, injection of polidocanol or thrombin effectively prevented rebleeding in 90.9% and 85.7% of cases, respectively. When a non-bleeding sentinel clot was present, injection of polidocanol or thrombin provided definitive haemostasis in 100% and 92.8% of cases, respectively. No statistically significant difference was evident between the two agents. In the polidocanol group, one local haemorrhagic complication was noted. No general or local complications were recorded in the thrombin group.

  4. Frictional resistance of self-ligating versus conventional brackets in different bracket-archwire-angle combinations

    PubMed Central

    MONTEIRO, Maria Regina Guerra; da SILVA, Licinio Esmeraldo; ELIAS, Carlos Nelson; VILELLA, Oswaldo de Vasconcellos

    2014-01-01

    Objective To compare the influence of archwire material (NiTi, beta-Ti and stainless steel) and brackets design (self-ligating and conventional) on the frictional force resistance. Material and Methods Two types of brackets (self-ligating brackets - Smartclip, 3M/Unitek - and conventional brackets - Gemini, 3M/Unitek) with three (0, 5, and 10 degrees) slot angulation attached with elastomeric ligatures (TP Orthodontics) were tested. All brackets were tested with archwire 0.019"x0.025" nickel-titanium, beta-titanium, and stainless steel (Unitek/3M). The mechanical testing was performed with a universal testing machine eMIC DL 10000 (eMIC Co, Brazil). The wires were pulled from the bracket slots at a cross-head speed of 3 mm/min until 2 mm displacement. Results Self-ligating brackets produced significantly lower friction values compared with those of conventional brackets. Frictional force resistance values were directly proportional to the increase in the bracket/ wire angulation. With regard to conventional brackets, stainless steel wires had the lowest friction force values, followed by nickel-titanium and beta-titanium ones. With regard to self-ligating brackets, the nickel-titanium wires had the lowest friction values, significantly lower than those of other materials. Conclusion even at different angulations, the self-ligating brackets showed significantly lower friction force values than the conventional brackets. Combined with nickel-titanium wires, the self-ligating brackets exhibit much lower friction, possibly due to the contact between nickel-titanium clips and wires of the same material. PMID:25025564

  5. Isolation of novel ribozymes that ligate AMP-activated RNA substrates

    NASA Technical Reports Server (NTRS)

    Hager, A. J.; Szostak, J. W.

    1997-01-01

    BACKGROUND: The protein enzymes RNA ligase and DNA ligase catalyze the ligation of nucleic acids via an adenosine-5'-5'-pyrophosphate 'capped' RNA or DNA intermediate. The activation of nucleic acid substrates by adenosine 5'-monophosphate (AMP) may be a vestige of 'RNA world' catalysis. AMP-activated ligation seems ideally suited for catalysis by ribozymes (RNA enzymes), because an RNA motif capable of tightly and specifically binding AMP has previously been isolated. RESULTS: We used in vitro selection and directed evolution to explore the ability of ribozymes to catalyze the template-directed ligation of AMP-activated RNAs. We subjected a pool of 10(15) RNA molecules, each consisting of long random sequences flanking a mutagenized adenosine triphosphate (ATP) aptamer, to ten rounds of in vitro selection, including three rounds involving mutagenic polymerase chain reaction. Selection was for the ligation of an oligonucleotide to the 5'-capped active pool RNA species. Many different ligase ribozymes were isolated; these ribozymes had rates of reaction up to 0.4 ligations per hour, corresponding to rate accelerations of approximately 5 x10(5) over the templated, but otherwise uncatalyzed, background reaction rate. Three characterized ribozymes catalyzed the formation of 3'-5'-phosphodiester bonds and were highly specific for activation by AMP at the ligation site. CONCLUSIONS: The existence of a new class of ligase ribozymes is consistent with the hypothesis that the unusual mechanism of the biological ligases resulted from a conservation of mechanism during an evolutionary replacement of a primordial ribozyme ligase by a more modern protein enzyme. The newly isolated ligase ribozymes may also provide a starting point for the isolation of ribozymes that catalyze the polymerization of AMP-activated oligonucleotides or mononucleotides, which might have been the prebiotic analogs of nucleoside triphosphates.

  6. Chronic heart failure model with sequential ligation of the homonymous artery and its diagonal branch in the sheep.

    PubMed

    Kim, W G; Park, J J; Oh, S I

    2001-01-01

    We report a reliable chronic heart failure model in sheep using sequential ligation of the homonymous artery and its diagonal branch. After a left anterior thoracotomy in Corridale sheep, the homonymous artery was ligated at a point approximately 40% of the distance from the apex to the base of the heart, and after 1 hour, the diagonal vessel was ligated at a point at the same level. Hemodynamic measurements were done preligation, 30 minutes after the homonymous artery ligation, and 1 hour after diagonal branch ligation. The electrocardiograms were obtained as needed, and cardiac function was also evaluated with ultrasonography. After a predetermined interval (2 months for five animals and 3 months for two animals), the animals were reevaluated in the same way as before, and were killed for postmortem examination of their hearts. All seven animals survived the experimental procedures. Statistically significant decreases in systemic arterial blood pressure and cardiac output and increases in pulmonary artery capillary wedge pressure were observed 1 hour after sequential ligation of the homonymous artery and its diagonal branch. Untrasonographic analyses demonstrated variable degrees of anteroseptal dyskinesia and akinesia in all animals. The data from animals at 2 months after coronary artery ligation showed significant increases in central venous pressure, pulmonary artery pressure, and pulmonary artery capillary wedge pressure. Left ventricular enddiastolic dimension and left ventricular end-systolic dimension on ultrasonographic studies were also increased. Electrocardiography showed severe ST elevation immediately after the ligation and pathologic Q waves were found at 2 months after ligation. The thin walled infarcted areas with chamber enlargement were clearly seen in the hearts removed at 2 and 3 months after ligation. In conclusion, we could achieve a reliable ovine model of chronic heart failure using a simple concept of sequential ligation of the

  7. Proline-based Phosphoramidite Reagents for the Reductive Ligation of S-Nitrosothiols

    PubMed Central

    Xian, Ming

    2015-01-01

    S-Nitrosothiols have many biological implications but are rarely used in organic synthesis. In this work we report the development of proline-based phosphoramidite substrates that can effectively convert S-nitrosothiols to proline-based sulfenamides through a reductive ligation process. A unique property of this method is that the phosphine oxide moiety on the ligation products can be readily removed under acidic conditions. In conjugation with the facile preparation of S-nitrosothiols (RSNO) from the corresponding thiols (RSH), this method provides a new way to prepare proline-based sulfenamides from simple thiol starting materials. PMID:26758493

  8. Enzymatic Ligation Creates Discrete Multi-Nanoparticle Building Blocks for Self-Assembly

    SciTech Connect

    Claridge, Shelley A.; Mastroianni, Alexander J.; Au, Yeung B.; Liang, Huiyang W.; Micheel, Christine M.; Frechet, Jean M.J.; Alivisatos, A. Paul

    2008-05-27

    Enzymatic ligation of discrete nanoparticle?DNA conjugates creates nanoparticle dimer and trimer structures in which the nanoparticles are linked by single-stranded DNA, rather than double-stranded DNA as in previous experiments. Ligation is verified by agarose gel and small-angle X-ray scattering. This capability is utilized in two ways: first to create a new class of multiparticle building blocks for nanoscale self-assembly; second to develop a system which can amplify a population of discrete nanoparticle assemblies.

  9. A novel post-ligation thioesterification device enables peptide ligation in the N to C direction: synthetic study of human glycodelin.

    PubMed

    Takenouchi, Takaomi; Katayama, Hidekazu; Nakahara, Yuko; Nakahara, Yoshiaki; Hojo, Hironobu

    2014-01-01

    Human glycodelin consists of 162 amino acid residues and two N-linked glycans at Asn(28) and Asn(63) . In this study, we synthesized it by a fully convergent strategy using native chemical ligation (NCL) in N to C direction. The four peptide segments corresponding to 1-31, 32-65, 66-105 and 106-162 sequences were synthesized by 9-fluorenylmethoxycarbonyl based solid-phase peptide synthesis. At the C-terminus of the second segment, N-ethyl-S-acetamidomethyl-cysteine was attached as a post-ligation thioesterification device. The N-terminal two segments were condensed by the homocysteine-mediated NCL at Leu-Met site, and the product was methylated to convert homocysteine to methionine. After deprotection of acetamidomethyl group on the N-ethylcysteine residue, the peptide was thioesterified by N-alkylcysteine-assisted method. The product was then ligated with the C-terminal half, which was obtained by the NCL of third and fourth segments, to give the full-length glycodelin.

  10. Balloon-occluded antegrade transvenous obliteration with or without balloon-occluded retrograde transvenous obliteration for the management of gastric varices: concept and technical applications.

    PubMed

    Saad, Wael E A; Kitanosono, Takashi; Koizumi, Jun

    2012-09-01

    Alternative routes for transvenous obliteration are sometimes resorted in the management of gastric varices. These alternative routes can be classified into A, portal venous access routes and B, systemic venous access routes. The portal venous approach to transvenous obliteration is called balloon-occluded antegrade transvenous obliteration (BATO) and is a collective definition, including 1-percutaneous transhepatic obliteration (PTO), 2-through an existing transjugular intrahepatic portosystemic shunt [(Trans-TIPS), and 3-trans-iliocolic vein obliteration (TIO)]. PTO is usually out of necessity; however, trans-TIPS approach is usually used out of serendipity (because the low-risk access route is there). The TIPS for the trans-TIPS BATO is not formed for mere access, but is done to create a TIPS or is done when there is a preexisting TIPS. The trans-TIPS approach can be resorted to in the United States in up to 19% of balloon-occluded retrograde transvenous obliteration (BRTO) cases. PTO is resorted to, out of necessity, in the United States and Japan in 10% of BRTO cases (2%-19% of BRTO cases) and can increase the technical and obliterative success rate of the transvenous obliteration procedure from 84%-98% to 98%-100%. The advantage of BATO as an adjunct to BRTO (combining a BRTO and BATO approach to obliterate the gastric varices) is not only limited to increasing the technical success rate of the obliterative procedure. BATO reduces the risk of overspill of the sclerosant from the gastric variceal system into the portal vein. Moreover, if the BATO is performed from a trans-TIPS approach, any overspill of the sclerosant mixture will partly (if not mostly) go through the patent TIPS to the systemic circulation (lung) rather than the intrahepatic portal vein branches (prevent portal vein embolization). This article discusses the clinical and technical applications, technical considerations, and the outcomes of BATO. PMID:23021832

  11. Diagnostic Accuracy of APRI, AAR, FIB-4, FI, and King Scores for Diagnosis of Esophageal Varices in Liver Cirrhosis: A Retrospective Study.

    PubMed

    Deng, Han; Qi, Xingshun; Peng, Ying; Li, Jing; Li, Hongyu; Zhang, Yongguo; Liu, Xu; Sun, Xiaolin; Guo, Xiaozhong

    2015-12-20

    BACKGROUND Aspartate aminotransferase-to-platelet ratio index (APRI), aspartate aminotransferase-to-alanine aminotransferase ratio (AAR), FIB-4, fibrosis index (FI), and King scores might be alternatives to the use of upper gastrointestinal endoscopy for the diagnosis of esophageal varices (EVs) in liver cirrhosis. This study aimed to evaluate their diagnostic accuracy in predicting the presence and severity of EVs in liver cirrhosis. MATERIAL AND METHODS All patients who were consecutively admitted to our hospital and underwent upper gastrointestinal endoscopy between January 2012 and June 2014 were eligible for this retrospective study. Areas under curve (AUCs) were calculated. Subgroup analyses were performed according to the history of upper gastrointestinal bleeding (UGIB) and splenectomy. RESULTS A total of 650 patients with liver cirrhosis were included, and 81.4% of them had moderate-severe EVs. In the overall analysis, the AUCs of these non-invasive scores for predicting moderate-severe EVs and presence of any EVs were 0.506-0.6 and 0.539-0.612, respectively. In the subgroup analysis of patients without UGIB, their AUCs for predicting moderate-severe varices and presence of any EVs were 0.601-0.664 and 0.596-0.662, respectively. In the subgroup analysis of patients without UGIB or splenectomy, their AUCs for predicting moderate-severe varices and presence of any EVs were 0.627-0.69 and 0.607-0.692, respectively. CONCLUSIONS APRI, AAR, FIB-4, FI, and King scores had modest diagnostic accuracy of EVs in liver cirrhosis. They might not be able to replace the utility of upper gastrointestinal endoscopy for the diagnosis of EVs in liver cirrhosis.

  12. A label-free electrochemiluminescent sensor for ATP detection based on ATP-dependent ligation.

    PubMed

    Zhao, Tingting; Lin, Chunshui; Yao, Qiuhong; Chen, Xi

    2016-07-01

    In this work, we describe a new label-free, sensitive and highly selective strategy for the electrochemiluminescent (ECL) detection of ATP at the picomolar level via ATP-induced ligation. The molecular-beacon like DNA probes (P12 complex) are self-assembled on a gold electrode. The presence of ATP leads to the ligation of P12 complex which blocks the digestion by Exonuclease III (Exo III). The protected P12 complex causes the intercalation of numerous ECL indicators (Ru(phen)3(2+)) into the duplex DNA grooves, resulting in significantly amplified ECL signal output. Since the ligating site of T4 DNA ligase and the nicking site of Exo III are the same, it involves no long time of incubation for conformation change. The proposed strategy combines the amplification power of enzyme and the inherent high sensitivity of the ECL technique and enables picomolar detection of ATP. The developed strategy also shows high selectivity against ATP analogs, which makes our new label-free and highly sensitive ligation-based method a useful addition to the amplified ATP detection arena. PMID:27154705

  13. Comparative clinical evaluation of Kshara Sutra ligation and hemorrhoidectomy in Arsha (hemorrhoids).

    PubMed

    Gupta, Meva Lal; Gupta, S K; Bhuyan, Chaturbhuja

    2011-04-01

    Arsha (hemorrhoids) is engorgement of the hemorrhoidal venous plexus, characterized by bleeding per rectum, constipation, pain, prolapse and discharge. It is manifested due to improper diet, prolonged standing and faulty habits of defecation causing derangement of tridosha, mainly vata dosha. Vitiated dosha localizes in guda vali, pradhana dhamani and mansdhara kala and vitiates twak, mansa, meda and rakta, resulting in the annavaha sroto dushti. Modern management of arsha needs, mainly, a surgical approach, i.e. hemorrhoidectomy, wherein the result was found to be less satisfactory. In this regard, to determine a solution for satisfactory cure, the kshara sutra ligation method in arsha was studied in comparison with hemarrhoidectomy. Kshara sutra ligation in arsha was employed in 35 patients, and 26 patients were dealt with hemorrhoidectomy. The study revealed a better result of the kshara sutra ligation-treated group in comparison with hemorrhoidectomy. The observations revealed that maximum advantages like minimum hospital stay, no bleeding during or after operation, no post-operative anal stenosis, a low cost-effective and more acceptable to different categories of people, etc. were recorded in the kshara sutra-treated group. Statistically, kshara sutra ligation for arsha was found to be highly significant and effective management. No adverse effects were noted during the follow-up period. PMID:22408307

  14. Mechanism of ubiquitin ligation and lysine prioritization by a HECT E3

    PubMed Central

    Kamadurai, Hari B; Qiu, Yu; Deng, Alan; Harrison, Joseph S; MacDonald, Chris; Actis, Marcelo; Rodrigues, Patrick; Miller, Darcie J; Souphron, Judith; Lewis, Steven M; Kurinov, Igor; Fujii, Naoaki; Hammel, Michal; Piper, Robert; Kuhlman, Brian; Schulman, Brenda A

    2013-01-01

    Ubiquitination by HECT E3 enzymes regulates myriad processes, including tumor suppression, transcription, protein trafficking, and degradation. HECT E3s use a two-step mechanism to ligate ubiquitin to target proteins. The first step is guided by interactions between the catalytic HECT domain and the E2∼ubiquitin intermediate, which promote formation of a transient, thioester-bonded HECT∼ubiquitin intermediate. Here we report that the second step of ligation is mediated by a distinct catalytic architecture established by both the HECT E3 and its covalently linked ubiquitin. The structure of a chemically trapped proxy for an E3∼ubiquitin-substrate intermediate reveals three-way interactions between ubiquitin and the bilobal HECT domain orienting the E3∼ubiquitin thioester bond for ligation, and restricting the location of the substrate-binding domain to prioritize target lysines for ubiquitination. The data allow visualization of an E2-to-E3-to-substrate ubiquitin transfer cascade, and show how HECT-specific ubiquitin interactions driving multiple reactions are repurposed by a major E3 conformational change to promote ligation. DOI: http://dx.doi.org/10.7554/eLife.00828.001 PMID:23936628

  15. Histamine receptors expressed in circulating progenitor cells have reciprocal actions in ligation-induced arteriosclerosis.

    PubMed

    Yamada, Sohsuke; Wang, Ke-Yong; Tanimoto, Akihide; Guo, Xin; Nabeshima, Atsunori; Watanabe, Takeshi; Sasaguri, Yasuyuki

    2013-09-01

    Histamine is synthesized as a low-molecular-weight amine from L-histidine by histidine decarboxylase (HDC). Recently, we demonstrated that carotid artery-ligated HDC gene-deficient mice (HDC(-/-)) showed less neointimal formation than wild-type (WT) mice, indicating that histamine participates in the process of arteriosclerosis. However, little is known about the roles of histamine-specific receptors (HHRs) in arteriosclerosis. To define the roles of HHRs in arteriosclerosis, we investigated intimal remodeling in ligated carotid arteries of HHR-deficient mice (H1R(-/-) or H2R(-/-)). Quantitative analysis showed that H1R(-/-) mice had significantly less arteriosclerogenesis, whereas H2R(-/-) mice had more, as compared with WT mice. Bone marrow transplantation from H1R(-/-) or H2R(-/-) to WT mice confirmed the above observation. Furthermore, the increased expression of monocyte chemoattractant protein (MCP-1), platelet-derived growth factor (PDGF), adhesion molecules and liver X receptor (LXR)-related inflammatory signaling factors, including Toll-like receptor (TLR3), interleukin-1 receptor (IL-1R) and tumor necrosis factor receptor (TNF-R), was consistent with the arteriosclerotic phenotype of H2R(-/-) mice. Peripheral progenitor cells in H2R(-/-) mice accelerate ligation-induced arteriosclerosis through their regulation of MCP-1, PDGF, adhesion molecules and LXR-related inflammatory signaling factors. In contrast, peripheral progenitor cells act to suppress arteriosclerosis in H1R(-/-) mice, indicating that HHRs reciprocally regulate inflammation in the ligation-induced arteriosclerosis.

  16. Principles and applications of Ligation Mediated PCR methods for DNA-based typing of microbial organisms.

    PubMed

    Krawczyk, Beata; Kur, Józef; Stojowska-Swędrzyńska, Karolina; Śpibida, Marta

    2016-01-01

    A significant number of DNA-based techniques has been introduced into the field of microorganisms' characterization and taxonomy. These genomic fingerprinting methods were developed to detect DNA sequence polymorphisms by using general principles, such as restriction endonuclease analysis, molecular hybridization, and PCR amplification. In recent years, some alternative techniques based on ligation of oligonucleotide adapters before DNA amplification by PCR, known as Ligation-Mediated PCR methods (LM PCR), have been successfully applied for the typing of microorganisms below the species level. These molecular methods include: Amplified Fragment Length Polymorphism (AFLP), Amplification of DNA fragments Surrounding Rare Restriction Sites (ADSRRS), PCR Melting Profiles (PCR MP), Ligation Mediated PCR/Shifter (LM PCR/Shifter), Infrequent-Restriction-Site Amplification (IRS PCR), double digestion Ligation Mediated Suppression PCR (ddLMS PCR). These techniques are now applied more and more often because they involve less time, are comparably inexpensive, and require only standard lab equipment. Here, we present a general review of this group of methods showing their possibilities and limitations. We also identify questions and propose solutions which may be helpful in choosing a particular LM PCR method for the achievement of the required goal.

  17. The course and nature of acinar cell death following pancreatic ligation in the guinea pig.

    PubMed Central

    Zeligs, J. D.; Janoff, A.; Dumont, A. E.

    1975-01-01

    The course and nature of acinar cell death (ACD) following pancreatic ligation in the guinea pig was studied as a possible model for human disease. Ultrastructural studies after various periods of ligation suggested a biphasic pattern of ACD. Early phase ACD involved only a small portion of acinar cells and occurred within a few hours of ligation. It was preceded by swelling and vesiculation of the rough endoplasmic reticulum. Morphometric measurements disclosed celular swelling at this time, and NaCl equilibration studies demonstrated a change in cellular osmoregulation. Late phase ACD, characterized by cellular wasting and autophagic vacuole formation, became prominent several days after ligation. Marked increases in lysosomal enzyme activities were found in tissue homogenates at this time, and acid phosphatase electron histochemistry localized the majority of this increased activity to lysosomes and autophagic vacuoles within the acinar cells. The etiology and nature of both phases of ACD are discussed. Images Figure 5 Figure 6 Figure 12 Figure 7 Figure 8 Figure 1 Figure 2 Figure 9 Figure 10 Figure 11 Figure 3 Figure 4 PMID:169698

  18. One-Step Ligation on RNA Amplification for the Detection of Point Mutations.

    PubMed

    Zhang, Lei; Wang, Jingjing; Coetzer, Mia; Angione, Stephanie; Kantor, Rami; Tripathi, Anubhav

    2015-11-01

    The detection of point mutations is required in the diagnosis of many human diseases. The conformal specificity of DNA ligases was elegantly used to distinguish single-nucleotide mismatches. However, to detect point mutations in RNA retroviruses, conventional ligase-mediated approaches require the reverse transcription of viral genomes before separate ligation and amplification steps. We developed one-step ligation on RNA amplification (LRA) for the direct detection of RNA point mutations. The process combines the ligase-mediated joining of two oligonucleotides and subsequent hot start amplification into a single-tube reaction. We report that modifications to the structure of the oligonucleotide ligation probes improve the rate of ligation and the specificity of mutation detection on RNA. We applied LRA to the detection of a common, clinically relevant HIV-1 reverse transcriptase drug-resistant point mutation, K103N, and compared it with allele-specific PCR and pyrosequencing. LRA achieved a limit of specific quantitation of 1:100 (1%), and a limit of specific detection for mutant K103N RNA transcripts among excess wild-type strands of 1:10,000 (0.01%). LRA also exhibited good detection threshold of 5 × 10(2) copies/μL K103N RNA transcripts. LRA is a novel point mutation detection method, with potential utilization in HIV drug resistance detection and early diagnostics of genetic disorders associated with other infectious diseases and cancer. PMID:26322949

  19. Templating effect in DNA proximity ligation enables use of non-bioorthogonal chemistry in biological fluids.

    PubMed

    Spiropulos, Nicholas G; Heemstra, Jennifer M

    2012-07-01

    Here we describe the first example of selective reductive amination in biological fluids using split aptamer proximity ligation (StAPL). Utilizing the cocaine split aptamer, we demonstrate small-molecule-dependent ligation that is dose-dependent over a wide range of target concentrations in buffer, human blood serum and artificial urine medium. We explore the substrate binding preferences of the split aptamer and find that the cinchona alkaloids quinine and quinidine bind to the aptamer with higher affinity than cocaine. This increased affinity leads to improved detection limits for these small-molecule targets. We also demonstrate that linker length and hydrophobicity impact the efficiency of split aptamer ligation. The ability to carry out selective chemical transformations using non-bioorthogonal chemistry in media where competing reactive groups are present highlights the power of the increased effective molarity provided by DNA assembly. Obviating the need for bioorthogonal chemistry would dramatically expand the repertoire of chemical transformations available for use in templated reactions such as proximity ligation assays, in turn enabling the development of novel methods for biomolecule detection.

  20. Templating effect in DNA proximity ligation enables use of non-bioorthogonal chemistry in biological fluids

    PubMed Central

    Spiropulos, Nicholas G.; Heemstra, Jennifer M.

    2012-01-01

    Here we describe the first example of selective reductive amination in biological fluids using split aptamer proximity ligation (StAPL). Utilizing the cocaine split aptamer, we demonstrate small-molecule-dependent ligation that is dose-dependent over a wide range of target concentrations in buffer, human blood serum and artificial urine medium. We explore the substrate binding preferences of the split aptamer and find that the cinchona alkaloids quinine and quinidine bind to the aptamer with higher affinity than cocaine. This increased affinity leads to improved detection limits for these small-molecule targets. We also demonstrate that linker length and hydrophobicity impact the efficiency of split aptamer ligation. The ability to carry out selective chemical transformations using non-bioorthogonal chemistry in media where competing reactive groups are present highlights the power of the increased effective molarity provided by DNA assembly. Obviating the need for bioorthogonal chemistry would dramatically expand the repertoire of chemical transformations available for use in templated reactions such as proximity ligation assays, in turn enabling the development of novel methods for biomolecule detection. PMID:23370267

  1. SYNTHESIS OF PROTEINS BY NATIVE CHEMICAL LIGATION USING FMOC-BASED CHEMISTRY

    SciTech Connect

    Camarero, J A; Mitchell, A R

    2005-01-20

    C-terminal peptide {alpha}-thioesters are valuable intermediates in the synthesis/semisynthesis of proteins by native chemical ligation. They are prepared either by solid-phase peptide synthesis (SPPS) or biosynthetically by protein splicing techniques. The present paper reviews the different methods available for the chemical synthesis of peptide {alpha}-thioesters using Fmoc-based SPPS.

  2. Gingival response in orthodontic patients: Comparative study between self-ligating and conventional brackets.

    PubMed

    Folco, Alejandra A; Benítez-Rogé, Sandra C; Iglesias, Marina; Calabrese, Diana; Pelizardi, Cristina; Rosa, Alcira; Brusca, Marisa I; Hecht, Pedro; Mateu, María E

    2014-01-01

    Orthodontic brackets contribute to the accumulation of bacterial plaque on tooth surfaces because they hinder oral hygiene. In contrast to conventional brackets, self-ligating brackets do not require additional parts to support the arches, thus improving dental hygiene. The aim of this study was to compare the gingival response in orthodontic patients wearing self-ligating or conventional brackets. A sample of 22 patients aged 16 to 30 years was divided into two groups: Group A, treated with selfligating brackets (Damon system) and Group B, treated with conventional brackets (Roth technique). The following were assessed during the treatment: Plaque Index (PI), Gingival Index (GI) and Probing Depth (PD), and sub-gingival samples were taken from teeth 14/24 for microbiological observation. No statistically significant difference was found between Groups A and B; p>0.05 (sign-ranked) or between PI, GI and PD at the different times (Friedman's Analysis of Variance), even though the indices were found to increase at 14 days, particularly for self-ligating brackets. The quantity and quality of microorganisms present were compatible with health on days 0, 28 and 56. As from day 14 there is a predominance of microbiota compatible with gingivitis in both groups. In the samples studied, orthodontic treatment increases bacterial plaque and inflammatory gingival response, but gingival-periodontal health can be maintained with adequate basic therapy. Self-ligating and conventional brackets produced similar gingival response. PMID:25560690

  3. Nucleotide sequence and newly formed phosphodiester bond of spontaneously ligated satellite tobacco ringspot virus RNA.

    PubMed Central

    Buzayan, J M; Hampel, A; Bruening, G

    1986-01-01

    The satellite RNA of tobacco ringspot virus (STobRV RNA) replicates and becomes encapsidated in association with tobacco ringspot virus. Previous results show that the infected tissue produces multimeric STobRV RNAs of both polarities. RNA that is complementary to encapsidated STobRV RNA, designated as having the (-) polarity, cleaves autolytically at a specific ApG bond. Purified autolysis products spontaneously join in a non-enzymic reaction. We report characteristics of this RNA ligation reaction: the terminal groups that react, the type of bond in the newly formed junction and the nucleotide sequence of the joined RNA. The nucleotide sequence of the ligated RNA shows that joining of the reacting RNAs restored an ApG bond. The junction ApG has a 3'-to-5' phosphodiester bond. Thus the net ligation reaction of STobRV (-)RNA is the precise reversal of autolysis. We discuss this new type of RNA ligation reaction and its implications for the formation of multimeric STobRV RNAs during replication. Images PMID:2433680

  4. Development of a (11)C-labeled tetrazine for rapid tetrazine-trans-cyclooctene ligation.

    PubMed

    Herth, Matthias M; Andersen, Valdemar L; Lehel, Szabolcs; Madsen, Jacob; Knudsen, Gitte M; Kristensen, Jesper L

    2013-05-01

    Tetrazine-trans-cyclooctene ligations are remarkably fast and selective reactions even at low micro-molar concentrations. In bioorthogonal radiochemistry, tools that enable conjugation of radioactive probes to pre-targeted vectors are of great interest. Herein, we describe the successful development of the first (11)C-labelled tetrazine and its reaction with trans-cyclooctenol.

  5. Impact of splenic artery ligation after major hepatectomy on liver function, regeneration and viability

    PubMed Central

    Carrapita, Jorge; Abrantes, Ana Margarida; Campelos, Sofia; Gonçalves, Ana Cristina; Cardoso, Dulce; Sarmento-Ribeiro, Ana Bela; Rocha, Clara; Santos, Jorge Nunes; Botelho, Maria Filomena; Tralhão, José Guilherme; Farges, Olivier; Barbosa, Jorge Maciel

    2016-01-01

    It was reported that prevention of acute portal overpressure in small-for-size livers by inflow modulation results in a better postoperative outcome. The aim is to investigate the impact of portal blood flow reduction by splenic artery ligation after major hepatectomy in a murine model. Forty-eight rats were subjected to an 85% hepatectomy or 85% hepatectomy and splenic artery ligation. Both groups were evaluated at 24, 48, 72 and 120 post-operative hours: liver function, regeneration and viability. All methods and experiments were carried out in accordance with Coimbra University guidelines. Splenic artery ligation produces viability increase after 24 h, induces a relative decrease in oxidative stress during the first 48 hours, allows antioxidant capacity increment after 24 h, which is reflected in a decrease of half-time normalized liver curve at 48 h and at 72 h and in an increase of mitotic index between 48 h and 72 h. Splenic artery ligation combined with 85% hepatectomy in a murine model, allows portal inflow modulation, promoting an increase in hepatocellular viability and regeneration, without impairing the function, probably by inducing a less marked elevation of oxidative stress at first 48 hours. PMID:27725728

  6. Comparative Study of Proton Pump Inhibitors on Dexamethasone Plus Pylorus Ligation Induced Ulcer Model in Rats

    PubMed Central

    Thippeswamy, A. H. M.; Sajjan, M.; Palkar, M. B.; Koti, B. C.; Viswanathaswamy, A. H. M.

    2010-01-01

    The present study was designed to compare ulcer protective effect of proton pump inhibitors viz. omeprazole, rabeprazole and lansoprazole against dexamethasone plus pylorus ligation induced ulcer model. Dexamethasone (5 mg/kg) was used as an ulcerogen. Dexamethasone suspended in 1% CMC in water was given orally to all the rats 15 min after the pylorus ligation. Omeprazole (20 mg/kg), rabeprazole (20 mg/kg), and lansoprazole (20 mg/kg) were administered by oral route 30 min prior to ligation was used for ulcer protective studies, gastric secretion and mucosal studies. Effects of proton pump inhibitors were determined by the evaluation of various biochemical parameters such as ulcer index, free and total acidity, gastric pH, mucin, pepsin and total proteins. Oral administration of proton pump inhibitors showed significant reduction in gastric acid secretion and ulcer protective activity against dexamethasone plus pylorus ligation induced ulcer model. The % protection of omeprazole, rabeprazole and lansoprazole was 84.04, 89.36 and 79.78, respectively. Rabeprazole significantly inhibited the acid-pepsin secretion and increased the gastric mucin secretion. The observations made in the present study suggest that rabeprazole is the most effective gastric antisecretory and ulcer healing agent as compared to omeprazole and lansoprazole. PMID:21188049

  7. Principles and applications of Ligation Mediated PCR methods for DNA-based typing of microbial organisms.

    PubMed

    Krawczyk, Beata; Kur, Józef; Stojowska-Swędrzyńska, Karolina; Śpibida, Marta

    2016-01-01

    A significant number of DNA-based techniques has been introduced into the field of microorganisms' characterization and taxonomy. These genomic fingerprinting methods were developed to detect DNA sequence polymorphisms by using general principles, such as restriction endonuclease analysis, molecular hybridization, and PCR amplification. In recent years, some alternative techniques based on ligation of oligonucleotide adapters before DNA amplification by PCR, known as Ligation-Mediated PCR methods (LM PCR), have been successfully applied for the typing of microorganisms below the species level. These molecular methods include: Amplified Fragment Length Polymorphism (AFLP), Amplification of DNA fragments Surrounding Rare Restriction Sites (ADSRRS), PCR Melting Profiles (PCR MP), Ligation Mediated PCR/Shifter (LM PCR/Shifter), Infrequent-Restriction-Site Amplification (IRS PCR), double digestion Ligation Mediated Suppression PCR (ddLMS PCR). These techniques are now applied more and more often because they involve less time, are comparably inexpensive, and require only standard lab equipment. Here, we present a general review of this group of methods showing their possibilities and limitations. We also identify questions and propose solutions which may be helpful in choosing a particular LM PCR method for the achievement of the required goal. PMID:26885774

  8. Self-ligating versus Invisalign: analysis of dento-alveolar effects

    PubMed Central

    Pavoni, Chiara; Lione, Roberta; Laganà, Giuseppina; Cozza, Paola

    2011-01-01

    Summary Aim The aim of this study was to evaluate the changes in the transverse dimension and the perimeter of the maxillary arch produced by low friction self-ligating brackets TIME 3 compared to the Invisalign technique. Materials and methods Both the self-ligating sample and the Invisalign group were composed of 20 subjects, evaluated at the beginning (T0) and at the completion of therapy (T1). All subjects presented a Class I malocclusion with mild crowding in a permanent dentition, without craniofacial anomalies, missing teeth or a history of orthodontic treatment. Dento-alveolar measurements were made on the maxillary dental casts at T0 and T1. Significant differences between the treated groups were assessed with Independent Samples t test (p<0.05). Results Statistically significant differences between self-ligating sample and Invisalign group were recorded for CWC, FPWF, FPWL, SPWF, SPWL, and AP measurements. No significant changes were found for CWL, MWF, MWL, and AD values. There was not a statistically significant difference between the treatment durations of the groups: 1.8 years for both patients. These data suggest that Invisalign treatment cannot be somewhat faster than fixed appliances. Moreover the final occlusion might not be as ideal. Conclusions The low fiction self-ligating system produced statistically significant different outcomes in the transverse dento-alveolar width and the perimeter of the maxillary arch during treatment when compared to Invisalign tecnique. PMID:22238719

  9. A label-free electrochemiluminescent sensor for ATP detection based on ATP-dependent ligation.

    PubMed

    Zhao, Tingting; Lin, Chunshui; Yao, Qiuhong; Chen, Xi

    2016-07-01

    In this work, we describe a new label-free, sensitive and highly selective strategy for the electrochemiluminescent (ECL) detection of ATP at the picomolar level via ATP-induced ligation. The molecular-beacon like DNA probes (P12 complex) are self-assembled on a gold electrode. The presence of ATP leads to the ligation of P12 complex which blocks the digestion by Exonuclease III (Exo III). The protected P12 complex causes the intercalation of numerous ECL indicators (Ru(phen)3(2+)) into the duplex DNA grooves, resulting in significantly amplified ECL signal output. Since the ligating site of T4 DNA ligase and the nicking site of Exo III are the same, it involves no long time of incubation for conformation change. The proposed strategy combines the amplification power of enzyme and the inherent high sensitivity of the ECL technique and enables picomolar detection of ATP. The developed strategy also shows high selectivity against ATP analogs, which makes our new label-free and highly sensitive ligation-based method a useful addition to the amplified ATP detection arena.

  10. Single universal primer multiplex ligation-dependent probe amplification with sequencing gel electrophoresis analysis.

    PubMed

    Shang, Ying; Zhu, Pengyu; Xu, Wentao; Guo, Tianxiao; Tian, Wenying; Luo, Yunbo; Huang, Kunlun

    2013-12-15

    In this study, a novel single universal primer multiplex ligation-dependent probe amplification (SUP-MLPA) technique that uses only one universal primer to perform multiplex polymerase chain reaction (PCR) was developed. Two reversely complementary common sequences were designed on the 5' or 3' end of the ligation probes (LPs), which allowed the ligation products to be amplified through only a single universal primer (SUP). SUP-MLPA products were analyzed on sequencing gel electrophoresis with extraordinary resolution. This method avoided the high expenses associated with capillary electrophoresis, which was the commonly used detection instrument. In comparison with conventional multiplex PCR, which suffers from low sensitivity, nonspecificity, and amplification disparity, SUP-MLPA had higher specificity and sensitivity and a low detection limit of 0.1 ng for detecting single crop species when screening the presence of genetically modified crops. We also studied the effect of different lengths of stuffer sequences on the probes for the first time. Through comparing the results of quantitative PCR, the LPs with different stuffer sequences did not affect the ligation efficiency, which further increased the multiplicity of this assay. The improved SUP-MLPA and sequencing gel electrophoresis method will be useful for food and animal feed identification, bacterial detection, and verification of genetic modification status of crops.

  11. Emergency Portacaval Shunt Versus Rescue Portacaval Shunt in a Randomized Controlled Trial of Emergency Treatment of Acutely Bleeding Esophageal Varices in Cirrhosis—Part 3

    PubMed Central

    Isenberg, Jon I.; Wheeler, Henry O.; Haynes, Kevin S.; Jinich-Brook, Horacio; Rapier, Roderick; Vaida, Florin; Hye, Robert J.

    2010-01-01

    Background Emergency treatment of bleeding esophageal varices in cirrhosis is of singular importance because of the high mortality rate. Emergency portacaval shunt is rarely used today because of the belief, unsubstantiated by long-term randomized trials, that it causes frequent portal-systemic encephalopathy and liver failure. Consequently, portacaval shunt has been relegated solely to salvage therapy when endoscopic and pharmacologic therapies have failed. Question: Is the regimen of endoscopic sclerotherapy with rescue portacaval shunt for failure to control bleeding varices superior to emergency portacaval shunt? A unique opportunity to answer this question was provided by a randomized controlled trial of endoscopic sclerotherapy versus emergency portacaval shunt conducted from 1988 to 2005. Methods Unselected consecutive cirrhotic patients with acute bleeding esophageal varices were randomized to endoscopic sclerotherapy (n = 106) or emergency portacaval shunt (n = 105). Diagnostic workup was completed and treatment was initiated within 8 h. Failure of endoscopic sclerotherapy was defined by strict criteria and treated by rescue portacaval shunt (n = 50) whenever possible. Ninety-six percent of patients had more than 10 years of follow-up or until death. Results Comparison of emergency portacaval shunt and endoscopic sclerotherapy followed by rescue portacaval shunt showed the following differences in measurements of outcomes: (1) survival after 5 years (72% versus 22%), 10 years (46% versus 16%), and 15 years (46% versus 0%); (2) median post-shunt survival (6.18 versus 1.99 years); (3) mean requirements of packed red blood cell units (17.85 versus 27.80); (4) incidence of recurrent portal-systemic encephalopathy (15% versus 43%); (5) 5-year change in Child’s class showing improvement (59% versus 19%) or worsening (8% versus 44%); (6) mean quality of life points in which lower is better (13.89 versus 27.89); and (7) mean cost of care per

  12. Engineering cytochrome c peroxidase into cytochrome P450: a proximal effect on heme-thiolate ligation.

    PubMed

    Sigman, J A; Pond, A E; Dawson, J H; Lu, Y

    1999-08-24

    In an effort to investigate factors required to stabilize heme-thiolate ligation, key structural components necessary to convert cytochrome c peroxidase (CcP) into a thiolate-ligated cytochrome P450-like enzyme have been evaluated and the H175C/D235L CcP double mutant has been engineered. The UV-visible absorption, magnetic circular dichroism (MCD) and electron paramagnetic resonance (EPR) spectra for the double mutant at pH 8.0 are reported herein. The close similarity between the spectra of ferric substrate-bound cytochrome P450cam and those of the exogenous ligand-free ferric state of the double mutant with all three techniques support the conclusion that the latter has a pentacoordinate, high-spin heme with thiolate ligation. Previous efforts to prepare a thiolate-ligated mutant of CcP with the H175C single mutant led to Cys oxidation to cysteic acid [Choudhury et al. (1994) J. Biol. Chem. 267, 25656-25659]. Therefore it is concluded that changing the proximal Asp235 residue to Leu is critical in forming a stable heme-thiolate ligation in the resting state of the enzyme. To further probe the versatility of the CcP double mutant as a ferric P450 model, hexacoordinate low-spin complexes have also been prepared. Addition of the neutral ligand imidazole or of the anionic ligand cyanide results in formation of hexacoordinate adducts that retain thiolate ligation as determined by spectral comparison to the analogous derivatives of ferric P450cam. The stability of these complexes and their similarity to the analogous forms of P450cam illustrates the potential of the H175C/D235L CcP double mutant as a model for ferric P450 enzymes. This study marks the first time a stable cyanoferric complex of a model P450 has been made and demonstrates the importance of the environment around the primary coordination ligands in stabilizing metal-ligand ligation. PMID:10460168

  13. Prevalence and type of pain during conventional and self-ligating orthodontic treatment.

    PubMed

    Tecco, Simona; D'Attilio, Michele; Tetè, Stefano; Festa, Felice

    2009-08-01

    This study investigated the prevalence and type of pain experienced during orthodontic treatment in 30 subjects (12 males, 18 females, aged 12-18 years) with crowding. Fifteen patients were treated with conventional brackets (Victory Series) and 15 with self-ligating brackets (Damon SL II). The first archwire for all patients was a 0.014 inch nickel-titanium (NiTi) archwire with a force of approximately 100 g. Conventional brackets were ligated with elastomeric modules. A visual analogue scale (VAS) was used daily to assess the intensity of pain; the use of pain medication was also reported in a specially designed daybook for a total period of 3 months. Pearson's chi-square was used to investigate the difference between groups in the frequency of pain experience, its nature, and the use of analgesia. Non-parametric statistics (Mann-Whitney U-test) were computed to compare pain intensity between the groups. To investigate reported pain assessments, Friedman's two-way analysis of variance was used and the differences were estimated using Wilcoxon's signed-rank test. The results showed that pain was reported for a period of 9 days after archwire insertion. Patients treated with self-ligating brackets reported the highest pain intensity on the day following placement of the first archwire (VAS mean = 42.6), while those treated with conventional brackets experienced the greatest pain intensity at placement of the first archwire (VAS mean = 52) and after the second orthodontic appointment (VAS mean = 59.6). Analgesics were used by 16.5 per cent of patients treated with self-ligating brackets and by 10 per cent of those treated with conventional brackets, most often during the first 2 days after archwire placement. Patients treated with conventional brackets reported significantly more 'constant' pain than those treated with self-ligating brackets who complained of 'chewing/biting' pain. Pain appears to be common during orthodontic treatment but perhaps less intense when

  14. LIVER TRANSPLANTATION IN A RANDOMIZED CONTROLLED TRIAL OF EMERGENCY TREATMENT OF ACUTELY BLEEDING ESOPHAGEAL VARICES IN CIRRHOSIS

    PubMed Central

    Orloff, Marshall J.; Isenberg, Jon I.; Wheeler, Henry O.; Haynes, Kevin S.; Jinich-Brook, Horacio; Rapier, Roderick; Vaida, Florin; Hye, Robert J.; Orloff, Susan L.

    2010-01-01

    Background Bleeding esophageal varices (BEV) in cirrhosis has been considered an indication for liver transplantation (LT). This issue was examined in a randomized controlled trial (RCT) of unselected, consecutive patients with advanced cirrhosis and BEV that compared endoscopic sclerotherapy (EST) (n=106) to emergency direct portacaval shunt (EPCS) (n=105). Methods Diagnostic workup and treatment were initiated within 8 hours. Patients were evaluated for LT on admission and repeatedly thereafter. 96% underwent over 10 years of regular follow-up. The analysis was supplemented by 1300 unrandomized cirrhotic patients who previously underwent portacaval shunt (PCS) with 100% follow-up. Results In the RCT, long-term bleeding control was 100% following EPCS, only 20% following EST. 3, 5, 10, and 15-year survival rates were 75%, 73%, 46%, and 46% following EPCS, compared to 44%, 21%, 9%, and 9% following EST (p<0.001). Only 13 RCT patients (6%) were ultimately referred for LT mainly because of progressive liver failure; only 7 (3%) were approved for LT and only 4 (2%) underwent LT. 1- and 5-year LT survival rates were 0.68% and 0, compared to 81% and 73% after EPCS. In the 1300 unrandomized PCS patients. 50 (3.8%) were referred and 19 (1.5%) underwent LT. Five-year survival rate was 53% compared to 72% for all 1300 patients. Conclusions If bleeding is permanently controlled, as occurred invariably following EPCS, cirrhotic patients with BEV seldom require LT. PCS is effective first-line and long-term treatment. Should LT be required in patients with PCS, although technically more demanding, numerous studies have shown that PCS does not increase mortality or complications. EST is not effective emergency or long-term therapy. PMID:21168637

  15. Using Ultrasonic Transient Elastometry (FibroScan) to Predict Esophageal Varices in Patients with Viral Liver Cirrhosis.

    PubMed

    Hu, Zhongwei; Li, Yuyuan; Li, Chuo; Huang, Chunming; Ou, Zhitao; Guo, Jiawei; Luo, Hongbin; Tang, Xiaoping

    2015-06-01

    The correlation between liver stiffness (LS), measured by ultrasonic transient elastometry (FibroScan), and the presence and severity of esophageal varices (EV) in patients with viral cirrhosis of the liver has not been well documented to date. The study described here investigated the value of using FibroScan to predict EV. Patients with cirrhosis (200 patients: 167 cases caused by hepatitis B virus and 33 cases caused by hepatitis C virus) underwent both upper gastrointestinal endoscopy and FibroScan. Demographic, clinical, biochemical and endoscopic data and FibroScan-obtained LS parameters were collected. The mean LS value in patients with EV (33.2 kPa) was significantly higher than the mean LS value in patients without EV (18.6 kPa) (p < 0.05). The mean LS value in patients with grade 2 and 3 EV (38.3 kPa) was significantly higher than that in patients with grade 1 EV (24.8 kPa) (p < 0.05). Overall, FibroScan was 86.4% sensitive and 72.2% specific in predicting the presence of EV, with an area under the receiver operating characteristic curve (AUROC) of 0.84. The sensitivity and specificity for the patients with grade 2 or 3 EV were 84% and 73% (AUROC = 0.86). When FibroScan was combined with platelet count, the overall sensitivity and specificity of prediction increased to 84% and 80% (AUROC = 0.88), respectively, and 84% and 75% (AUROC = 0.89), respectively, in patients with grade 2 and 3 EV. FibroScan alone or combined with platelet count might predict the presence and severity of EV in patients with hepatitis B or C-related viral cirrhosis.

  16. Tubal ligation and ovarian cancer risk in a large cohort: Substantial variation by histological type.

    PubMed

    Gaitskell, Kezia; Green, Jane; Pirie, Kirstin; Reeves, Gillian; Beral, Valerie

    2016-03-01

    Histopathological and molecular studies suggest that different histological subtypes (histotypes) of ovarian cancer have different aetiologies. Few studies have been large enough to explore reliably the effect of tubal ligation (sterilization), which has been associated with a reduced overall risk of ovarian cancer, on different tumour histotypes. In a prospective study of 1.1 million UK women without prior cancer or bilateral oophorectomy, 8,035 ovarian cancers occurred during mean follow-up of 13.8 years. Using a Cox proportional hazards model, we estimated adjusted relative risks of ovarian cancer associated with tubal ligation. Overall, there was substantial heterogeneity in tumour risk associated with tubal ligation for the four main histotypes, serous, endometrioid, mucinous and clear cell (heterogeneity: p < 0.0001). For serous tumours, the most common histotype (n = 3,515), risks differed significantly between high-grade (RR: 0.77, 95% CI: 0.67-0.89) and low-grade tumours (RR: 1.13, 95% CI: 0.89-1.42); heterogeneity: p = 0.007. Relative risks were almost halved for endometrioid (n = 690, RR: 0.54, 95% CI: 0.43-0.69) and clear cell tumours (n = 401, RR: 0.55, 95% CI: 0.39-0.77), but there was no association between tubal ligation and mucinous tumours (n = 836, RR: 0.99, 95% CI: 0.84-1.18). For the main tumour histotypes we found little variation of risk by timing of tubal ligation. The significant differences by tumour histotype are unlikely to be due to confounding and are consistent with hypotheses that high-grade and low-grade serous tumours have different origins, and that some endometrioid and clear cell tumours might arise from cells and/or carcinogens travelling through the fallopian tubes.

  17. A study of the frictional characteristics of four commercially available self-ligating bracket systems.

    PubMed

    Budd, Steven; Daskalogiannakis, John; Tompson, Bryan D

    2008-12-01

    The objective of this investigation was to assess and compare the in vitro tribological behaviour of four commercially available self-ligating bracket systems. The frictional characteristics of the Damon3, Speed, In-Ovation R, and Time2 bracket systems were studied using a jig that mimics the three-dimensional movements that occur during sliding mechanics. Each bracket system was tested on the following stainless steel archwires: 0.016 x 0.022, 0.019 x 0.025, 0.020 round, and 0.021 x 0.021 inch Speed D-wire. An Instron testing machine with a 50 N load cell was used to measure the frictional resistance for each bracket/tooth assembly. The crosshead speed was set at a constant rate of 1 mm/minute, and each typodont tooth was moved along a fixed wire segment for a distance of 8 mm. Descriptive statistical analysis for each bracket/archwire combination with regard to frictional resistance was performed with a two-way, balanced analysis of variance for bracket type and wire size. The Damon3 bracket consistently demonstrated the lowest frictional resistance to sliding, while the Speed bracket produced significantly (P < 0.001) more frictional resistance than the other brackets tested for any given archwire. The self-ligation design (passive versus active) appears to be the primary variable responsible for the frictional resistance generated by self-ligating brackets during translation. Passively ligated brackets produce less frictional resistance; however, this decreased friction may result in decreased control compared with actively ligated systems. PMID:18974067

  18. Ligation bias in illumina next-generation DNA libraries: implications for sequencing ancient genomes.

    PubMed

    Seguin-Orlando, Andaine; Schubert, Mikkel; Clary, Joel; Stagegaard, Julia; Alberdi, Maria T; Prado, José Luis; Prieto, Alfredo; Willerslev, Eske; Orlando, Ludovic

    2013-01-01

    Ancient DNA extracts consist of a mixture of endogenous molecules and contaminant DNA templates, often originating from environmental microbes. These two populations of templates exhibit different chemical characteristics, with the former showing depurination and cytosine deamination by-products, resulting from post-mortem DNA damage. Such chemical modifications can interfere with the molecular tools used for building second-generation DNA libraries, and limit our ability to fully characterize the true complexity of ancient DNA extracts. In this study, we first use fresh DNA extracts to demonstrate that library preparation based on adapter ligation at AT-overhangs are biased against DNA templates starting with thymine residues, contrarily to blunt-end adapter ligation. We observe the same bias on fresh DNA extracts sheared on Bioruptor, Covaris and nebulizers. This contradicts previous reports suggesting that this bias could originate from the methods used for shearing DNA. This also suggests that AT-overhang adapter ligation efficiency is affected in a sequence-dependent manner and results in an uneven representation of different genomic contexts. We then show how this bias could affect the base composition of ancient DNA libraries prepared following AT-overhang ligation, mainly by limiting the ability to ligate DNA templates starting with thymines and therefore deaminated cytosines. This results in particular nucleotide misincorporation damage patterns, deviating from the signature generally expected for authenticating ancient sequence data. Consequently, we show that models adequate for estimating post-mortem DNA damage levels must be robust to the molecular tools used for building ancient DNA libraries.

  19. Ligation Bias in Illumina Next-Generation DNA Libraries: Implications for Sequencing Ancient Genomes

    PubMed Central

    Seguin-Orlando, Andaine; Schubert, Mikkel; Clary, Joel; Stagegaard, Julia; Alberdi, Maria T.; Prado, José Luis; Prieto, Alfredo; Willerslev, Eske; Orlando, Ludovic

    2013-01-01

    Ancient DNA extracts consist of a mixture of endogenous molecules and contaminant DNA templates, often originating from environmental microbes. These two populations of templates exhibit different chemical characteristics, with the former showing depurination and cytosine deamination by-products, resulting from post-mortem DNA damage. Such chemical modifications can interfere with the molecular tools used for building second-generation DNA libraries, and limit our ability to fully characterize the true complexity of ancient DNA extracts. In this study, we first use fresh DNA extracts to demonstrate that library preparation based on adapter ligation at AT-overhangs are biased against DNA templates starting with thymine residues, contrarily to blunt-end adapter ligation. We observe the same bias on fresh DNA extracts sheared on Bioruptor, Covaris and nebulizers. This contradicts previous reports suggesting that this bias could originate from the methods used for shearing DNA. This also suggests that AT-overhang adapter ligation efficiency is affected in a sequence-dependent manner and results in an uneven representation of different genomic contexts. We then show how this bias could affect the base composition of ancient DNA libraries prepared following AT-overhang ligation, mainly by limiting the ability to ligate DNA templates starting with thymines and therefore deaminated cytosines. This results in particular nucleotide misincorporation damage patterns, deviating from the signature generally expected for authenticating ancient sequence data. Consequently, we show that models adequate for estimating post-mortem DNA damage levels must be robust to the molecular tools used for building ancient DNA libraries. PMID:24205269

  20. Tubal ligation and ovarian cancer risk in a large cohort: Substantial variation by histological type

    PubMed Central

    Green, Jane; Pirie, Kirstin; Reeves, Gillian

    2015-01-01

    Histopathological and molecular studies suggest that different histological subtypes (histotypes) of ovarian cancer have different aetiologies. Few studies have been large enough to explore reliably the effect of tubal ligation (sterilization), which has been associated with a reduced overall risk of ovarian cancer, on different tumour histotypes. In a prospective study of 1.1 million UK women without prior cancer or bilateral oophorectomy, 8,035 ovarian cancers occurred during mean follow‐up of 13.8 years. Using a Cox proportional hazards model, we estimated adjusted relative risks of ovarian cancer associated with tubal ligation. Overall, there was substantial heterogeneity in tumour risk associated with tubal ligation for the four main histotypes, serous, endometrioid, mucinous and clear cell (heterogeneity: p < 0.0001). For serous tumours, the most common histotype (n = 3,515), risks differed significantly between high‐grade (RR: 0.77, 95% CI: 0.67–0.89) and low‐grade tumours (RR: 1.13, 95% CI: 0.89–1.42); heterogeneity: p = 0.007. Relative risks were almost halved for endometrioid (n = 690, RR: 0.54, 95% CI: 0.43–0.69) and clear cell tumours (n = 401, RR: 0.55, 95% CI: 0.39–0.77), but there was no association between tubal ligation and mucinous tumours (n = 836, RR: 0.99, 95% CI: 0.84–1.18). For the main tumour histotypes we found little variation of risk by timing of tubal ligation. The significant differences by tumour histotype are unlikely to be due to confounding and are consistent with hypotheses that high‐grade and low‐grade serous tumours have different origins, and that some endometrioid and clear cell tumours might arise from cells and/or carcinogens travelling through the fallopian tubes. PMID:26378908

  1. Tubal ligation, hysterectomy, and epithelial ovarian cancer in the New England Case-Control Study

    PubMed Central

    Rice, Megan S.; Murphy, Megan A.; Vitonis, Allison F.; Cramer, Daniel W.; Titus, Linda J.; Tworoger, Shelley S.; Terry, Kathryn L.

    2013-01-01

    Previous studies have observed that tubal ligation and hysterectomy are associated with a decreased risk of ovarian cancer; however little is known about whether these associations vary bysurgical characteristics, individual characteristics, or tumor histology. We used logistic regression to examine tubal ligation, simple hysterectomy, and hysterectomy with unilateral oophorectomy in relation to risk of epithelial ovarian cancer in the New England Case-Control study. Our primary analysis included 2,265 cases and 2,333 controls. Overall, tubal ligation was associated with a lower risk of epithelial ovarian cancer (OR: 0.82, 95%CI: 0.68-0.97), especially for endometrioid tumors (OR=0.45, 95%CI: 0.29-0.69). The inverse association between tubal ligation and ovarian cancer risk was stronger for women who had undergone the procedure at the time of last delivery (OR=0.60, 95%CI: 0.42-0.84) rather than at a later time (OR=0.93, 95%CI: 0.75-1.15). Overall, simple hysterectomy was not associated with ovarian cancer risk (OR: 1.09, 95%CI: 0.83, 1.42), although it was associated with a non-significant decreased risk of ovarian cancer among women who underwent the procedure at age 45 or older (RR: 0.64, 95%CI: 0.40, 1.02) or within the last 10 years (OR=0.65, 95%CI: 0.38, 1.13). Overall, women who had a hysterectomy with a unilateral oophorectomy had significantly lower risk of ovarian cancer (OR=0.65, 95%CI: 0.45-0.94). In summary, tubal ligation and hysterectomy with unilateral oophorectomy were inversely associated with ovarian cancer risk in a large population-based case-control study. Additional research is necessary to understand the potential biologic mechanisms by which these procedures may reduce ovarian cancer risk. PMID:23650079

  2. High Ligation of Inferior Mesenteric Artery in Left Colonic and Rectal Cancers: Lymph Node Yield and Survival Benefit.

    PubMed

    Charan, Ishwar; Kapoor, Akhil; Singhal, Mukesh Kumar; Jagawat, Namrata; Bhavsar, Deepak; Jain, Vikas; Kumar, Vanita; Kumar, Harvindra Singh

    2015-12-01

    During surgery for colorectal cancer, the inferior mesenteric artery (IMA) may be ligated either directly at the origin of the IMA from the aorta (high ligation) or at a point just below the origin of the left colic artery (low ligation). Sixty patients of left colonic and rectal cancer undergoing elective curative surgery in 2007 and 2008 were selected for this observational study. The resected lymph nodes were grouped into three levels: along the bowel wall (D1), along IMA below left colic (D2), and along the IMA and its root (D3). Statistical analysis was performed with SPSS version 20.0. D2 level was involved pathologically in 20 (33.3 %) and D3 in six out of 44 (13.6 %) patients. The median nodal yield with high and low ligation were 33 and 25, respectively (p = 0.048). Median overall survival for high ligation was 62 months versus 42 months for low ligation (p = 0.190). High ligation of the IMA for rectal and left colonic cancers can improve lymph node yield, thus facilitating accurate tumor staging and thus better disease prognostication, but the survival benefit is not significant. PMID:27011519

  3. High Ligation of Inferior Mesenteric Artery in Left Colonic and Rectal Cancers: Lymph Node Yield and Survival Benefit.

    PubMed

    Charan, Ishwar; Kapoor, Akhil; Singhal, Mukesh Kumar; Jagawat, Namrata; Bhavsar, Deepak; Jain, Vikas; Kumar, Vanita; Kumar, Harvindra Singh

    2015-12-01

    During surgery for colorectal cancer, the inferior mesenteric artery (IMA) may be ligated either directly at the origin of the IMA from the aorta (high ligation) or at a point just below the origin of the left colic artery (low ligation). Sixty patients of left colonic and rectal cancer undergoing elective curative surgery in 2007 and 2008 were selected for this observational study. The resected lymph nodes were grouped into three levels: along the bowel wall (D1), along IMA below left colic (D2), and along the IMA and its root (D3). Statistical analysis was performed with SPSS version 20.0. D2 level was involved pathologically in 20 (33.3 %) and D3 in six out of 44 (13.6 %) patients. The median nodal yield with high and low ligation were 33 and 25, respectively (p = 0.048). Median overall survival for high ligation was 62 months versus 42 months for low ligation (p = 0.190). High ligation of the IMA for rectal and left colonic cancers can improve lymph node yield, thus facilitating accurate tumor staging and thus better disease prognostication, but the survival benefit is not significant.

  4. Associated Liver Partition and Portal Vein Ligation (ALPPS) vs Selective Portal Vein Ligation (PVL) for Staged Hepatectomy in a Rat Model. Similar Regenerative Response?

    PubMed

    García-Pérez, Rocío; Revilla-Nuin, Beatriz; Martínez, Carlos M; Bernabé-García, Angel; Baroja Mazo, Alberto; Parrilla Paricio, Pascual

    2015-01-01

    Associated liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a two-stage hepatectomy technique which can be associated with a hypertrophic stimulus on the future liver remnant (FLR) stronger than other techniques--such as portal vein ligation (PVL). However, the reason of such hypertrophy is still unclear, but it is suggested that liver transection combined with portal vein ligation (ALPPS) during the first stage of this technique may play a key role. The aim of this study is to compare the hypertrophic stimulus on the FLR and the clinical changes associated with both ALPPS and PVL in a rat surgical model. For this purpose, three groups of SD rats were used, namely ALPPS (n = 30), PVL (n = 30) and sham-treated (n = 30). The second stage of ALPPS (hepatectomy of the atrophic lobes), was performed at day 8. Blood and FLR samples were collected at 1, 24, 48 hours, 8 days and 12 weeks after the surgeries. ALPPS provoked a greater degree of hypertrophy of the FLR than the PVL at 48 hours and 8 days (p<0.05). The molecular pattern was also different, with the highest expression of IL-1β at 24h, IL-6 at 8 days, and HGF and TNF-α at 48 hours and 8 days (p<0.05). ALPPS also brought about a mild proliferative stimulus at 12 weeks, with a higher expression of HGF and TGF-β (p<0.05) than PVL. Clinically, ALPPS caused a significant liver damage during the first 48 hours, with a recovery of liver function at day 8. In conclusion, ALPPS seems to induce higher functional hypertrophy on the FLR than PVL at day 8. Such regenerative response seems to be leaded by a complex interaction between pro-mitogenic (IL-6, HGF, TNF-α) and antiproliferative (IL1-β and TGF-β) cytokines.

  5. Une complication rare des léiomyomes utérins: hémopéritoine massif par rupture de varices

    PubMed Central

    Ymele, Florent Fouelifack; Tsuala, Jovanny Fouogue; Fouedjio, Jeanne Hortence; Nangué, Charlette; De Kayo, Caroline Kayo; Dobgima, Pisoh Walter; Mbu, Robinson Enoh

    2013-01-01

    Les léiomyomes utérins sont des causes exceptionnelles d'hémopéritoine. Nous rapportons ici le cas d'une femme de 46 ans nullipare, en instance d'une hystérectomie totale indiquée pour utérus polymyomateux symptomatique. Elle a été opérée en urgence pour hémopéritoine aigu et massif compliqué de choc hémorragique. L'origine de l'hémopéritoine était la rupture spontanée d'une varice du léiomyome. Quoique rare l'éventualité d'un hémopéritoine causé par un fibrome utérin devrait être évoquée devant tout abdomen aigu spontané chez une femme en âge de procréer. La présence de varices sur les fibromes augmenterait le risque d'hémorragie spontanée. PMID:23717724

  6. Experience with pyeloureterostomy associated with simple ligation of native ureter without ipsilateral nephrectomy in renal transplantation.

    PubMed

    Baquero, A; Ginsberg, P C; Kaschak, D; Raja, R; Schneeberg, A; Solish, L; Bannett, A D

    1985-03-01

    Ureteroneocystostomy was used as the primary method of urinary tract reconstruction in 282 allograft renal transplants at our center since 1965. A nonrefluxing anastomosis was incorporated whenever possible. Seven patients who suffered major urological complications involving the ureteroneocystostomy required pyeloureterostomy as the method of repair using the patient's distal native ureter. No ipsilateral nephrectomy was performed and simple ligation of the native ureter with nonabsorbable suture was accomplished. Of the 7 patients 3 suffered hydronephrosis of the native kidney. None of these patients had signs or symptoms secondary to acute and chronic ureteral occlusion. Our experience suggests that intentional ligation of the native ureter during pyeloureterostomy does not result in increased morbidity to the transplant patient, and that the need for ipsilateral nephrectomy with its own added morbidity may not be necessary.

  7. Enzyme-free amplified detection of DNA by an autonomous ligation DNAzyme machinery.

    PubMed

    Wang, Fuan; Elbaz, Johann; Willner, Itamar

    2012-03-28

    The Zn(2+)-dependent ligation DNAzyme is implemented as a biocatalyst for the amplified detection of a target DNA by the autonomous replication of a nucleic acid reporter unit that is generated by the catalyzed ligation process. The reporter units enhance the formation of active DNAzyme units, thus leading to the isothermal autocatalytic formation of the reporter elements. The system was further developed and applied for the amplified detection of Tay-Sachs genetic disorder mutant, with a detection limit of 1.0 × 10(-11) M. Besides providing a versatile paradigm for the amplified detection of DNA, the system reveals a new, enzyme-free, isothermal, autocatalytic mechanism that introduces means for effective programmed synthesis. PMID:22404383

  8. [Infra-fascial ligation of incompetent perforating veins for cure of varicose ulcer (author's transl)].

    PubMed

    Schoevaerdts, J C

    1975-11-01

    This is a series of 141 varicoses ulcers operated within 3 years (1971 to 1974), all with infra-fascial ligation of incompetent perforating veins (technique of Cockett-Linton). The author describes 3 combined methods used to obtain the most precise diagnosis of the venous insufficiency: A. Careful physical examination for axial or perforating imcompetence. B. Systematic phlebography for search of deep networks, of perforating veins and discovery of particular superficial venous networks. C. Ultrasonic Doppler technique for search of incompetent perforating veins. Surgical cure is described, based on this precise diagnosis, aiming at ligation of axial and of perforating veins under the fascia, level with the deep network. The results are encouraging as there were only 3 recurrences within 3 years after the 141 operations. These were reoperated after phlebographic control.

  9. [An evaluation of the long-term results of palatopharyngeal closure function after velopharyngeal ring ligation].

    PubMed

    Zhang, S; Wei, F; Zhang, P

    1997-08-01

    16 cases were selected randomly from a group of 36 postoperative patients who underwent velopharyngeal ring ligation 16 years ago for evaluation of pronunciation, pharyngeal radiography, and electric endostroboskop to evaluate the patients' velopharygeal closure function. It was found that the pronunciation function of 93% patients were in good status. The results showed that centripetal force of velopharyngeal ring ligation made the velopharyngeal cavity reduced from the right to left and from anterior to posterior sides. It was good for sphincter of velopharyngeal moving, which could reduce the space of pharyngeal cavity and add the length of soft palate. The velopharyngeal closure was improved, which produced a good condition for the recovery of pronunciation function, at the same time, the change of pharyngeal cavity adapts to the patient's growth without limiting the growth and development of nasovelopharyngeal. PMID:11480008

  10. Atrophy of submandibular gland by the duct ligation and a blockade of SP receptor in rats

    PubMed Central

    Hishida, Sumiyo; Ozaki, Noriyuki; Honda, Takashi; Shigetomi, Toshio; Ueda, Minoru; Hibi, Hideharu; Sugiura, Yasuo

    2016-01-01

    ABSTRACT To clarify the mechanisms underlying the submandibular gland atrophies associated with ptyalolithiasis, morphological changes were examined in the rat submandibular gland following either surgical intervention of the duct or functional blockade at substance P receptors (SPRs). Progressive acinar atrophy was observed after duct ligation or avulsion of periductal tissues. This suggested that damage to periductal tissue involving nerve fibers might contribute to ligation-associated acinar atrophy. Immunohistochemically labeled-substance P positive nerve fibers (SPFs) coursed in parallel with the main duct and were distributed around the interlobular, striated, granular and intercalated duct, and glandular acini. Strong SPR immunoreactivity was observed in the duct. Injection into the submandibular gland of a SPR antagonist induced marked acinar atrophy. The results revealed that disturbance of SPFs and SPRs might be involved in the atrophy of the submandibular gland associated with ptyalolithiasis. PMID:27303108

  11. An unusual complication of epistaxis: cerebral abscess formation after anterior ethmoidal artery ligation.

    PubMed

    Murer, Karin; Holzmann, David; Burkhardt, Jan-Karl; Soyka, Michael Benjamin

    2015-12-29

    Epistaxis is a very common emergency in otorhinolaryngology. Anterior ethmoidal artery ligation using an external approach is one of the surgical options in posterior epistaxis. We present, to the best of our knowledge, the first reported case of an intracerebral abscess after epistaxis treatment with ligation of the anterior ethmoidal artery using an endoscopic-assisted external approach in a 56-year-old patient. The patient presented 4 days postoperatively with an orbital cellulitis. A CT was performed and a frontobasal hypodensity was found. An additional MR tomography the next day showed a lesion suspicious for an intracerebral abscess. Despite intravenous antibiotic therapy, the lesion increased and was successfully treated by the neurosurgeons, with abscess resection over a craniotomy and frontobasal repair using a pedicled periosteal flap. Surgeons have to be aware of this rare but possibly lethal severe complication and should consider early imaging studies, especially if a periorbital cellulitis appears.

  12. THE EFFECT OF BILE DUCT LIGATION AND BILE DIVERSION ON FK506 PHARMACOKINETICS IN DOGS1

    PubMed Central

    Furukawa, Hiroyoki; Imventarza, Oscar; Venkataramanan, Raman; Suzuki, Masatoshi; Zhu, Yue; Warty, Vijay S.; Fung, John; Todo, Satoru; Starzl, Thomas E.

    2011-01-01

    Mongrel or beagle dogs were submitted to bile duct ligation, or to extraenteric biliary diversion by means of choledochoureterostomy. The kinetics of intravenously administered FK506 was not changed from control status two weeks after bile duct ligation, but the bioavailability of orally administered FK506 was nearly quadrupled. Following oral administration, the absorption of FK508 was highly variable. The results indicate that in dogs FK506 is absorbed from the intestine just as efficiently in the absence of enteric bile and in presence of exogenous bile salt supplement when compared with its absorption in presence of normal bile drainage. These findings with FK506 are different from those with cyclosporine after biliary obstruction or diversion and will have important practical as well as experimental ramifications. PMID:1373531

  13. A novel sensitive and selective ligation-based ATP assay using a molecular beacon.

    PubMed

    Ma, Changbei; Tang, Zhiwen; Wang, Kemin; Yang, Xiaohai; Tan, Weihong

    2013-05-21

    In this paper, a novel, facile fluorometric ATP assay with high sensitivity and excellent selectivity has been reported. This approach utilizes a molecular beacon, T4 DNA ligase and two short oligonucleotides. In the presence of ATP, the T4 DNA ligase catalyzes the ligation reaction and the ligation product restores the fluorescence of the molecular beacon. Owing to the high sensitivity of the molecular beacon and T4 DNA ligase's high substrate dependence, this novel ATP assay demonstrates exceptional selectivity and high sensitivity down to 0.14 nM in homogeneous solution. Cellular ATP concentrations in several cell lines have been determined by measuring the lysate sample containing 8.0 × 10(3) cells.

  14. Identification of cytotoxic agents disrupting synovial sarcoma oncoprotein interactions by proximity ligation assay

    PubMed Central

    Laporte, Aimée N.; Ji, Jennifer X.; Ma, Limin; Nielsen, Torsten O.; Brodin, Bertha A.

    2016-01-01

    Conventional cytotoxic therapies for synovial sarcoma provide limited benefit. Drugs specifically targeting the product of its driver translocation are currently unavailable, in part because the SS18-SSX oncoprotein functions via aberrant interactions within multiprotein complexes. Proximity ligation assay is a recently-developed method that assesses protein-protein interactions in situ. Here we report use of the proximity ligation assay to confirm the oncogenic association of SS18-SSX with its co-factor TLE1 in multiple human synovial sarcoma cell lines and in surgically-excised human tumor tissue. SS18-SSX/TLE1 interactions are disrupted by class I HDAC inhibitors and novel small molecule inhibitors. This assay can be applied in a high-throughput format for drug discovery in fusion-oncoprotein associated cancers where key effector partners are known. PMID:27120803

  15. Alkyne Ligation Handles: Propargylation of Hydroxyl, Sulfhydryl, Amino, and Carboxyl Groups via the Nicholas Reaction.

    PubMed

    Wells, Sarah M; Widen, John C; Harki, Daniel A; Brummond, Kay M

    2016-09-16

    The Nicholas reaction has been applied to the installation of alkyne ligation handles. Acid-promoted propargylation of hydroxyl, sulfhydryl, amino, and carboxyl groups using dicobalt hexacarbonyl-stabilized propargylium ions is reported. This method is useful for introduction of propargyl groups into base-sensitive molecules, thereby expanding the toolbox of methods for the incorporation of alkynes for bio-orthogonal reactions. High-value molecules are used as the limiting reagent, and various propargylium ion precursors are compared. PMID:27570975

  16. Effects on Bacterial Translocation of High-Fat Enteral Nutrition in Bile Duct Ligated Rats

    PubMed Central

    Elipek, Tufan; Utkan, Nihat Zafer

    2012-01-01

    Objective: Bacterial Translocation (BT) from the gastrointestinal system is at the center of current sepsis theories. In patients with obstructive jaundice, the absence of intraluminal bile flow causes some alterations and mucosal damage in the gut. In the present study, it was aimed to investigate the effects on BT of high-fat enteral nutrition in bile duct ligated rats. Material and Methods: In this study, a total of 28 healthy Spraque-Dawley rats, weighing 230–300 gr, were grouped into four as sham group, control group, high-fat enteral nutrition group and low-fat enteral nutrition group. The rats in all the groups were sacrificed on the seventh postoperative day The values of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), total and direct bilirubin were measured for biochemical evaluation. Also, samples were taken from the blood, lung, liver, spleen and mesenteric lymph nodes for microbiological evaluation. The results were calculated as CFU/gr and evaluated statistically. Results: In all bile duct ligated rats, all findings of obstructive jaundice were observed clinically (in postoperatively third day) and in the laboratory. It was determined that the lymphatic system is an essential pathway for BT, as reported by similar studies. However, it was observed in this study that the high-fat enteral nutrition may be not severely effective in reducing BT in bile duct ligated rats. The results were supported by statistical analyses. Conclusion: It was observed that high-fat enteral nutrition has no meaningful effects on reducing BT in bile duct ligated rats. PMID:25207019

  17. Mandibular dental arch changes associated with treatment of crowding using self-ligating and conventional brackets.

    PubMed

    Pandis, Nicholas; Polychronopoulou, Argy; Makou, Margarita; Eliades, Theodore

    2010-06-01

    The purpose of this study was to investigate the effect of treatment of mandibular crowding with self-ligating and conventional brackets on dental arch variables. Fifty-six patients were selected from a pool of subjects satisfying the following inclusion criteria: non-extraction treatment in the mandibular or maxillary arches, eruption of all mandibular teeth, no spaces and an irregularity index greater than 2 mm in the mandibular arch, and no adjunct treatment such as etxra- or intraoral appliances. The patients were assigned to two groups: one group received treatment with the self-ligating bracket and the other with a conventional edgewise appliance, both with a 0.022 inch slot. Lateral cephalometric radiographs obtained at the beginning (T1) and end (T2) of treatment were used to assess the alteration in mandibular incisor inclination, and measurements of intercanine and intermolar widths were made on dental casts to investigate changes associated with the correction. The results were analysed with bivariate and multivariate linear regression analysis in order to examine the effect of the bracket systems on arch width or lower incisor inclination, adjusting for the confounding effect of demographic and clinical characteristics. An alignment-induced increase in the proclination of the mandibular incisors was observed for both groups; no difference was identified between self-ligating and conventional brackets with respect to this parameter. Likewise, an increase in intercanine and intermolar widths was noted for both bracket groups; the self-ligating group showed a higher intermolar width increase than the conventional group, whereas the amount of crowding and Angle classification were not significant predictors of post-treatment intermolar width. PMID:19959610

  18. Are self-ligating brackets related to less formation of Streptococcus mutans colonies? A systematic review

    PubMed Central

    do Nascimento, Leonard Euler Andrade Gomes; de Souza, Margareth Maria Gomes; Azevedo, Angela Rita Pontes; Maia, Lucianne Cople

    2014-01-01

    Objective To verify, by means of a systematic review, whether the design of brackets (conventional or self-ligating) influences adhesion and formation of Streptococcus mutans colonies. Methods Search strategy: four databases (Cochrane Central Register of Controlled Trials, Ovid ALL EMB Reviews, PubMed and BIREME) were selected to search relevant articles covering the period from January 1965 to December 2012. Selection Criteria: in first consensus by reading the title and abstract. The full text was obtained from publications that met the inclusion criteria. Data collection and analysis: Two reviewers independently extracted data using the keywords: conventional, self-ligating, biofilm, Streptococcus mutans, and systematic review; and independently evaluated the quality of the studies. In case of divergence, the technique of consensus was adopted. Results The search strategy resulted in 1,401 articles. The classification of scientific relevance revealed the high quality of the 6 eligible articles of which outcomes were not unanimous in reporting not only the influence of the design of the brackets (conventional or self-ligating) over adhesion and formation of colonies of Streptococcus mutans, but also that other factors such as the quality of the bracket type, the level of individual oral hygiene, bonding and age may have greater influence. Statistical analysis was not feasible because of the heterogeneous methodological design. Conclusions Within the limitations of this study, it was concluded that there is no evidence for a possible influence of the design of the brackets (conventional or self-ligating) over colony formation and adhesion of Streptococcus mutans. PMID:24713561

  19. Tubal Ligation in Catholic Hospitals: A Qualitative Study of Ob-Gyns’ Experiences

    PubMed Central

    Stulberg, Debra B.; Hoffman, Yael; Dahlquist, Irma Hasham; Freedman, Lori R.

    2014-01-01

    Objective Tubal sterilization remains one of the most commonly requested contraceptive methods in the United States. Catholic hospital policy prohibits all sterilizations, but this ban is not uniformly enforced. We conducted this study to assess obstetrician-gynecologists’ beliefs and experiences with tubal ligation in Catholic hospitals. Study Design We interviewed 31 obstetrician-gynecologists geographically dispersed throughout the U.S. who responded to a national survey and agreed to be contacted for a follow-up interview or who were referred by colleagues from the survey sample. Twenty-seven had experienced working in a Catholic hospital. Interviews were open-ended and guided by a semi-structured instrument. Transcripts were thematically analyzed. Results Obstetrician-gynecologists disagreed with strict prohibition of sterilizations, especially when denying a tubal ligation placed the patient at increased medical risk. Cesarean delivery in Catholic hospitals raised frustration for obstetrician-gynecologists when the hospital prohibited a simultaneous tubal ligation and, thus, sent the patient for an unnecessary subsequent surgery. Obstetrician-gynecologists described some hospitals allowing tubal ligations in limited circumstances, but these workarounds were vulnerable to changes in enforcement. Some obstetrician-gynecologists reported that Catholic policy posed greater barriers for low-income patients and those with insurance restrictions. Conclusion Obstetrician-gynecologists working in Catholic hospitals in this study did not share the Church’s beliefs on sterilization. Research to understand patients’ experiences and knowledge of their sterilization options is warranted in order to promote women’s autonomy and minimize risk of harm. Implications Statement Tubal sterilization, even when medically indicated or in conjunction with cesarean delivery, is severely restricted for women delivering in Catholic hospitals. For women whose only access to

  20. Total synthesis of daptomycin by cyclization via a chemoselective serine ligation.

    PubMed

    Lam, Hiu Yung; Zhang, Yinfeng; Liu, Han; Xu, Jianchao; Wong, Clarence T T; Xu, Ci; Li, Xuechen

    2013-04-24

    A total synthesis of daptomycin, the first natural product antibiotic launched in a generation, was achieved. This convergent synthesis relies on an efficient macrocyclization via a serine ligation to assemble the 31-membered cyclic depsipeptide. The difficult esterification by the nonproteinogenic amino acid kynurenine was accomplished via the esterification of a threonine residue by a suitably protected Trp ester, followed by ozonolysis. This synthesis provides a foundation and framework to prepare varied analogues of daptomycin to establish its structure-activity profile.

  1. EXPRESSED PROTEIN LIGATION. A NEW TOOL FOR THE BIOSYNTHESIS OF CYCLIC POLYPEPTIDES

    SciTech Connect

    Kimura, R; Camarero, J A

    2004-11-11

    The present paper reviews the use of expressed protein ligation for the biosynthesis of backbone cyclic polypeptides. This general method allows the in vivo and in vitro biosynthesis of cyclic polypeptides using recombinant DNA expression techniques. Biosynthetic access to backbone cyclic peptides opens the possibility to generate cell-based combinatorial libraries that can be screened inside living cells for their ability to attenuate or inhibit cellular processes.

  2. Early Safety and Efficacy of Percutaneous Left Atrial Appendage Suture Ligation

    PubMed Central

    Price, Matthew J.; Gibson, Douglas N.; Yakubov, Steven J.; Schultz, Jason C.; Di Biase, Luigi; Natale, Andrea; Burkhardt, J. David; Pershad, Ashish; Byrne, Timothy J.; Gidney, Brett; Aragon, Joseph R.; Goldstein, Jeffrey; Moulton, Kriegh; Patel, Taral; Knight, Bradley; Lin, Albert C.; Valderrábano, Miguel

    2015-01-01

    BACKGROUND Transcatheter left atrial appendage (LAA) ligation may represent an alternative to oral anticoagulation for stroke prevention in atrial fibrillation.. OBJECTIVES This study sought to assess the early safety and efficacy of transcatheter ligation of the LAA for stroke prevention in atrial fibrillation.. METHODS This was a retrospective, multicenter study of consecutive patients undergoing LAA ligation with the Lariat device at 8 U.S. sites. The primary endpoint was procedural success, defined as device success (suture deployment and <5 mm leak by post-procedure transesophageal echocardiography), and no major complication at discharge (death, myocardial infarction, stroke, Bleeding Academic Research Consortium bleeding type 3 or greater, or cardiac surgery). Post-discharge management was per operator discretion. RESULTS A total of 154 patients were enrolled. Median CHADS2 score (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke, transient ischemic attack, or thromboembolism [doubled]) was 3 (interquartile range: 2 to 4). Device success was 94%, and procedural success was 86%. A major complication occurred in 15 patients (9.7%). There were 14 major bleeds (9.1%), driven by the need for transfusion (4.5%). Significant pericardial effusion occurred in 16 patients (10.4%). Follow-up was available in 134 patients at a median of 112 days (interquartile range: 50 to 270 days): Death, myocardial infarction, or stroke occurred in 4 patients (2.9%). Among 63 patients with acute closure and transesophageal echocardiography follow-up, there were 3 thrombi (4.8%) and 13 (20%) with residual leak. CONCLUSIONS In this initial multicenter experience of LAA ligation with the Lariat device, the rate of acute closure was high, but procedural success was limited by bleeding. A prospective randomized trial is required to adequately define clinical efficacy, optimal post-procedure medical therapy, and the effect of operator experience on

  3. Cardioprotective effect of polydatin on ventricular remodeling after myocardial infarction in coronary artery ligation rats.

    PubMed

    Gao, Yan; Gao, Jianping; Chen, Changxun; Wang, Huilin; Guo, Juan; Wu, Rong

    2015-05-01

    The purpose of this study was to explore the effect of polydatin on ventricular remodeling after myocardial infarction in coronary artery ligation rats and to elucidate the underlying mechanisms. A rat model of ventricular remodeling after myocardial infarction was established by left coronary artery ligation. Rats with coronary artery ligation were randomly divided into five groups: control, plus 40 mg/kg captopril, plus 25 mg/kg polydatin, plus 50 mg/kg polydatin, and plus 100 mg/kg polydatin. The sham-operated group was used as a negative control. Rats were administered intragastrically with the corresponding drugs or drinking water for seven weeks. At the end of the treatment, the left ventricular weight index and heart weight index were assessed. The cross-sectional size of cardiomyocytes was measured by staining myocardium tissue with hematoxylin and eosin. Collagen content was counted by Sirius red in aqueous saturated picric acid. The concentrations of angiotensin I, angiotensin II, aldosterone, and endothelin 1 in myocardium or serum were determined by radioimmunoassay. Hydroxyproline and nitric oxide concentrations and glutathione peroxidase and catalase activities in serum were measured by ultraviolet spectrophotometry. Our results showed that seven weeks of polydatin treatment resulted in a significantly reduced left ventricular weight index, heart weight index, serum concentrations of hydroxyproline and aldosterone, an increased concentration of nitric oxide as well as enhanced activities of glutathione peroxidase and catalase. Myocardial angiotensin I, angiotensin II, and endothelin 1 levels were also reduced. The cardiomyocyte cross-sectional area and collagen deposition diminished. This study suggests that polydatin may attenuate ventricular remodeling after myocardial infarction in coronary artery ligation rats through restricting the excessive activation of the renin-angiotensin-aldosterone system and inhibiting peroxidation.

  4. Tubal ligation, hysterectomy, unilateral oophorectomy, and risk of ovarian cancer in the Nurses’ Health Studies

    PubMed Central

    Rice, Megan S; Hankinson, Susan E; Tworoger, Shelley S

    2014-01-01

    Objective To prospectively examine if the association between tubal ligation, hysterectomy, unilateral oophorectomy, and ovarian cancer varied by patient, tumor, and surgical characteristics. Design Two prospective cohort studies (Nurses’ Health Study and NHSII). Setting Participants were identified from across the US and followed for up to 34 years. Patient(s) A cohort of 121,700 married US female nurses, aged 30 to 55 at baseline and another cohort of 116,430 US female nurses aged 25 to 42 at baseline. Intervention(s) We obtained data on gynecologic surgeries and ovarian cancer incidence through biennial questionnaires. We calculated hazard ratios and 95% confidence intervals adjusted for known and suspected ovarian cancer risk factors. Main Outcome Measure(s) Confirmed incident epithelial ovarian cancer. Results Overall, tubal ligation was associated with a decreased risk of ovarian cancer HR: 0.76, 95%CI: 0.64–0.90). The inverse association was stronger for non-serous tumors (HR: 0.57, 95%CI: 0.40–0.82) and among women younger than 35 at surgery HR: 0.67, 95%CI: 0.49–0.90). Hysterectomy was associated with a decreased risk of ovarian cancer (HR: 0.80, 95%CI: 0.66–0.97) and was somewhat stronger for non-serous tumors (HR: 0.70, 95%CI: 0.49–1.02). Unilateral oophorectomy was associated with a 30% lower risk (HR: 0.70, 95%CI: 0.53–0.91), which did not differ by histologic subtype. Conclusions Our study provides further support that tubal ligation reduces the risk of ovarian cancer, particularly for non-serous tumors and when conducted prior to age 35. The inverse association with hysterectomy along with the stronger associations for non-serous tumors supports shared biologic mechanisms for tubal ligation and hysterectomy. PMID:24825424

  5. Enhancing the efficiency of sortase-mediated ligations through nickel-peptide complex formation.

    PubMed

    David Row, R; Roark, Travis J; Philip, Marina C; Perkins, Lorena L; Antos, John M

    2015-08-14

    A modified sortase A recognition motif containing a masked Ni(2+)-binding peptide was employed to boost the efficiency of sortase-catalyzed ligation reactions. Deactivation of the Ni(2+)-binding peptide using a Ni(2+) additive improved reaction performance at low to equimolar ratios of the glycine amine nucleophile and sortase substrate. The success of this approach was demonstrated with both peptide and protein substrates. PMID:26152789

  6. Nutcracker syndrome in a patient with a history of inferior vena cava ligation.

    PubMed

    Peker, Ahmet; Yagmurlu, Aydin; Ekim, Mesiha; Gokcora, Haluk; Fitoz, Suat

    2011-09-01

    We report the case of a child with clinical and radiological signs of nutcracker syndrome who had a history of inferior vena cava ligation during a previous surgery. He was referred for evaluation of abdominal pain and hematuria. Entrapment of the left renal vein between the superior mesenteric artery and the aorta with aneurysmal dilatation was detected on Doppler ultrasonography. Magnetic resonance angiography revealed paravertebral and epidural collateral vessels.

  7. Production of dumbbell probe through hairpin cleavage-ligation and increasing RCA sensitivity and specificity by circle to circle amplification

    PubMed Central

    Wei, Hua; Tang, Suming; Hu, Tianyu; Zhao, Guojie; Guan, Yifu

    2016-01-01

    Dumbbell probe (DP) attracts increasing interests in rolling circle amplification (RCA). A universal DP production method through cleavage-ligation of hairpin was proposed and optimized. The production is characterized by restriction endonuclease (RE)-induced cleavage ends ligation. It has the advantage of phosphorylation-free, splint-free and purification-free. To optimize designing, we found that the position of RE cleavage sequence in the stem and the primer position in the loop affected the formation and amplification of DP obviously. Both sticky and blunt ends cleaved by RE produce DP efficiently. Moreover, we introduced this DP into circle to circle (C2C) RCA based on the same cleavage-ligation principle, and acquired high sensitivity. By combining a two-ligation design and the C2C strategy, specificity for detecting let-7 family members was increased extremely. Furthermore, coreaction of different steps facilitated convenient formation and amplification process of DP. PMID:27385060

  8. [Clinical significance and functional outcomes of ligation of exterior carotid artery in surgical treatment of oropharyngeal cancer].

    PubMed

    Klochikhin, A L; Trofimov, E I; Gamilovskaia, Iu V; Chistiakov, A L

    2010-01-01

    This work was designed to analyse outcomes of the treatment of 65 patients with advanced oropharyngeal cancer who had received combined treatment including radical resection of the tumour. Thirty three patients underwent surgery without ligation of exterior carotid artery while the remaining 32 (control group) were operated after preceding ligation of this vessel. The influence of ligation of exterior carotid artery on cerebral circulation was evaluated by the following methods: estimation of the intraoperative blood loss from A.T. Staroverov's formula, ultrasound dopplerography of extracranial carotid segments, electroencephalography, measurement of the fields of vision using statistical quantitative perimetry, evaluation of the patients' neurologic status. It was shown that ligation of exterior carotid artery has no apparent effect on the intraoperative blood loss during radical surgery for the management of oropharyngeal cancer nor does it influence healing of the postoperative wound and oncological outcome of this treatment. PMID:20436415

  9. Controlling Peptide Self-Assembly through a Native Chemical Ligation/Desulfurization Strategy.

    PubMed

    Rasale, Dnyaneshwar B; Konda, Maruthi; Biswas, Sagar; Das, Apurba K

    2016-03-18

    Self-assembled peptides were synthesized by using a native chemical ligation (NCL)/desulfurization strategy that maintained the chemical diversity of the self-assembled peptides. Herein, we employed oxo-ester-mediated NCL reactions to incorporate cysteine, a cysteine-based dipeptide, and a sterically hindered unnatural amino acid (penicillamine) into peptides. Self-assembly of the peptides resulted in the formation of self-supporting gels. Microscopy analysis indicated the formation of helical nanofibers, which were responsible for the formation of gel matrices. The self-assembly of the ligated peptides was governed by covalent and non-covalent interactions, as confirmed by FTIR, CD, fluorescence spectroscopy, and MS (ESI) analyses. Peptide disassembly was induced by desulfurization reactions with tris(2-carboxyethyl)phosphine (TCEP) and glutathione at 80 °C. Desulfurization reactions of the ligated peptides converted the Cys and penicillamine functionalities into Ala and Val moieties, respectively. The self-supporting gels showed significant shear-thinning and thixotropic properties.

  10. Vessel sealing versus suture ligation for canine ovarian pedicle haemostasis: a randomised clinical trial.

    PubMed

    Schwarzkopf, I; Van Goethem, B; Vandekerckhove, P M; de Rooster, H

    2015-01-31

    Vessel sealing (VS) is well established in laparoscopic ovariectomy (OVE) in dogs. The objectives of this study were to evaluate the efficacy of ovarian pedicle haemostasis by VS using a commercially available VS tool in open OVE and compare it with suture ligation (SL). A prospective, randomised clinical trial including 20 female dogs was designed. Open OVE was performed via a standard mid-line celiotomy by a single surgeon using a standardised protocol. At random, the right ovarian pedicle was sealed (VS) or ligated (SL) whereas the left pedicle was treated by the alternative technique. Surgical times for procedural stages and intra-operative complications were recorded and statistically evaluated. Total surgical time was 29.28±11.13 minutes (range 12.50-62.13 minutes) and time from identification to removal of the ovary was significantly less when sealing (VS 2.22±0.58 minutes) than when ligating (SL 4.10±1.13 minutes P=0.0001). Intra-operative complications were rare for both techniques (failure of the electrode of the VS device (n=3); ovarian pedicle haemorrhage due to ligature slippage (n=1)). The results of the current study indicate that ovarian pedicle haemostasis achieved by VS is significantly faster than by placement of ligatures without appearing to compromise safety.

  11. Multiplex, quantitative, ligation-dependent probe amplification for determination of allergens in food.

    PubMed

    Mustorp, Stina L; Drømtorp, Signe M; Holck, Askild L

    2011-05-25

    Legislation requires labeling of foods containing allergenic ingredients. Here, we present a robust 10-plex quantitative and sensitive ligation-dependent probe amplification method, the allergen-multiplex ligation-dependent probe amplification (MLPA) method, for specific detection of eight allergens: sesame, soy, hazelnut, peanut, lupine, gluten, mustard, and celery. Ligated probes were amplified by polymerase chain reaction (PCR), and amplicons were detected using capillary electrophoresis. Quantitative results were obtained by comparing signals with an internal positive control. The limit of detection varied from approximately 5 to 400 gene copies, depending on the allergen. The method was tested using different foods spiked with mustard, celery, soy, or lupine flour in the 1-0.001% range. Depending on the allergen, sensitivities were similar or better than those obtained with qPCR. The allergen-MLPA method is modular and can be adapted by adding probe pairs for other allergens. The DNA-based allergen-MLPA method will constitute a complementary method to the traditional protein-based methods.

  12. Covalent Modification of Synthetic Hydrogels with Bioactive Proteins via Sortase-Mediated Ligation.

    PubMed

    Cambria, Elena; Renggli, Kasper; Ahrens, Caroline C; Cook, Christi D; Kroll, Carsten; Krueger, Andrew T; Imperiali, Barbara; Griffith, Linda G

    2015-08-10

    Synthetic extracellular matrices are widely used in regenerative medicine and as tools in building in vitro physiological culture models. Synthetic hydrogels display advantageous physical properties, but are challenging to modify with large peptides or proteins. Here, a facile, mild enzymatic postgrafting approach is presented. Sortase-mediated ligation was used to conjugate human epidermal growth factor fused to a GGG ligation motif (GGG-EGF) to poly(ethylene glycol) (PEG) hydrogels containing the sortase LPRTG substrate. The reversibility of the sortase reaction was then exploited to cleave tethered EGF from the hydrogels for analysis. Analyses of the reaction supernatant and the postligation hydrogels showed that the amount of tethered EGF increases with increasing LPRTG in the hydrogel or GGG-EGF in the supernatant. Sortase-tethered EGF was biologically active, as demonstrated by stimulation of DNA synthesis in primary human hepatocytes and endometrial epithelial cells. The simplicity, specificity, and reversibility of sortase-mediated ligation and cleavage reactions make it an attractive approach for modification of hydrogels.

  13. Covalent Modification of Synthetic Hydrogels with Bioactive Proteins via Sortase-Mediated Ligation

    PubMed Central

    2015-01-01

    Synthetic extracellular matrices are widely used in regenerative medicine and as tools in building in vitro physiological culture models. Synthetic hydrogels display advantageous physical properties, but are challenging to modify with large peptides or proteins. Here, a facile, mild enzymatic postgrafting approach is presented. Sortase-mediated ligation was used to conjugate human epidermal growth factor fused to a GGG ligation motif (GGG-EGF) to poly(ethylene glycol) (PEG) hydrogels containing the sortase LPRTG substrate. The reversibility of the sortase reaction was then exploited to cleave tethered EGF from the hydrogels for analysis. Analyses of the reaction supernatant and the postligation hydrogels showed that the amount of tethered EGF increases with increasing LPRTG in the hydrogel or GGG-EGF in the supernatant. Sortase-tethered EGF was biologically active, as demonstrated by stimulation of DNA synthesis in primary human hepatocytes and endometrial epithelial cells. The simplicity, specificity, and reversibility of sortase-mediated ligation and cleavage reactions make it an attractive approach for modification of hydrogels. PMID:26098148

  14. Covalent Modification of Synthetic Hydrogels with Bioactive Proteins via Sortase-Mediated Ligation.

    PubMed

    Cambria, Elena; Renggli, Kasper; Ahrens, Caroline C; Cook, Christi D; Kroll, Carsten; Krueger, Andrew T; Imperiali, Barbara; Griffith, Linda G

    2015-08-10

    Synthetic extracellular matrices are widely used in regenerative medicine and as tools in building in vitro physiological culture models. Synthetic hydrogels display advantageous physical properties, but are challenging to modify with large peptides or proteins. Here, a facile, mild enzymatic postgrafting approach is presented. Sortase-mediated ligation was used to conjugate human epidermal growth factor fused to a GGG ligation motif (GGG-EGF) to poly(ethylene glycol) (PEG) hydrogels containing the sortase LPRTG substrate. The reversibility of the sortase reaction was then exploited to cleave tethered EGF from the hydrogels for analysis. Analyses of the reaction supernatant and the postligation hydrogels showed that the amount of tethered EGF increases with increasing LPRTG in the hydrogel or GGG-EGF in the supernatant. Sortase-tethered EGF was biologically active, as demonstrated by stimulation of DNA synthesis in primary human hepatocytes and endometrial epithelial cells. The simplicity, specificity, and reversibility of sortase-mediated ligation and cleavage reactions make it an attractive approach for modification of hydrogels. PMID:26098148

  15. Lipid Raft Is Required for PSGL-1 Ligation Induced HL-60 Cell Adhesion on ICAM-1

    PubMed Central

    Xu, Tingshuang; Liu, Wenai; Luo, Jixian; Li, Chunfeng; Ba, Xueqing; Ampah, Khamal Kwesi; Wang, Xiaoguang; Jiang, Yong; Zeng, Xianlu

    2013-01-01

    P-selectin glycoprotein ligand-1 (PSGL-1) and integrins are adhesion molecules that play critical roles in host defense and innate immunity. PSGL-1 mediates leukocyte rolling and primes leukocytes for integrin-mediated adhesion. However, the mechanism that PSGL-1 as a rolling receptor in regulating integrin activation has not been well characterized. Here, we investigate the function of lipid raft in regulating PSGL-1 induced β2 integrin-mediated HL-60 cells adhesion. PSGL-1 ligation with antibody enhances the β2 integrin activation and β2 integrin-dependent adhesion to ICAM-1. Importantly, with the treatment of methyl-β-cyclodextrin (MβCD), we confirm the role of lipid raft in regulating the activation of β2 integrin. Furthermore, we find that the protein level of PSGL-1 decreased in raft fractions in MβCD treated cells. PSGL-1 ligation induces the recruitment of spleen tyrosine kinase (Syk), a tyrosine kinase and Vav1 (the pivotal downstream effector of Syk signaling pathway involved in cytoskeleton regulation) to lipid raft. Inhibition of Syk activity with pharmacologic inhibitor strongly reduces HL-60 cells adhesion, implicating Syk is crucial for PSGL-1 mediated β2 integrin activation. Taken together, we report that ligation of PSGL-1 on HL-60 cells activates β2 integrin, for which lipid raft integrity and Syk activation are responsible. These findings have shed new light on the mechanisms that connect leukocyte initial rolling with subsequent adhesion. PMID:24312591

  16. Surface ligation-based resonance light scattering analysis of methylated genomic DNA on a microarray platform.

    PubMed

    Ma, Lan; Lei, Zhen; Liu, Xia; Liu, Dianjun; Wang, Zhenxin

    2016-05-10

    DNA methylation is a crucial epigenetic modification and is closely related to tumorigenesis. Herein, a surface ligation-based high throughput method combined with bisulfite treatment is developed for analysis of methylated genomic DNA. In this method, a DNA microarray is employed as a reaction platform, and resonance light scattering (RLS) of nanoparticles is used as the detection principle. The specificity stems from allele-specific ligation of Taq DNA ligase, which is further enhanced by improving the fidelity of Taq DNA ligase in a heterogeneous reaction. Two amplification techniques, rolling circle amplification (RCA) and silver enhancement, are employed after the ligation reaction and a gold nanoparticle (GNP) labeling procedure is used to amplify the signal. As little as 0.01% methylated DNA (i.e. 2 pmol L(-1)) can be distinguished from the cocktail of methylated and unmethylated DNA by the proposed method. More importantly, this method shows good accuracy and sensitivity in profiling the methylation level of genomic DNA of three selected colonic cancer cell lines. This strategy provides a high throughput alternative with reasonable sensitivity and resolution for cancer study and diagnosis.

  17. Ligation of oligonucleotides by pyrimidine dimers--a missing 'link' in the origin of life?

    PubMed

    Lewis, R J; Hanawalt, P C

    1982-07-22

    One of the principal photochemical reactions of DNA on exposure to UV is the formation of intrastrand cyclobutane-type pyrimidine dimers. The efficiency of this reaction depends on both the wavelength of the UV2 and the specific nucleotide sequence in the DNA. The formation of the pyrimidine dimer and its repair in living cells have been studied extensively. We have examined the possibility that pyrimidines at the ends of DNA strands may be adequately juxtaposed for dimer formation by the presence of a complementary strand, even when no phosphodiester linkage joins their sugars. In these conditions the formation of a dimer will 'ligate' two DNA strands end-to-end. We report here that thymidine oligonucleotides annealed to polydeoxyadenylate can be ligated end-to-end by UV irradiation, via thymine dimerization of the terminal nucleotides in adjacent oligonucleotides. The linkages are susceptible to direct photoreversal by 254 nm UV, as expected for cyclobutane-type thymine dimers, but they are not cleaved by the bacteriophage T4 endonuclease V, a dimer-specific DNA repair enzyme. We demonstrate that the ligating dimers are also resistant to photolyase from Escherichia coli. Although the phosphodiester backbone is not required for dimer formation, it is required for recognition of dimers by these DNA repair enzymes. We discuss the possibility that high molecular weight polynucleotides in primordial seas might have been generated from oligonucleotides by pyrimidine dimerization under the intense solar UV flux unattenuated by an ozone layer.

  18. Safety and effectiveness of total splenic vessel ligations in paediatric patients with splenomegaly

    PubMed Central

    Zhen, Chen; Lishuang, Ma; Jinshan, Zhang; Guoliang, Qiao; Wangchen; Zhen, Zhang; Shuili, Liu; Jun, Zhang; Kaoping, Guan; Long, Li

    2016-01-01

    BACKGROUNDS: Splenomegaly may contribute to hypersplenism and can result in thrombocytopenia. Many approaches are used to treat splenomegaly; however, the current management of splenomegaly has intrinsic limitations or disadvantages. Now, we initiate a new approach, that of total splenic vessel (artery and vein) ligations (TSVLs) in paediatric patients with splenomegaly. The purpose of our study is to evaluate the results obtained with TVSLs procedure for paediatric patients. PATIENTS AND METHODS: Seventeen paediatric patients with splenomegaly were screened for enrolment into this retrospective analysis. PROCEDURE: We identified and dissociated the splenic vessel. Next, we ligated the splenic artery and we used clips to ligate the vein distally and proximally. RESULT: The mean [standard deviation (SD)] splenic infarction rate of a total of 17 patients was 77.5 (5.1)% in 6 months after operation. After TSVL, the mean count of platelet (PLT) and white blood cell (WBC) increased significantly and reached a steady state in the third month. Both the PLT and WBC had a significance higher than pre-TSVL in a 1-year follow-up. CONCLUSION: Based on the evidence, we make cautious conclusions that TSVLs are a safe and effective method in the treatment of paediatric patients with splenomegaly, achieving a satisfactory long-term haematological response and benefit. PMID:27609328

  19. Psychosocial implications of tubal ligation in a rural health district: A phenomenological study

    PubMed Central

    2011-01-01

    Background Tubal ligation is the most popular family planning method worldwide. While its benefits, such as effectiveness in protecting against pregnancies, minimal need for long-term follow-up and low side-effects profile are well documented, it has many reported complications. However, to date, these complications have not been described by residents in Congo. Therefore, the study aimed at exploring the experience of women who had undergone tubal ligation, focusing on perceptions of physical, psychological and contextual experiences of participants. Methods This qualitative study used a semi-structured questionnaire in a phenomenological paradigm to collect data. Fifteen participants were purposefully selected among sterilized women who had a ligation procedure performed, were aged between 30 and 40 years, and were living within the catchment area of the district hospital. Data were collected by two registered nurses, tape-recorded, and transcribed verbatim. Reading and re-reading cut and paste techniques, and integration were used to establish codes, categories, themes, and description. Results Diverse and sometimes opposite changes in somatic symptoms, psychological symptoms, productivity, ecological relationships, doctor-client relationships, ethical issues, and change of life style were the major problem domains. Conclusions Clients reported conflicting experiences in several areas of their lives after tubal sterilization. Management, including awareness of the particular features of the client, is needed to decrease the likelihood of psychosocial morbidity and/or to select clients in need of sterilization. PMID:22176816

  20. pH-degradable imidazoquinoline-ligated nanogels for lymph node-focused immune activation.

    PubMed

    Nuhn, Lutz; Vanparijs, Nane; De Beuckelaer, Ans; Lybaert, Lien; Verstraete, Glenn; Deswarte, Kim; Lienenklaus, Stefan; Shukla, Nikunj M; Salyer, Alex C D; Lambrecht, Bart N; Grooten, Johan; David, Sunil A; De Koker, Stefaan; De Geest, Bruno G

    2016-07-19

    Agonists of Toll-like receptors (TLRs) are potent activators of the innate immune system and hold promise as vaccine adjuvant and for anticancer immunotherapy. Unfortunately, in soluble form they readily enter systemic circulation and cause systemic inflammatory toxicity. Here we demonstrate that by covalent ligation of a small-molecule imidazoquinoline-based TLR7/8 agonist to 50-nm-sized degradable polymeric nanogels the potency of the agonist to activate TLR7/8 in in vitro cultured dendritic cells is largely retained. Importantly, imidazoquinoline-ligated nanogels focused the in vivo immune activation on the draining lymph nodes while dramatically reducing systemic inflammation. Mechanistic studies revealed a prevalent passive diffusion of the nanogels to the draining lymph node. Moreover, immunization studies in mice have shown that relative to soluble TLR7/8 agonist, imidazoquinoline-ligated nanogels induce superior antibody and T-cell responses against a tuberculosis antigen. This approach opens possibilities to enhance the therapeutic benefit of small-molecule TLR agonist for a variety of applications. PMID:27382168

  1. A functional model for the cysteinate-ligated non-heme iron enzyme superoxide reductase (SOR).

    PubMed

    Kitagawa, Terutaka; Dey, Abhishek; Lugo-Mas, Priscilla; Benedict, Jason B; Kaminsky, Werner; Solomon, Edward; Kovacs, Julie A

    2006-11-15

    Superoxide reductases (SORs) are cysteine-ligated, non-heme iron enzymes that reduce toxic superoxide radicals (O2-). The functional role of the trans cysteinate, as well as the mechanism by which SOR reduces O2-, is unknown. Herein is described a rare example of a functional metalloenzyme analogue, which catalytically reduces superoxide in a proton-dependent mechanism, via a trans thiolate-ligated iron-peroxo intermediate, the first example of its type. Acetic-acid-promoted H2O2 release, followed by Cp2Co reduction, regenerates the active Fe(II) catalyst. The thiolate ligand and its trans positioning relative to the substrate are shown to contribute significantly to the catalyst's function, by lowering the redox potential, changing the spin state, and dramatically lowering the nuFe-O stretching frequency well-below that of any other reported iron-peroxo, while leaving nuO-O high, so as to favor superoxide reduction and Fe-O, as opposed to O-O, bond cleavage. Thus we provide critical insight into the relationship between the SOR structure and its function, as well as important benchmark parameters for characterizing highly unstable thiolate-ligated iron-peroxo intermediates. PMID:17090014

  2. Mechanistic insights of rapid liver regeneration after associating liver partition and portal vein ligation for stage hepatectomy

    PubMed Central

    Moris, Demetrios; Vernadakis, Spyridon; Papalampros, Alexandros; Vailas, Michail; Dimitrokallis, Nikolaos; Petrou, Athanasios; Dimitroulis, Dimitrios

    2016-01-01

    AIM To highlight the potential mechanisms of regeneration in the Associating Liver Partition and Portal vein ligation for Stage hepatectomy models (clinical and experimental) that could unlock the myth behind the extraordinary capability of the liver for regeneration, which would help in designing new therapeutic options for the regenerative drive in difficult setup, such as chronic liver diseases. Associating Liver Partition and Portal vein ligation for Stage hepatectomy has been recently advocated to induce rapid future liver remnant hypertrophy that significantly shortens the time for the second stage hepatectomy. The introduction of Associating Liver Partition and Portal vein ligation for Stage hepatectomy in the surgical armamentarium of therapeutic tools for liver surgeons represented a real breakthrough in the history of liver surgery. METHODS A comprehensive literature review of Associating Liver Partition and Portal vein ligation for Stage hepatectomy and its utility in liver regeneration is performed. RESULTS Liver regeneration after Associating Liver Partition and Portal vein ligation for Stage hepatectomy is a combination of portal flow changes and parenchymal transection that generate a systematic response inducing hepatocyte proliferation and remodeling. CONCLUSION Associating Liver Partition and Portal vein ligation for Stage hepatectomy represents a real breakthrough in the history of liver surgery because it offers rapid liver regeneration potential that facilitate resection of liver tumors that were previously though unresectable. The jury is still out though in terms of safety, efficacy and oncological outcomes. As far as Associating Liver Partition and Portal vein ligation for Stage hepatectomy -induced liver regeneration is concerned, further research on the field should focus on the role of non-parenchymal cells in liver regeneration as well as on the effect of Associating Liver Partition and Portal vein ligation for Stage hepatectomy in liver

  3. Encoded Library Synthesis Using Chemical Ligation and the Discovery of sEH Inhibitors from a 334-Million Member Library

    PubMed Central

    Litovchick, Alexander; Dumelin, Christoph E.; Habeshian, Sevan; Gikunju, Diana; Guié, Marie-Aude; Centrella, Paolo; Zhang, Ying; Sigel, Eric A.; Cuozzo, John W.; Keefe, Anthony D.; Clark, Matthew A.

    2015-01-01

    A chemical ligation method for construction of DNA-encoded small-molecule libraries has been developed. Taking advantage of the ability of the Klenow fragment of DNA polymerase to accept templates with triazole linkages in place of phosphodiesters, we have designed a strategy for chemically ligating oligonucleotide tags using cycloaddition chemistry. We have utilized this strategy in the construction and selection of a small molecule library, and successfully identified inhibitors of the enzyme soluble epoxide hydrolase. PMID:26061191

  4. Encoded Library Synthesis Using Chemical Ligation and the Discovery of sEH Inhibitors from a 334-Million Member Library.

    PubMed

    Litovchick, Alexander; Dumelin, Christoph E; Habeshian, Sevan; Gikunju, Diana; Guié, Marie-Aude; Centrella, Paolo; Zhang, Ying; Sigel, Eric A; Cuozzo, John W; Keefe, Anthony D; Clark, Matthew A

    2015-01-01

    A chemical ligation method for construction of DNA-encoded small-molecule libraries has been developed. Taking advantage of the ability of the Klenow fragment of DNA polymerase to accept templates with triazole linkages in place of phosphodiesters, we have designed a strategy for chemically ligating oligonucleotide tags using cycloaddition chemistry. We have utilized this strategy in the construction and selection of a small molecule library, and successfully identified inhibitors of the enzyme soluble epoxide hydrolase. PMID:26061191

  5. Ultrasensitive detection of DNA and RNA based on enzyme-free click chemical ligation chain reaction on dispersed gold nanoparticles.

    PubMed

    Kato, Daiki; Oishi, Motoi

    2014-10-28

    An ultrasensitive colorimetric DNA and RNA assay using a combination of enzyme-free click chemical ligation chain reaction (CCLCR) on dispersed gold nanoparticles (GNPs) and a magnetic separation process has been developed. The click chemical ligation between an azide-containing probe DNA-modified GNP and a dibenzocyclooctyne-containing probe biotinyl DNA occurred through hybridization with target DNA (RNA) to form the biotinyl-ligated GNPs (ligated products). Eventually, both the biotinyl-ligated GNPs and target DNA (RNA) were amplified exponentially using thermal cycling. After separation of the biotinyl-ligated GNPs using streptavidin-modified magnetic beads, the change in intensity of the surface plasmon band at 525 nm in the supernatants was observed by UV/vis measurement and was also evident visually. The CCLCR assay provides ultrasensitive detection (50 zM: several copies) of target DNA that is comparable to PCR-based approaches. Note that target RNA could also be detected with similar sensitivity without the need for reverse transcription to the corresponding cDNA. The amplification efficiency of the CCLCR assay was as high as 82% due to the pseudohomogeneous reaction behavior of CCLCR on dispersed GNPs. In addition, the CCLCR assay was able to discriminate differences in single-base mismatches and to specifically detect target DNA and target RNA from the cell lysate.

  6. In vitro evaluation of resistance to sliding in self-ligating and conventional bracket systems during dental alignment

    PubMed Central

    Cordasco, Giancarlo; Lo Giudice, Antonino; Militi, Angela; Nucera, Riccardo; Triolo, Giuseppe

    2012-01-01

    Objective To investigate the resistance to sliding (RS) in self-ligating and conventional ligation bracket systems at 5 different second-order bracket angulations by using low-stiffness alignment wires in a 3-bracket experimental model and to verify the performance of the main RS components in both systems when these wires are used. Methods Interactive self-ligating brackets with closed and open slides were used for the self-ligating (SL) and conventional ligation (CL) groups, respectively; elastomeric ligatures (1 mm inner diameter) were used in the latter system. The alignment wire used was 0.014 inch heat-activated NiTi (austenitic finish temperature set at 36℃ by the manufacturer). A custom-made testing machine was used to measure frictional resistance. Tests were repeated 5 times at every angulation simulated. All data were analyzed statistically. Results The RS increased significantly with increasing angulation in both SL and CL groups (p < 0.0001). However, the RS values were significantly higher at every angulation (p < 0.0001) in the CL group. Conclusions Despite the relevance of the binding phenomenon, ligation forces predominantly affect the RS when low-stiffness alignment wires are used. PMID:23112953

  7. [The present practice of tubal ligation in West German university departments of obstetrics and gynaecology (author's transl)].

    PubMed

    Kunz, S; Probst, V

    1975-12-01

    Within a few years the attitudes of the general public and the majority of the physicians to tubal ligation have undergone radical change. The present indications, incidence and policies of tubal ligation in 21 west german University Departments were explored by questionnaire. A survey on the incidence of tubal ligation in large departments of Obstetrics and Gynaecology was obtained prior to the enactment of new laws and regulations. The reported figures show a steep rise in the incidence of tubal ligation from 1970 to 1974. This fact is partially due to a very liberal interpretation of medical indications and partly due to the acceptance of tubal ligation as permanent contraception under certain individual and family conditions. The results of the enquiry are interpreted as the present practice of regulations which are legally still in the planning stage. In spite of the liberalization of the indications for tubal ligation, problems such as individual psychological difficulties associated with female sterilization cannot be minimized. Therefore the majority of the departments demand an intensive explanatory session and detailed informed consent for female sterilization.

  8. Nonenzymatic, template-directed ligation of oligoribonucleotides is highly regioselective for the formation of 3'-5' phosphodiester bonds

    NASA Technical Reports Server (NTRS)

    Rohatgi, R.; Bartel, D. P.; Szostak, J. W.

    1996-01-01

    We have found that nonenzymatic, template-directed ligation reactions of oligoribonucleotides display high selectivity for the formation of 3'-5' rather than 2'-5' phosphodiester bonds. Formation of the 3'-5'-linked product is favored regardless of the metal ion catalyst or the leaving group, and for several different ligation junction sequences. The degree of selectivity depends on the leaving group: the ratio of 3'-5'- to 2'-5'-linked products was 10-15:1 when the 5'-phosphate was activated as the imidazolide, and 60-80:1 when the 5'-phosphate was activated by the formation of a 5'-triphosphate. Comparison of oligonucleotide ligation reactions with previously characterized single nucleotide primer extension reactions suggests that the strong preference for 3'-5'-linkages in oligonucleotide ligation is primarily due to occurence of ligation within the context of an extended Watston-Crick duplex. The ability of RNA to correctly self-assemble by template-directed ligation is an intrinsic consequence of its chemical structure and need not be imposed by an external catalyst (i.e., an enzyme polymerase); RNA therefore provides a reasonable structural basis for a self-replicating system in a prebiological world.

  9. Is portal-systemic shunt worthwhile in Child's class C cirrhosis? Long-term results of emergency shunt in 94 patients with bleeding varices.

    PubMed Central

    Orloff, M J; Orloff, M S; Rambotti, M; Girard, B

    1992-01-01

    A prospective evaluation was conducted of 94 unselected patients ("all comers") with biopsy-proven Child's class C cirrhosis (93% alcoholic) and endoscopically proven acutely bleeding esophageal varices who underwent emergency portacaval shunt (EPCS) (85% side-to-side, 15% end-to-side) within 8 hours of initial contact (mean, 6.1 hours) during the past 12 years. Follow-up has been 100% and includes all patients for at least 1 year, and 61 patients (65%) for 5 to 12 years. Incidence of serious risk factors on initial contact was: ascites, 97%; jaundice, 86%; portal-systemic encephalopathy including past history, 71%; severe muscle wasting, 96%; alcohol ingestion within 7 days, 66%; delirium tremens, 16%; serum albumin, less than or equal to 2.5 g/dL 76%; indocyanine green dye retention greater than or equal to 50% in 45 minutes, 66%; serum glutamic-oxaloacetic transaminase greater than or equal to 100 units/L, 60%; hyperdynamic cardiac output greater than or equal to 6 L/minute, 98%. Mean Child's point score was 13.7 out of a maximum of 15. EPCS reduced mean corrected free portal pressure from 286 to 23 mm saline, and permanently controlled variceal bleeding in every patient. Of the 94 patients, 74 (80%) left the hospital alive and 68 (72%) survived 1 year. Five-year actuarial survival rate is 64%. Hepatic failure was the main cause of death during initial hospitalization as well as during follow-up, when it was related to continued alcoholism. Portal-systemic encephalopathy, which was present on initial contact in 55% of patients, occurred at some time during follow-up in 18.7%, but was recurrent and required dietary protein restriction in only 9%, all of whom had resumed alcoholism. The low incidence of portal-systemic encephalopathy was attributable to the lifelong program of follow-up with regular dietary counseling and continued emphasis on both protein restriction to 60 g/day and abstinence from alcohol. Abstinence was sustained in 69%, liver function improved

  10. Bilateral uterine vessel ligation as a model of intrauterine growth restriction in mice

    PubMed Central

    2014-01-01

    Background Intrauterine Growth Restriction (IUGR) occurs in up to 10% of pregnancies and is considered as a major risk to develop various diseases in adulthood, such as cardiovascular diseases, insulin resistance, hypertension or end stage kidney disease. Several IUGR models have been developed in order to understand the biological processes linked to fetal growth retardation, most of them being rat or mouse models and nutritional models. In order to reproduce altered placental flow, surgical models have also been developed, and among them bilateral uterine ligation has been frequently used. Nevertheless, this model has never been developed in the mouse, although murine tools display multiple advantages for biological research. The aim of this work was therefore to develop a mouse model of bilateral uterine ligation as a surgical model of IUGR. Results In this report, we describe the set up and experimental data obtained from three different protocols (P1, P2, P3) of bilateral uterine vessel ligation in the mouse. Ligation was either performed at the cervical end of each uterine horn (P1) or at the central part of each uterine horn (P2 and P3). Time of surgery was E16 (P1), E17 (P2) or E16.5 (P3). Mortality, maternal weight and abortion parameters were recorded, as well as placentas weights, fetal resorption, viability, fetal weight and size. Results showed that P1 in test animals led to IUGR but was also accompanied with high mortality rate of mothers (50%), low viability of fetuses (8%) and high resorption rate (25%). P2 and P3 improved most of these parameters (decreased mortality and improved pregnancy outcomes; improved fetal viability to 90% and 27%, respectively) nevertheless P2 was not associated to IUGR contrary to P3. Thus P3 experimental conditions enable IUGR with better pregnancy and fetuses outcomes parameters that allow its use in experimental studies. Conclusions Our results show that bilateral uterine artery ligation according to the protocol we

  11. Compliance with Papanicolaou smear screening following tubal ligation in women with cervical cancer.

    PubMed

    Winkler, H A; Anderson, P S; Fields, A L; Runowicz, C D; DeVictoria, C; Goldberg, G L

    1999-01-01

    To evaluate patient compliance with Papanicolaou (Pap) smear screening after tubal ligation compared with other methods of birth control in patients who develop cervical cancer, a retrospective review of 262 women with cervical cancer diagnosed at age < or = 70 years was undertaken at the Albert Einstein College of Medicine from January 1987 to December 1995. Demographic data, stage of the disease, histologic type, history of smoking, history of sexually transmitted disease (STD), and birth control use were recorded. The Pap screening history was obtained from all the patients. Women who had a bilateral tubal ligation (BTL) were compared with those who did not have this form of birth control. The date and result of their last Pap test prior to their diagnosis of cervical cancer was noted. Two hundred fourteen women with cervical cancer were evaluable. The clinical stage, mean age, history of smoking, and history of STD were similar for both groups. Gravidity among the BTL group was higher than in the non-BTL group (p < 0.01). Forty-eight (22.4%) women had a previous BTL. Twenty-seven of these 48 patients (56.3%) did not have a Pap smear within 3 years prior to the diagnosis of cervical cancer. Of the 166 patients, 61 (36.7%) did not have a Pap test within 3 years (p < 0.05). Fourteen women (29.2%) in the tubal ligation group never returned for a Pap test following the BTL. An average of 6.2+/-5.9 years elapsed since the last Pap test in the BTL group, with 4.0+/-5.1 years in the nontubal ligation group (p < 0.05). There was a correlation between the number of years since BTL (14.2+/-7.7) to the number of years since the last Pap test (6.2+/-5.9) (p < 0.05). Women who have had a BTL should be considered high risk because of poor screening compliance. A Pap test every 3 years is not adequate in this high-risk population group. We advocate improved counseling regarding the importance of continued annual Pap screening for women who are considering tubal ligation. PMID

  12. Is the ligation of hernial sac necessary in herniotomy for children? A randomized controlled trial of evaluating surgical complications and duration

    PubMed Central

    Rafiei, Mohammad Hadi; Jazini, Ali

    2015-01-01

    Background: Herniotomy is a common operation done by pediatric surgeons. Recent studies have shown that high ligation in herniation in adult is not necessary, but this method was not fully evaluated in children. We compared non-ligation with high-ligation sac in herniotomy in terms of surgical complications and duration. Materials and Methods: This randomized controlled trial study was done on 104 children with inguinal hernia at Al-Zahra Hospital, Isfahan, Iran, between 2011 and 2013. Patients were equally randomized to undergo herniotomy with ligation of sac at the internal ring level or to undergo herniotomy without sac ligation. Patients were followed up just after the operation, and in the 1st, 6th, and 12th weeks postoperation to discover early (scrotal hematoma, edema, wound infection, and postoperation fever) and late (adhesion and recurrence) complications. Also, duration of operation was recorded for each group. Results: The incidence of early complications (nine cases in high-ligation and eight cases in non-ligation group) was the same in both groups (P = 0.402). No late complication was observed in any group. The mean duration of operation in high-ligation group (18.84 ± 5.47 min) was significantly shorter than non-ligation group (21.46 ± 9.03 min) (P < 0.001). Conclusion: Complications are the same in herniotomy with or without ligation of the sac, but the duration of the non-ligation procedure is shorter than that of high-ligation. We suggest that herniotomy without sac ligation in children be the procedure of choice to save time and also to prevent any other possible complications such as nerve damage, spermatic cord injury, or peritoneal tearing. PMID:26015923

  13. A totally laparoscopic associating liver partition and portal vein ligation for staged hepatectomy assisted with radiofrequency (radiofrequency assisted liver partition with portal vein ligation) for staged liver resection

    PubMed Central

    Hakim, David N.; Gall, Tamara M. H.; Fajardo, Ana; Pencavel, Tim D.; Fan, Ruifang; Sodergren, Mikael H.

    2016-01-01

    In order to induce liver hypertrophy to enable liver resection in patients with a small future liver remnant (FLR), various methods have been proposed in addition to portal vein embolisation (PVE). Most recently, the associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) technique has gained significant international interest. This technique is limited by the high morbidity associated with an in situ liver splitting and the patient undergoing two open operations. We present the case of a variant ALPPS technique performed entirely laparoscopically with no major morbidity or mortality. An increased liver volume of 57.9% was seen after 14 days. This technique is feasible to perform and compares favourably to other ALPPS methods whilst gaining the advantages of laparoscopic surgery. PMID:27500150

  14. Effects of portal vein ligation on sex hormone metabolism in male rats: relationship to lowered hepatic cytochrome P450 levels.

    PubMed

    Farrell, G C; Koltai, A; Zaluzny, L; Murray, M

    1986-02-01

    Hepatic cytochrome P450 levels in male rats fall after portal vein ligation, a procedure that produces total hepatic bypass of portal blood. The present study was undertaken to examine whether changes in sex hormone metabolism could account for these lowered cytochrome P450 levels. Portal vein ligation resulted in testicular atrophy and low serum testosterone concentrations. Serum luteinizing hormone levels were also reduced, suggesting that testicular atrophy was secondary to suppression of the hypothalamic-pituitary-gonadal axis. Serum estrone and estradiol concentrations were significantly increased after portal vein ligation, while the magnitude and delayed onset of increases in urinary total estrogen excretion suggested that this was due largely to increased estrogen production. In male rats, both castration (at 12 wk) and exogenous estrogen administration resulted in changes in hepatic cytochrome P450 levels and ethylmorphine N-demethylase activity that were qualitatively similar to those seen after portal vein ligation. In female and castrated male rats, however, cytochrome P450 was not affected by portal vein ligation. Testosterone supplementation corrected the changes of cytochrome P450 levels in castrated male rats but did not have this effect in portal vein-ligated male rats. It is concluded that changes in sex hormone metabolism do occur after portal vein ligation and may contribute to alterations in cytochrome P450 and drug-metabolizing enzyme activity. Decreased levels of serum testosterone, however, do not alone account for the changes in hepatic drug metabolism in this model, and suppression of a hypothalamic-pituitary factor appears to be important.

  15. A comparative in-vivo evaluation of the alignment efficiency of 5 ligation methods: A prospective randomized clinical trial

    PubMed Central

    Reddy, Vijaya Bhaskara; Kumar, Talapaneni Ashok; Prasad, Mandava; Nuvvula, Sivakumar; Patil, Rajedra Goud; Reddy, Praveen Kumar

    2014-01-01

    Objectives: To conduct a prospective randomized study comparing the efficiency of 5 different ligation systems (ELL; elastomeric ligature, SSL; stainless steel ligature, LL; leone slide ligature, PSL; passive self-ligation and ASL; active self-ligation) over the duration of mandibular crowding alleviation. Materials and Methods: Fifty consecutive patients (54.2% male, 45.8% female; mean age: 16.69 years) satisfying the inclusion criteria were randomly allocated to 5 ligation groups with an equal sample size of 10 per group. The 5 groups received treatment with 0.022-inch MBT pre-adjusted edge-wise technique (ELL: Gemini 3M Unitek, SSL: Gemini 3M Unitek, LL: Gemini 3M Unitek, PSL: SmartClip 3M Unitek and ASL: In-Ovation R Euro GAC International). The models and cephalograms were evaluated for anterior arch alignment, extraction space closure, and lower incisal inclinations at pre-treatment T1 and at the end of initial alignment T2. Analysis of variance (ANOVA) and Post-hoc tests were used for data analysis. Results: Forty-eight participants completed the study, and SL systems showed a significant difference over CL groups in time to alignment, passive space closure, and incisal inclination. Multiple regression showed a reduction of 5.28 days in time to alignment by changing the ligation group in the order of ELL to ASL group and 1 mm increase in initial irregularity index increases time to alignment by 11.68 days. Conclusion: Self-ligation brackets were more efficient than conventional ligation brackets during initial leveling and alignment. PMID:24966742

  16. Evidence of Liquid Crystal-Assisted Abiotic Ligation of Nucleic Acids

    NASA Astrophysics Data System (ADS)

    Fraccia, Tommaso P.; Zanchetta, Giuliano; Rimoldi, Valeria; Clark, Noel A.; Bellini, Tommaso

    2015-06-01

    The emergence of early life must have been marked by the appearance in the prebiotic era of complex molecular structures and systems, motivating the investigation of conditions that could not only facilitate appropriate chemical synthesis, but also provide the mechanisms of molecular selection and structural templating necessary to pilot the complexification toward specific molecular patterns. We recently proposed and demonstrated that these functions could be afforded by the spontaneous ordering of ultrashort nucleic acids oligomers into Liquid Crystal (LC) phases. In such supramolecular assemblies, duplex-forming oligomers are held in average end-to-end contact to form chemically discontinuous but physically continuous double helices. Using blunt ended duplexes, we found that LC formation could both provide molecular selection mechanisms and boost inter-oligomer ligation. This paper provides an essential extension to this notion by investigating the catalytic effects of LC ordering in duplexes with mutually interacting overhangs. Specifically, we studied the influence of LC ordering of 5'-hydroxy-3'-phosphate partially self-complementary DNA 14mers with 3'-CG sticky-ends, on the efficiency of non-enzymatic ligation reaction induced by water-soluble carbodiimide EDC as condensing agent. We investigated the ligation products in mixtures of DNA with poly-ethylene glycol (PEG) at three PEG concentrations at which the system phase separates creating DNA-rich droplets that organize into isotropic, nematic LC and columnar LC phases. We observe remarkable LC-enhanced chain lengthening, and we demonstrate that such lengthening effectively promotes and stabilizes LC domains, providing the kernel of a positive feedback cycle by which LC ordering promotes elongation, in turn stabilizing the LC ordering.

  17. SADI-S WITH RIGHT GASTRIC ARTERY LIGATION: TECHNICAL SYSTEMATIZATION AND EARLY RESULTS

    PubMed Central

    GEBELLI, Jordi Pujol; de GORDEJUELA, Amador Garcia Ruiz; RAMOS, Almino Cardoso; NORA, Mario; PEREIRA, Ana Marta; CAMPOS, Josemberg Marins; RAMOS, Manoela Galvão; BASTOS, Eduardo Lemos de Souza; MARCHESINI, João Batista

    2016-01-01

    ABSTRACT Background: Bariatric surgery is performed all over the world with close to 500.000 procedures per year. The most performed techniques are Roux-en-Y gastric bypass and sleeve gastrectomy. Despite this data, the most effective procedure, biliopancreatic diversion with or without duodenal switch, represents only no more than 1.5% of the procedures. Technical complexity, morbidity, mortality, and severe nutritional adverse effects related to the procedure are the main fears that prevent most universal acceptance. Aim: To explain the technical aspects and the benefits of the SADI-S with right gastric artery ligation as an effective simplification from the original duodenal switch. Methods: Were included all patients undergoing this procedure from the November 2014 to May 2016, describing and analysing aspects of this technique, the systematization and early complications associated with the procedure. Results: A series of 67 patients were operated; 46 were women (68.7%); mean age of the group was 44 years old (33-56); and an average BMI of 53.5 kg/m2 (50-63.5). Surgical time was 115 min (80-180). A total of five patients (7.5%) had any complication and two (2.9%) had to be reoperated. There were two patients with leak, one at the duodenal stump and other at the esophagogastric angle. There was no mortality. Patients stayed at the hospital a median of 2.5 days (1-25). Conclusions: SADI-S with right gastric artery ligation is a safe procedure with few preliminary complications. The technical variations introduced to the classical duodenal switch are reproducible and may allow this procedure to be more popular. All the complications in this series were not related to the ligation of the right gastric artery. PMID:27683784

  18. Isolation of pathogen-induced Chinese cabbage genes by subtractive hybridization employing selective adaptor ligation.

    PubMed

    Ryang, Seung Ho; Chung, Sam Young; Lee, Sung Hee; Cha, Jae Soon; Yong Kim, Hak; Cho, Tae Ju

    2002-12-01

    We have developed a subtractive cloning method in which target sequences are effectively enriched by selective adaptor ligation and PCR after hybridization. In this method both tester and driver DNAs are digested with RsaI, ligated with the linker DNA containing a KpnI recognition site, and amplified by PCR. The tester DNA samples are divided into two aliquots, each digested with either RsaI or KpnI. The two DNA samples are then combined and hybridized with an excess of the driver DNA retaining the linker. After hybridization, the DNA mixture is ligated to a new adaptor compatible only with double-stranded tester/tester DNAs. Therefore, only the tester/tester is selectively amplified in subsequent PCR. This also leads to complete elimination of the tester DNA hybridized with driver DNA from the tester DNA population. Although our protocol employs enzymatic treatments, the efficiency of the enzymatic treatments does not affect the subtraction efficiency. This new subtractive enrichment method was applied to isolate Chinese cabbage defense-related genes induced by Pseudomonas syringae pv. tomato (Pst), which elicits a hypersensitive response in Chinese cabbage. After two or three rounds of subtractive hybridization, the sequences of enriched DNAs were determined and examined by BLAST analysis. Northern blot hybridization showed that 12 of the 19 genes analyzed were strongly induced by Pst treatment. Among the 12 Pst-induced genes five represent pathogenesis-related genes encoding PR1a, two chitinases, a thaumatin-like protein, and a PR4 protein. Other Pst-induced genes include two cytochrome P450 genes responsible for glucosinolate biosynthesis, a disease resistance gene homolog, and several genes encoding proteins with unknown functions.

  19. Comparative assessment of forces generated during simulated alignment with self-ligating and conventional brackets.

    PubMed

    Pandis, Nikolaos; Eliades, Theodore; Bourauel, Christoph

    2009-12-01

    The objectives of this study were to comparatively assess the magnitude and direction of forces and moments generated from different bracket systems, during the initial levelling and alignment stage of orthodontic treatment. Three types of brackets were used: Orthos2 (Ormco), Damon2 (Ormco), and In-Ovation R (GAC). The brackets were bonded on resin replicas models of a patient's crowded mandibular arch, and a 0.014 inch Damon archform CuNiTi (Ormco) wire was inserted. The model was mounted on the Orthodontic Measurement and Simulation System (OMSS) and six static measurements were taken at the initial crowded state per bracket for the lateral incisor, canine, and first premolar. A total of 10 repetitions were performed for each measurement, with new brackets and archwires used for each trial. The forces and moments generated were registered directly on the OMSS software and were statistically analyzed using a one-way analysis of variance separately for each dental arch location and force component. Group differences were further analyzed with Tukey's post hoc comparisons test at the 0.05 significance level. The lingually inclined, crowded lateral incisor presented an extrusive and buccal movement and showed the lowest force in the vertical direction, whereas the self-ligating group of brackets generated the highest force in the buccolingual direction. The moments applied by the three bracket systems followed the general trend shown for forces; in the vertical axis, the self-ligating brackets exerted lower forces than their conventional counterpart. This was modified in the buccolingual direction where, in most instances, the self-ligating appliances applied higher moments compared with the conventional bracket. In most cases, the magnitude of forces and moments ranged between 30-70 cN and 2-6 N mm, respectively. However, maximum forces and moments developed at the lateral incisor were almost four times higher than the average. PMID:19349418

  20. Optimal Duration of Coronary Ligation and Reperfusion for Reperfusion Injury Study in a Rat Model

    PubMed Central

    Chang, Shih-Tai; Chu, Chi-Ming; Yang, Teng-Yao; Hung, Li-Man; Pan, Kuo-Li; Cherng, Wen-Jin

    2016-01-01

    Background Reperfusion injury (RI) has an important impact on the clinical prognosis for patients with acute myocardial injury who had their coronary blood flow reestablished. However, no studies to date have investigated the timeframe of coronary occlusion and reperfusion effects on RI. Methods A total of 100 rats were divided into 4 groups based on the coronary ligation period: 30, 60, 120, and 180 min, and each group was further divided into 5 subgroups with different reperfusion periods: 0, 30, 60, 120, and 180 min. R0 was the baseline of each subgroup. All animals received the same protocols for designed ligation and reperfusion periods. Evans blue and 2,3,5-triphenyltetrazolium chloride were used to distinguish different myocardial injury areas: area at risk (AAR) and myocardial necrosis. The differences of the ratios of the necrotic area to AAR between each subgroup and baseline were further averaged to calculate an overall value of each heart. Results The relative RI percentages showed significant differences (0.8 ± 2.3%, 4.9 ± 3.3%, 10.8 ± 3.1%, and 20.3 ± 3.6% respectively, p < 0.001) at different time points of reperfusion but not at different time points of ligation (p = 0.593). The effects of different time courses in RI showed that the L120R180 group (43.4 ± 2.3%) had the highest RI difference with the baseline group. Conclusions Maximal RI occurred at the timeframe of L120R180 in our animal model. This result may be utilized to assess the substantial benefits of RI therapies in an experimental rat model setting. PMID:27471363

  1. Development and validation of an oligonucleotide ligation assay to detect lamivudine resistance in hepatitis B virus.

    PubMed

    Beck, Ingrid A; Payant, Rachel; Ngo-Giang-Huong, Nicole; Khamduang, Woottichai; Laomanit, Laddawan; Jourdain, Gonzague; Frenkel, Lisa M

    2016-07-01

    Treatment of chronic hepatitis B virus (HBV) infection with lamivudine-monotherapy rapidly selects mutant variants in a high proportion of individuals. Monitoring lamivudine resistance by consensus sequencing is costly and insensitive for detection of minority variants. An oligonucleotide ligation assay (OLA) for HBV lamivudine-resistance was developed and compared to consensus sequencing. Both assays detected drug resistance mutations in 35/64 (54.7%) specimens evaluated, and OLA detected minority mutants in an additional six (9.4%). OLA may offer a sensitive and inexpensive alternative to consensus sequencing for detection of HBV drug resistance in resource-limited settings. PMID:27025356

  2. A Novel Method to Quantify RNA-Protein Interactions In Situ Using FMTRIP and Proximity Ligation.

    PubMed

    Zurla, C; Jung, J; Blanchard, E L; Santangelo, P J

    2017-01-01

    RNA binding proteins (RBP) and small RNAs regulate the editing, localization, stabilization, translation, and degradation of ribonucleic acids (RNAs) through their interactions with specific cis-acting elements within target RNAs. Here, we describe a novel method to detect protein-mRNA interactions, which combines FLAG-peptide modified, multiply-labeled tetravalent RNA imaging probes (FMTRIPs) with proximity ligation (PLA), and rolling circle amplification (RCA). This assay detects native RNA in a sequence specific and single RNA sensitive manner, and PLA allows for the quantification and localization of protein-mRNA interactions with single-interaction sensitivity. PMID:27662876

  3. Is it safe to divide and ligate the left innominate vein in complex cardiothoracic surgeries?

    PubMed Central

    McPhee, Arthur; Shaikhrezai, Kasra; Berg, Geoffrey

    2013-01-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether it is safe to divide the left innominate vein (LIV) in aortic arch surgery to improve access. Altogether, 228 relevant papers were found using the reported search, of which nine represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Following LIV division, the venous drainage takes place via multiple collateral systems such as the azygous/hemiazygous, the internal mammary veins, the lateral thoracic and superficial thoracoabdominal veins, vertebral venous plexus as well as the transverse sinus. The possible complications are mainly left upper limb swelling and neurological symptoms. In one case series of 14 patients, the LIV was divided and ligated to facilitate the exposure for aortic arch surgery. More than 2-year follow-up did not reveal upper limb oedema or neurological symptoms. In two cohorts of 52 patients, the LIV was ligated prior to the superior vena cava (SVC) resection for malignancy. During the mid-term follow-up, no neurological or upper limb symptoms were reported. Although in two studies with 72 and 70 patients undergoing SVC resection it was not specified how many of them had LIV ligation, no relevant complications were reported. In a report, LIV occlusion was observed in 4 patients undergoing left internal jagular vein catheterization for haemodialysis. The reported symptom was left arm swelling with no neurological problems. In a cohort of 18 patients undergoing SVC resection for malignancy and major vein reconstruction, 7 patients underwent ligation of the LIV with no neurological symptoms. It was also concluded that reconstruction of the LIV is not consistent with favourable patency. In a case series of 10 patients with central venous obstruction, collateral pathways

  4. Evaluation of seamless ligation cloning extract preparation methods from an Escherichia coli laboratory strain.

    PubMed

    Okegawa, Yuki; Motohashi, Ken

    2015-10-01

    Seamless ligation cloning extract (SLiCE) is a simple and efficient method for DNA cloning without the use of restriction enzymes. Instead, SLiCE uses homologous recombination activities from Escherichia coli cell lysates. To date, SLiCE preparation has been performed using an expensive commercially available lytic reagent. To expand the utility of the SLiCE method, we evaluated different methods for SLiCE preparation that avoid using this reagent. Consequently, cell extracts prepared with buffers containing Triton X-100, which is a common and low-cost nonionic detergent, exhibited sufficient cloning activity for seamless gene incorporation into a vector.

  5. [Extraperitoneal ligation herniorraphy by the acute infectious diseases of the abdominal cavity in children].

    PubMed

    Ignat'ev, R O; Bataev, S M

    2012-01-01

    Surgery on the reason of the "acute abdomen" in children often reveals the persisting vaginal peritoneal defects, which further lead to hernia formation. 23 children (aged 4-15 years) were operated on the acute uncomplicated appendicitis (n=10), acute mesadenitis (n=3), appendicular local and pelvioperitonitis (n=9) and ovary apoplexia (n=1). Inguinal hernia was revealed in all patients during laparoscopy. After videoendoscopic sanation of the abdomen and appendectomy (if it was necessary) the extraperitoneal ligation herniorraphy in author's modification was performed. The were no cases of abdominal complications as well as hernia recurrence among the treated patients.

  6. Evaluation of the Friction of Self-Ligating and Conventional Bracket Systems

    PubMed Central

    Tecco, Simona; Di Iorio, Donato; Nucera, Riccardo; Di Bisceglie, Beatrice; Cordasco, Giancarlo; Festa, Felice

    2011-01-01

    Objectives: This in vitro study evaluated the friction (F) generated by aligned stainless steel (SS) conventional brackets, self-ligating Damon MX© brackets (SDS Ormco, Glendora, California, USA), Time3© brackets (American Orthodontics, Sheboygan, Wisconsin, USA), Vision LP© brackets (American Orthodontics), and low-friction Slide© ligatures (Leone, Firenze, Italy) coupled with various SS, nickel-titanium (NiTi), and beta-titanium (TMA) archwires. Methods: All brackets had a 0.022-inch slot, and the orthodontic archwires were 0.014-inch, 0.016-inch, 0.014×0.025-inch, 0.018×0.025-inch, and 0.019×0.025-inch NiTi; 0.017×0.025-inch TMA; and 0.019×0.025-inch SS. Each bracket-archwire combination was tested 10 times. In the test, 10 brackets of the same group were mounted in alignment on a metal bar. The archwires moved through all the 10 brackets at a crosshead speed of 0.5 mm/min (each run lasted approximately 5 min). The differences among 5 groups of brackets were analyzed through the Kruskal-Wallis test, and a Mann-Whitney test was calculated as post hoc analysis. The P value was set at 0.05. Results: Coupled with 0.014-inch NiTi and 0.016-inch NiTi, Victory Series© brackets generated the greatest F, while Damon MX© and Vision LP© brackets generated the lowest (P<.05); no significant differences were observed between Time3© brackets and Slide© ligatures. Coupled with all the rectangular archwires, Victory Series© brackets, Slide© ligatures, and Vision LP© self-ligating brackets generated significantly lower F than did Time3© and Damon MX© self-ligating brackets (P<.05). Conclusions: These findings suggest that self-ligating brackets are a family of brackets that, in vitro, can generate different levels of F when coupled with thin or thick, rectangular, or round archwires. Clinical conclusions based on our results are not possible due to the limitations of the experimental conditions. PMID:21769273

  7. CHANGES IN LIPID CONTENT OF SERUM AND OF LIVER FOLLOWING BILATERAL RENAL ABLATION OR URETERAL LIGATION

    PubMed Central

    Winkler, A. W.; Durlacher, S. H.; Hoff, H. E.; Man, E. B.

    1943-01-01

    1. In the dog and monkey bilateral nephrectomy or ureteral ligation results in a marked, progressive increase of total fatty acids, of free and esterified cholesterol, of phospholipid, and of free fat of serum. 2. No such changes follow unilateral nephrectomy, splenectomy, or fasting. 3. The increase after bilateral nephrectomy is not inhibited by glucose administration. 4. A marked increase of the phospholipid and a less significant elevation in cholesterol content of the liver accompanies this increase of serum lipids after bilateral nephrectomy. PMID:19871298

  8. Ligation activity of fragmented ribozymes in frozen solution: implications for the RNA world

    PubMed Central

    Vlassov, Alexander V.; Johnston, Brian H.; Landweber, Laura F.; Kazakov, Sergei A.

    2004-01-01

    A vexing difficulty of the RNA world hypothesis is how RNA molecules of significant complexity could ever have evolved given their susceptibility to degradation. One way degradation might have been reduced is through low temperature. Here we report that truncated and fragmented derivatives of the hairpin ribozyme can catalyze ligation of a wide variety of RNA molecules to a given sequence in frozen solution despite having little or no activity under standard solution conditions. These results suggest that complex RNAs could have evolved in freezing environments on the early earth and perhaps elsewhere. PMID:15161960

  9. Is it safe to divide and ligate the left innominate vein in complex cardiothoracic surgeries?

    PubMed

    McPhee, Arthur; Shaikhrezai, Kasra; Berg, Geoffrey

    2013-09-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether it is safe to divide the left innominate vein (LIV) in aortic arch surgery to improve access. Altogether, 228 relevant papers were found using the reported search, of which nine represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Following LIV division, the venous drainage takes place via multiple collateral systems such as the azygous/hemiazygous, the internal mammary veins, the lateral thoracic and superficial thoracoabdominal veins, vertebral venous plexus as well as the transverse sinus. The possible complications are mainly left upper limb swelling and neurological symptoms. In one case series of 14 patients, the LIV was divided and ligated to facilitate the exposure for aortic arch surgery. More than 2-year follow-up did not reveal upper limb oedema or neurological symptoms. In two cohorts of 52 patients, the LIV was ligated prior to the superior vena cava (SVC) resection for malignancy. During the mid-term follow-up, no neurological or upper limb symptoms were reported. Although in two studies with 72 and 70 patients undergoing SVC resection it was not specified how many of them had LIV ligation, no relevant complications were reported. In a report, LIV occlusion was observed in 4 patients undergoing left internal jagular vein catheterization for haemodialysis. The reported symptom was left arm swelling with no neurological problems. In a cohort of 18 patients undergoing SVC resection for malignancy and major vein reconstruction, 7 patients underwent ligation of the LIV with no neurological symptoms. It was also concluded that reconstruction of the LIV is not consistent with favourable patency. In a case series of 10 patients with central venous obstruction, collateral pathways

  10. Detection of RNA-DNA association by a proximity ligation-based method

    PubMed Central

    Petruk, Svetlana; Fenstermaker, Tyler K.; Black, Kathryn L.; Brock, Hugh W.; Mazo, Alexander

    2016-01-01

    We describe a proximity ligation assay (PLA)-based method of assessing association of DNA and RNA in single cells during the cell cycle. Pulse-labeling of DNA with EdU and RNA with BrU and testing their close proximity by PLA demonstrates that RNA synthesis in individual cells resumes about 30–45 min after DNA replication. Consistent with this conclusion, RNA Pol II phosphorylated at Ser2 of its CTD is detected at the same time as RNA transcripts on nascent DNA. Our results also show that RNA is associated with DNA foci during all stages of mitosis. PMID:27256324

  11. Multiplexed, ligation-dependent probe amplification for rapid and inexpensive HLA-DQB1 allelotyping

    PubMed Central

    Akers, Nicholas K.; Curry, John D.; Smith, Martyn T.; Bracci, Paige M.; Skibola, Christine F.

    2012-01-01

    Many effective options exist to accurately type DNA for HLA alleles. However, most of the existing methods are excessively costly in terms of overall monetary costs, DNA requirements, and proprietary software. We present a novel assay able to resolve heterozygous HLA-DQB1 allelotypes at two digits, with even greater specificity for the HLA-DQB1*06 allele family, by using the multiplexed ligation-dependent probe amplification (MLPA) technology. This assay provides more specific allele data than genome-wide analysis and is more affordable than sequencing, making it a useful intermediate for researchers seeking to accurately allelotype human DNA samples. PMID:21762399

  12. Highly efficient ligation of small RNA molecules for microRNA quantitation by high-throughput sequencing.

    PubMed

    Lee, Jerome E; Yi, Rui

    2014-01-01

    MiRNA cloning and high-throughput sequencing, termed miR-Seq, stands alone as a transcriptome-wide approach to quantify miRNAs with single nucleotide resolution. This technique captures miRNAs by attaching 3' and 5' oligonucleotide adapters to miRNA molecules and allows de novo miRNA discovery. Coupling with powerful next-generation sequencing platforms, miR-Seq has been instrumental in the study of miRNA biology. However, significant biases introduced by oligonucleotide ligation steps have prevented miR-Seq from being employed as an accurate quantitation tool. Previous studies demonstrate that biases in current miR-Seq methods often lead to inaccurate miRNA quantification with errors up to 1,000-fold for some miRNAs. To resolve these biases imparted by RNA ligation, we have developed a small RNA ligation method that results in ligation efficiencies of over 95% for both 3' and 5' ligation steps. Benchmarking this improved library construction method using equimolar or differentially mixed synthetic miRNAs, consistently yields reads numbers with less than two-fold deviation from the expected value. Furthermore, this high-efficiency miR-Seq method permits accurate genome-wide miRNA profiling from in vivo total RNA samples. PMID:25490151

  13. Coated Rectangular Composite Archwires: A Comparison Of Self-Ligating And Conventional Bracket Systems During Sliding Mechanics

    NASA Astrophysics Data System (ADS)

    Woods, David Keith

    The purpose of this study was to analyze the resistance to sliding of coated rectangular fiber reinforced composite archwires using various brackets systems and second-order bracket angulations. Resistance to sliding was investigated for eight bracket systems: six self-ligating brackets (four passive and two passive-active) and two conventional brackets. A rectangular fiber reinforced composite archwire of 0.019 x 0.025-in dimension from BiomersRTM SimpliClear was drawn through a three-bracket model system at ten millimeters per minute for 2.5 millimeters. For each bracket, the resistance to sliding was measured at four bracket angulations (0°, 2.5°, 5°, and 10°) in a dry state at room temperature. The fiber reinforced composite archwire produced the lowest sliding resistance with the passive self-ligating bracket system (Damon DQ) at each bracket angulation tested. Overall, self-ligating bracket systems generated lower sliding resistance than conventionally ligated systems, and one passive/active self-ligating bracket system (In-Ovation-R). There was a significant increase in resistance to sliding as bracket angulation increased for all bracket systems tested. Microscopic analysis revealed increased perforation of the archwire coating material as bracket angulations were increased. Our findings show that the rectangular fiber reinforced composite archwire may be acceptable for sliding mechanics during the intermediate stages of orthodontic tooth movement, however more long-term studies are needed.

  14. Alterations in plaque accumulation and gingival inflammation promoted by treatment with self-ligating and conventional orthodontic brackets

    PubMed Central

    Cardoso, Mauricio de Almeida; Saraiva, Patrícia Pinto; Maltagliati, Liliana Ávila; Rhoden, Fernando Kleinübing; Costa, Carla Cristina Alvarenga; Normando, David; Capelozza, Leopoldino

    2015-01-01

    OBJECTIVE: The aim of the present study was to evaluate, comparatively, the periodontal response during orthodontic treatment performed with self-ligating and conventional brackets. METHODS: Sixteen Caucasian individuals of both sexes, aged between 12 and 16 years old and in permanent dentition were selected. Eight individuals were treated with conventional brackets installed on the lower dental arch and self-ligating brackets on the upper arch. Another eight individuals received self-ligating brackets in the lower arch and conventional brackets in the upper arch. The subjects received material and instructions for oral hygiene. Visible plaque index (VPI), gingival bleeding index (GBI) and clinical attachment level (CAL) were evaluated just after installation of orthodontic appliances, and 30, 60 and 180 days later. Mann-Whitney test was used to compare differences between groups (self-ligating and conventional), two-way ANOVA followed by Tukey's test was used to assess CAL at each site of each tooth. Significance level was set at 5%. RESULTS: No significant changes were found with regard to the assessed parameters (VPI, GBI and CAL) in either one of the systems. CONCLUSION: No significant changes were found with regard to the periodontal response to orthodontic treatment for the variables assessed and between subjects receiving passive self-ligating and conventional brackets. All individuals had received oral hygiene instructions and had their periodontal conditions monitored. PMID:25992985

  15. The effect of dietary consistency and water content on the parotid glands of submandibular and sublingual duct-ligated rats.

    PubMed

    Kurahashi, M

    2002-05-01

    The aim here was to estimate the significance of oral sensation and mastication on functional changes in the parotid glands of partially desalivated rats. Submandibular and sublingual duct-ligated and sham-operated control rats were fed three diets of similar chemical composition but different physical presentations. Two were solid, either pellets or powder, and one was liquid. Water and food intakes were similar for both the duct-ligated rats and sham-operated control rats when they ate the pelleted or powdered-diet, though more food was wasted by the duct-ligated rats in the powdered-diet group than in the pelleted-diet group. No food was wasted in the rats fed the liquid-diet. Parotid gland weight and amylase activity were greatest with the submandibular and sublingual duct-ligated rats fed the powdered-diet and smallest with the duct-ligated and sham-operated control rats fed the liquid-diet. The amount of food wasted correlated positively with the parotid gland weight and parotid amylase activity of the rats. These findings support the view that it is the contact of dry food with the oral mucosa rather than the jaw movements involved in mastication that increases parotid gland weight and amylase activity in partial desalivated rats.

  16. Applications of Convertible Isonitriles in the Ligation and Macrocyclization of Multicomponent Reaction-Derived Peptides and Depsipeptides.

    PubMed

    Wessjohann, Ludger A; Morejón, Micjel C; Ojeda, Gerardo M; Rhoden, Cristiano R B; Rivera, Daniel G

    2016-08-01

    Peptide ligation and macrocyclization are among the most relevant approaches in the field of peptide chemistry. Whereas a variety of strategies relying on coupling reagents and native chemical ligation are available, there is a continuous need for efficient peptide ligation and cyclization methods. Herein we report on the utilization of convertible isonitriles as effective synthetic tools for the ligation and macrocyclization of peptides arising from isocyanide-based multicomponent reactions. The strategy relies on the use of convertible isonitriles-derived from Fukuyama amines-and peptide carboxylic acids in Ugi and Passerini reactions to afford N-alkylated peptides and depsipeptides, respectively, followed by conversion of the C-terminal amide onto either N-peptidoacyl indoles or pyrroles. Such activated peptides proved efficient in the ligation to peptidic, lipidic and fluorescently labeled amines and in macrocyclization protocols. As a result, a wide set of N-substituted peptides (with methyl, glycosyl and amino acids as N-substituents), cyclic N-methylated peptides and a depsipeptide were produced in good yields using conditions that involve either classical heating or microwave irradiation. This report improves the repertoire of peptide covalent modification methods by exploiting the synthetic potential of multicomponent reactions and convertible isonitriles. PMID:27390908

  17. Detection of an Infected N-butyl-2-cyanoacrylate Plug by F-18 FDG PET/CT Scan in a Patient Who Received Endoscopic Intervention for Gastric Variceal Bleeding.

    PubMed

    Joo, Kowoon; Hyun, In Young; Baek, Ji Hyeon; Chung, Moon-Hyun; Lee, Jin-Soo

    2013-06-01

    Injection of N-butyl-2-cyanoacrylate has been used successfully for treatment of gastric variceal bleeding. Bacteremia after injection of N-butyl-2-cyanoacrylate is well known, however, the method for diagnosis of infected endovascular injected material has remained uncertain. This is the first case reporting use of F-18 FDG PET/CT in detection of the source of infection after control of endoscopic bleeding with N-butyl-2-cyanoacrylate.

  18. Electronic Structure of Ligated CdSe Clusters: Dependence on DFT Methodology

    SciTech Connect

    Albert, Victor V.; Ivanov, Sergei A.; Tretiak, Sergei; Kilina, Svetlana V.

    2011-08-18

    Simulations of ligated semiconductor quantum dots (QDs) and their physical properties, such as morphologies, QD–ligand interactions, electronic structures, and optical transitions, are expected to be very sensitive to computational methodology. We utilize Density Functional Theory (DFT) and systematically study how the choice of density functional, atom-localized basis set, and a solvent affects the physical properties of the Cd33Se33 cluster ligated with a trimethylphosphine oxide ligand. We have found that qualitative performance of all exchange-correlation (XC) functionals is relatively similar in predicting strong QD–ligand binding energy (~1 eV). Additionally, all functionals predict shorter Cd–Se bond lengths on the QD surface than in its core, revealing the nature and degree of QD surface reconstruction. For proper modeling of geometries and QD–ligand interactions, however, augmentation of even a moderately sized basis set with polarization functions (e.g., LANL2DZ* and 6-31G*) is very important. A polar solvent has very significant implications for the ligand binding energy, decreasing it to 0.2–0.5 eV. However, the solvent model has a minor effect on the optoelectronic properties, resulting in persistent blue shifts up to ~0.3 eV of the low-energy optical transitions. For obtaining reasonable energy gaps and optical transition energies, hybrid XC functionals augmented by a long-range Hartree–Fock orbital exchange have to be applied.

  19. Controlling tetramer formation, subunit rotation and DNA ligation during Hin-catalyzed DNA inversion

    PubMed Central

    Chang, Yong; Johnson, Reid C.

    2015-01-01

    Two critical steps controlling serine recombinase activity are the remodeling of dimers into the chemically active synaptic tetramer and the regulation of subunit rotation during DNA exchange. We identify a set of hydrophobic residues within the oligomerization helix that controls these steps by the Hin DNA invertase. Phe105 and Met109 insert into hydrophobic pockets within the catalytic domain of the same subunit to stabilize the inactive dimer conformation. These rotate out of the catalytic domain in the dimer and into the subunit rotation interface of the tetramer. About half of residue 105 and 109 substitutions gain the ability to generate stable synaptic tetramers and/or promote DNA chemistry without activation by the Fis/enhancer element. Phe106 replaces Phe105 in the catalytic domain pocket to stabilize the tetramer conformation. Significantly, many of the residue 105 and 109 substitutions support subunit rotation but impair ligation, implying a defect in rotational pausing at the tetrameric conformer poised for ligation. We propose that a ratchet-like surface involving Phe105, Met109 and Leu112 within the rotation interface functions to gate the subunit rotation reaction. Hydrophobic residues are present in analogous positions in other serine recombinases and likely perform similar functions. PMID:26056171

  20. Design and Validation of DNA Libraries for Multiplexing Proximity Ligation Assays

    PubMed Central

    Gobet, Nicolas; Ketterer, Simon; Meier, Matthias

    2014-01-01

    Here, we present an in silico, analytical procedure for designing and testing orthogonal DNA templates for multiplexing of the proximity ligation assay (PLA). PLA is a technology for the detection of protein interactions, post-translational modifications, and protein concentrations. To enable multiplexing of the PLA, the target information of antibodies was encoded within the DNA template of a PLA, where each template comprised four single-stranded DNA molecules. Our DNA design procedure followed the principles of minimizing the free energy of DNA cross-hybridization. To validate the functionality, orthogonality, and efficiency of the constructed template libraries, we developed a high-throughput solid-phase rolling-circle amplification assay and solid-phase PLA on a microfluidic platform. Upon integration on a microfluidic chip, 640 miniaturized pull-down assays for oligonucleotides or antibodies could be performed in parallel together with steps of DNA ligation, isothermal amplification, and detection under controlled microenvironments. From a large computed PLA template library, we randomly selected 10 template sets and tested all DNA combinations for cross-reactivity in the presence and absence of antibodies. By using the microfluidic chip application, we determined rapidly the false-positive rate of the design procedure, which was less than 1%. The combined theoretical and experimental procedure is applicable for high-throughput PLA studies on a microfluidic chip. PMID:25386748

  1. Mechanism of Thiosulfate Oxidation in the SoxA Family of Cysteine-ligated Cytochromes

    PubMed Central

    Grabarczyk, Daniel B.; Chappell, Paul E.; Eisel, Bianca; Johnson, Steven; Lea, Susan M.; Berks, Ben C.

    2015-01-01

    Thiosulfate dehydrogenase (TsdA) catalyzes the oxidation of two thiosulfate molecules to form tetrathionate and is predicted to use an unusual cysteine-ligated heme as the catalytic cofactor. We have determined the structure of Allochromatium vinosum TsdA to a resolution of 1.3 Å. This structure confirms the active site heme ligation, identifies a thiosulfate binding site within the active site cavity, and reveals an electron transfer route from the catalytic heme, through a second heme group to the external electron acceptor. We provide multiple lines of evidence that the catalytic reaction proceeds through the intermediate formation of a S-thiosulfonate derivative of the heme cysteine ligand: the cysteine is reactive and is accessible to electrophilic attack; cysteine S-thiosulfonate is formed by the addition of thiosulfate or following the reverse reaction with tetrathionate; the S-thiosulfonate modification is removed through catalysis; and alkylating the cysteine blocks activity. Active site amino acid residues required for catalysis were identified by mutagenesis and are inferred to also play a role in stabilizing the S-thiosulfonate intermediate. The enzyme SoxAX, which catalyzes the first step in the bacterial Sox thiosulfate oxidation pathway, is homologous to TsdA and can be inferred to use a related catalytic mechanism. PMID:25673696

  2. Comparative study of torque expression among active and passive self-ligating and conventional brackets

    PubMed Central

    Franco, Érika Mendonça Fernandes; Valarelli, Fabrício Pinelli; Fernandes, João Batista; Cançado, Rodrigo Hermont; de Freitas, Karina Maria Salvatore

    2015-01-01

    Abstract Objective: The aim of this study was to compare torque expression in active and passive self-ligating and conventional brackets. Methods: A total of 300 segments of stainless steel wire 0.019 x 0.025-in and six different brands of brackets (Damon 3MX, Portia, In-Ovation R, Bioquick, Roth SLI and Roth Max) were used. Torque moments were measured at 12°, 24°, 36° and 48°, using a wire torsion device associated with a universal testing machine. The data obtained were compared by analysis of variance followed by Tukey test for multiple comparisons. Regression analysis was performed by the least-squares method to generate the mathematical equation of the optimal curve for each brand of bracket. Results: Statistically significant differences were observed in the expression of torque among all evaluated bracket brands in all evaluated torsions (p < 0.05). It was found that Bioquick presented the lowest torque expression in all tested torsions; in contrast, Damon 3MX bracket presented the highest torque expression up to 36° torsion. Conclusions: The connection system between wire/bracket (active, passive self-ligating or conventional with elastic ligature) seems not to interfere in the final torque expression, the latter being probably dependent on the interaction between the wire and the bracket chosen for orthodontic mechanics. PMID:26691972

  3. Binding of Molecular O2 to Di- and Tri-Ligated [U02]+

    SciTech Connect

    G. S. Groenewold; Anita Gianotto

    2006-02-01

    Gas-phase complexes containing dioxouranium(V) cations ([UO2]+) ligated with two or three -donating acetone ligands reacted with dioxygen to form [UO2(A)2,3(O2)]+, where A is acetone. Collision-induced dissociation studies of [UO2(A)3(O2)]+ showed initial loss of acetone, followed by elimination of O2, which suggested that O2 was bound more strongly than the third acetone ligand, but less strongly than the second. Similar behavior was observed for complexes in which water was substituted for acetone. Binding of dioxygen to [UO2]+ containing zero, one, or four ligands did not occur, nor did it occur for analogous ligated U(IV)O2 or U(VI)O2 ions. For example, only addition of acetone and/or H2O occurred for the U(VI) species [UO2OH]+, with the ligand addition cascade terminating in formation of [UO2OH(A)3]+. Similarly, the U(IV) species [UOOH]+ added donor ligands, which produced the mixed-ligand complex [UOOH(A)3(H2O)]+ as the preferred product at the longest reaction times accessible. Since dioxygen normally functions as an electron acceptor, an alternative mode for binding dioxygen to the cationic U(V)O2 center is indicated that is dependent on the presence of an unpaired electron and donor ligands in the uranyl valence orbitals.

  4. Mechanism of thiosulfate oxidation in the SoxA family of cysteine-ligated cytochromes.

    PubMed

    Grabarczyk, Daniel B; Chappell, Paul E; Eisel, Bianca; Johnson, Steven; Lea, Susan M; Berks, Ben C

    2015-04-01

    Thiosulfate dehydrogenase (TsdA) catalyzes the oxidation of two thiosulfate molecules to form tetrathionate and is predicted to use an unusual cysteine-ligated heme as the catalytic cofactor. We have determined the structure of Allochromatium vinosum TsdA to a resolution of 1.3 Å. This structure confirms the active site heme ligation, identifies a thiosulfate binding site within the active site cavity, and reveals an electron transfer route from the catalytic heme, through a second heme group to the external electron acceptor. We provide multiple lines of evidence that the catalytic reaction proceeds through the intermediate formation of a S-thiosulfonate derivative of the heme cysteine ligand: the cysteine is reactive and is accessible to electrophilic attack; cysteine S-thiosulfonate is formed by the addition of thiosulfate or following the reverse reaction with tetrathionate; the S-thiosulfonate modification is removed through catalysis; and alkylating the cysteine blocks activity. Active site amino acid residues required for catalysis were identified by mutagenesis and are inferred to also play a role in stabilizing the S-thiosulfonate intermediate. The enzyme SoxAX, which catalyzes the first step in the bacterial Sox thiosulfate oxidation pathway, is homologous to TsdA and can be inferred to use a related catalytic mechanism.

  5. The effectiveness of Doppler controlled hemorrhoidal artery ligation based on preliminaries results

    PubMed Central

    Yamoul, Rajae; Attolou, Gilles; Njoumi, Noureddine; Alkandry, Siffedine; Tahiri, Moulay El Hassane

    2013-01-01

    In this work, we discuss the preliminary results of the effectiveness of the hemorrhoidal artery ligation under control Doppler as a new technique for the treatment of hemorrhoids. We report the results of patients with hemorrhoids we have followed over a period of one year who were treated with HAL Doppler. The intra-and postoperative complications were monitored. Patient follow-up was established on the immediate postoperative period, after one month, six months and one year of evolution. Monitoring parameters were both objective (prolapse) and subjective (pain, discomfort, bleeding, satisfaction). 120 patients, all stages combined, were treated with HAL Doppler. The pain is easily controlled with painkillers. Residual rectal bleeding was noted in 3% of the cases. In addition, there was one case of recurrent prolapse which underwent reoperation. After one month, 86,5% patients were satisfied. The hemorrhoidal artery ligation under control Doppler is an easy technique, well accepted by patients who are increasingly demanding it. It is less invasive, less painful and gives fewer complications. It is not only effective for stage III and IV hemorrhoids for which the effect is spectacular but also for stages I and II symptoms, which can expand its indications. PMID:24396565

  6. Cost and efficacy comparison of in vitro fertilization and tubal anastomosis for women after tubal ligation

    PubMed Central

    Messinger, Lauren B.; Alford, Connie E.; Csokmay, John M.; Henne, Melinda B.; Mumford, Sunni L.; Segars, James H.; Armstrong, Alicia Y.

    2016-01-01

    Objective To compare cost and efficacy of tubal anastomosis to in vitro fertilization (IVF) in women who desired fertility after a tubal ligation. Design Cost-effectiveness analysis. Setting Not applicable. Patient(s) Not applicable. Intervention(s) Not applicable. Main Outcome Measure(s) Cost per ongoing pregnancy. Result(s) Cost per ongoing pregnancy for women after tubal anastomosis ranged from $16,446 to $223,482 (2014 USD), whereas IVF ranged from $32,902 to $111,679 (2014 USD). Across maternal age groups <35 and 35–40, years tubal anastomosis was more cost effective than IVF for ongoing pregnancy. Sensitivity analyses validated these findings across a wide range of ongoing pregnancy probabilities as well as costs per procedure. Conclusion(s) Tubal anastomosis was the most cost-effective approach for most women less than 41 years of age, whereas IVF was the most cost-effective approach for women aged ≥41 years who desired fertility after tubal ligation. A model was created that can be modified based on cost and success rates in individual clinics for improved patient counseling. PMID:26006734

  7. Use of model peptide reactions for the characterization of kinetically controlled ligation.

    PubMed

    Lee, Joongoo; Kwon, Yoonjin; Pentelute, Brad L; Bang, Duhee

    2011-08-17

    Since the introduction of kinetically controlled ligation (KCL), a chemoselective reaction between a peptide-(α)thioarylester and a Cys-peptide-(α)thioalkylester, KCL has been utilized for the total chemical synthesis of large proteins (i.e., lysozyme and HIV-protease) by providing fully convergent synthetic routes. Although KCL has the potential to become an important chemistry for protein synthesis, the principle of KCL is not fully characterized. In particular, prior work on KCL has focused on the reactivity difference of the two different -(α)thioester forms-alkyl vs aryl. Another equally important feature of KCL, Xaa-Cys ligation sites, has not been investigated. The work reported here describes combinatorial KCL reactions using model peptides to dissect the interplay of the Xaa(1), Xaa(2), -(α)thioarylester, and -(α)thioalkylester. Results from these studies provide fundamental insights into the KCL reaction, and will lead to the optimal synthetic route for the routine chemical synthesis of large target protein molecules.

  8. Rapid synthesis of DNA-cysteine conjugates for expressed protein ligation

    SciTech Connect

    Lovrinovic, Marina; Niemeyer, Christof M. . E-mail: christof.niemeyer@uni-dortmund.de

    2005-09-30

    We report a rapid method for the covalent modification of commercially available amino-modified DNA oligonucleotides with a cysteine moiety. The resulting DNA-cysteine conjugates are versatile reagents for the efficient preparation of covalent DNA-protein conjugates by means of expressed protein ligation (EPL). The EPL method allows for the site-specific coupling of cysteine-modified DNA oligomers with recombinant intein-fusion proteins, the latter of which contain a C-terminal thioester enabling the mild and highly specific reaction with N-terminal cysteine compounds. We prepared a cysteine-modifier reagent in a single-step reaction which allows for the rapid and near quantitative synthesis of cysteine-DNA conjugates. The latter were ligated with the green fluorescent protein mutant EYFP, recombinantly expressed as an intein-fusion protein, allowing for the mild and selective formation of EYFP-DNA conjugates in high yields of about 60%. We anticipate many applications of our approach, ranging from protein microarrays to the arising field of nanobiotechnology.

  9. Evaluating Necessity of Azygos Vein Ligation in Primary Repair of Esophageal Atresia.

    PubMed

    Fathi, Mehdi; Joudi, Marjan; Morteza, Afsaneh

    2015-12-01

    Surgery has dramatically improved survival of infants with esophageal atresia. However, early and late complications of these surgeries affect the future life of this population. A probable step toward minimizing such complications is through modifying the technique of surgery. We evaluated two groups of esophageal atresia undergoing surgery with two different techniques including preservation and ligation of the Azygos vein and compared early complications, duration of surgery, and hospital and neonatal intensive care unit (NICU) stay between them. A total number of 24 patients with mean age of 24 to 48 h, who were diagnosed with esophageal atresia, were included in the study. All cases were randomly allocated in two groups: group A (case group) in which patients underwent surgery with preservation of the Azygos vein and group B (control group) in which patients underwent the former surgical method with ligation of the Azygos vein. Incidence of early complications, duration of surgery, and NICU and hospital stay were compared between the two groups. None of the complications occurred in either group. Duration of surgery, NICU stay, and hospital stay were not statistically significant between the groups. Preserving the Azygos vein during esophageal atresia surgery is probably a good modification of the classic technique. PMID:26730061

  10. Controlling tetramer formation, subunit rotation and DNA ligation during Hin-catalyzed DNA inversion.

    PubMed

    Chang, Yong; Johnson, Reid C

    2015-07-27

    Two critical steps controlling serine recombinase activity are the remodeling of dimers into the chemically active synaptic tetramer and the regulation of subunit rotation during DNA exchange. We identify a set of hydrophobic residues within the oligomerization helix that controls these steps by the Hin DNA invertase. Phe105 and Met109 insert into hydrophobic pockets within the catalytic domain of the same subunit to stabilize the inactive dimer conformation. These rotate out of the catalytic domain in the dimer and into the subunit rotation interface of the tetramer. About half of residue 105 and 109 substitutions gain the ability to generate stable synaptic tetramers and/or promote DNA chemistry without activation by the Fis/enhancer element. Phe106 replaces Phe105 in the catalytic domain pocket to stabilize the tetramer conformation. Significantly, many of the residue 105 and 109 substitutions support subunit rotation but impair ligation, implying a defect in rotational pausing at the tetrameric conformer poised for ligation. We propose that a ratchet-like surface involving Phe105, Met109 and Leu112 within the rotation interface functions to gate the subunit rotation reaction. Hydrophobic residues are present in analogous positions in other serine recombinases and likely perform similar functions.

  11. Electronic Structure of Ligated CdSe Clusters: Dependence on DFT Methodology

    SciTech Connect

    Albert, VV; Ivanov, SA; Tretiak, S; Kilina, SV

    2011-07-07

    Simulations of ligated semiconductor quantum dots (QDs) and their physical properties, such as morphologies, QD-ligand interactions, electronic structures, and optical transitions, are expected to be very sensitive to computational methodology. We utilize Density Functional Theory (DFT) and systematically study how the choice of density functional, atom-localized basis set, and a solvent affects the physical properties of the Cd{sub 33}Se{sub 33} cluster ligated with a trimethyl phosphine oxide ligand. We have found that qualitative performance of all exchange-correlation (XC) functionals is relatively similar in predicting strong QD-ligand binding energy ({approx}1 eV). Additionally, all functionals predict shorter Cd-Se bond lengths on the QD surface than in its core, revealing the nature and degree of QD surface reconstruction. For proper modeling of geometries and QD-ligand interactions, however, augmentation of even a moderately sized basis set with polarization functions (e.g., LANL2DZ* and 6-31G*) is very important. A polar solvent has very significant implications for the ligand binding energy, decreasing it to 0.2-0.5 eV. However, the solvent model has a minor effect on the optoelectronic properties, resulting in persistent blue shifts up to {approx}0.3 eV of the low-energy optical transitions. For obtaining reasonable energy gaps and optical transition energies, hybrid XC functionals augmented by a long-range Hartree-Fock orbital exchange have to be applied.

  12. SpyLigase peptide–peptide ligation polymerizes affibodies to enhance magnetic cancer cell capture

    PubMed Central

    Fierer, Jacob O.; Veggiani, Gianluca; Howarth, Mark

    2014-01-01

    Individual proteins can now often be modified with atomic precision, but there are still major obstacles to connecting proteins into larger assemblies. To direct protein assembly, ideally, peptide tags would be used, providing the minimal perturbation to protein function. However, binding to peptides is generally weak, so assemblies are unstable over time and disassemble with force or harsh conditions. We have recently developed an irreversible protein–peptide interaction (SpyTag/SpyCatcher), based on a protein domain from Streptococcus pyogenes, that locks itself together via spontaneous isopeptide bond formation. Here we develop irreversible peptide–peptide interaction, through redesign of this domain and genetic dissection into three parts: a protein domain termed SpyLigase, which now ligates two peptide tags to each other. All components expressed efficiently in Escherichia coli and peptide tags were reactive at the N terminus, at the C terminus, or at internal sites. Peptide–peptide ligation enabled covalent and site-specific polymerization of affibodies or antibodies against the tumor markers epidermal growth factor receptor (EGFR) and HER2. Magnetic capture of circulating tumor cells (CTCs) is one of the most promising approaches to improve cancer prognosis and management, but CTC capture is limited by inefficient recovery of cells expressing low levels of tumor antigen. SpyLigase-assembled protein polymers made possible the isolation of cancerous cells expressing lower levels of tumor antigen and should have general application in enhancing molecular capture. PMID:24639550

  13. CD28 ligation increases macrophage suppression of T-cell proliferation.

    PubMed

    Silberman, Daniel; Bucknum, Amanda; Bartlett, Thomas; Composto, Gabriella; Kozlowski, Megan; Walker, Amanda; Werda, Amy; Cua, Jackelyn; Sharpe, Arlene H; Somerville, John E; Riggs, James E

    2012-07-01

    When compared to spleen or lymph node cells, resident peritoneal cavity cells respond poorly to T-cell activation in vitro. The greater proportional representation of macrophages in this cell source has been shown to actively suppress the T-cell response. Peritoneal macrophages exhibit an immature phenotype (MHC class II(lo), B7(lo)) that reduces their efficacy as antigen-presenting cells. Furthermore, these cells readily express inducible nitric oxide synthase (iNOS), an enzyme that promotes T-cell tolerance by catabolism of the limiting amino acid arginine. Here, we investigate the ability of exogenous T-cell costimulation to recover the peritoneal T-cell response. We show that CD28 ligation failed to recover the peritoneal T-cell response and actually suppressed responses that had been recovered by inhibiting iNOS. As indicated by cytokine ELISpot and neutralizing monoclonal antibody (mAb) treatment, this 'cosuppression' response was due to CD28 ligation increasing the number of interferon (IFN)-γ-secreting cells. Our results illustrate that cellular composition and cytokine milieu influence T-cell costimulation biology.Cellular & Molecular Immunology advance online publication, 23 April 2012; doi:10.1038/cmi.2012.13.

  14. Glyoxalase-1 overexpression partially prevents diabetes-induced impaired arteriogenesis in a rat hindlimb ligation model.

    PubMed

    Brouwers, Olaf; Yu, Liang; Niessen, Petra; Slenter, Jos; Jaspers, Karolien; Wagenaar, Allard; Post, Mark; Miyata, Toshio; Backes, Walter; Stehouwer, Coen; Huijberts, Maya; Schalkwijk, Casper

    2016-08-01

    We hypothesize that diabetes-induced impaired collateral formation after a hindlimb ligation in rats is in part caused by intracellular glycation and that overexpression of glyoxalase-I (GLO-I), i.e. the major detoxifying enzyme for advanced-glycation-endproduct (AGE) precursors, can prevent this. Wild-type and GLO-I transgenic rats with or without diabetes (induced by 55 mg/kg streptozotocin) were subjected to ligation of the right femoral artery. Laser Doppler perfusion imaging showed a significantly decreased blood perfusion recovery after 6 days in the diabetic animals compared with control animals, without any effect of Glo1 overexpression. In vivo time-of-flight magnetic resonance angiography at 7-Tesla showed a significant decrease in the number and volume of collaterals in the wild-type diabetic animals compared with the control animals. Glo1 overexpression partially prevented this decrease in the diabetic animals. Diabetes-induced impairment of arteriogenic adaptation can be partially rescued by overexpressing of GLO-I, indicating a role of AGEs in diabetes-induced impaired collateral formation.

  15. Prenatal programming of pulmonary hypertension induced by chronic hypoxia or ductal ligation in sheep

    PubMed Central

    2013-01-01

    Abstract Pulmonary hypertension of the newborn is caused by a spectrum of functional and structural abnormalities of the cardiopulmonary circuit. The existence of multiple etiologies and an incomplete understanding of the mechanisms of disease progression have hindered the development of effective therapies. Animal models offer a means of gaining a better understanding of the fundamental basis of the disease. To that effect, a number of experimental animal models are being used to generate pulmonary hypertension in the fetus and newborn. In this review, we compare the mechanisms associated with pulmonary hypertension caused by two such models: in utero ligation of the ductus arteriosus and chronic perinatal hypoxia in sheep fetuses and newborns. In this manner, we make direct comparisons between ductal ligation and chronic hypoxia with respect to the associated mechanisms of disease, since multiple studies have been performed with both models in a single species. We present evidence that the mechanisms associated with pulmonary hypertension are dependent on the type of stress to which the fetus is subjected. Such an analysis allows for a more thorough evaluation of the disease etiology, which can help focus clinical treatments. The final part of the review provides a clinical appraisal of current treatment strategies and lays the foundation for developing individualized therapies that depend on the causative factors. PMID:25006393

  16. Comparison of static friction with self-ligating, modified slot design and conventional brackets

    PubMed Central

    CASTRO, Raquel Morais; SMITH NETO, Perrin; HORTA, Martinho Campolina Rebello; PITHON, Matheus Melo; OLIVEIRA, Dauro Douglas

    2013-01-01

    Objective To compare the static frictional forces generated at the bracket/wire interface of stainless steel brackets with different geometries and angulations, combined with orthodontic wires of different diameters. Material and Methods The frictional forces were evaluated with three different types of metal brackets: a passive self-ligating (SmartClipTM, 3M/Unitek, Monrovia, USA), with a modified slot design (Mini Uni TwinTM, 3M/Unitek, Monrovia, USA) and conventional (Kirium, Abzil, São José do Rio Preto, Brazil). The samples were mounted in a testing device with three different angulations and tested with 0.014" and 0.018" stainless steel wires (American Orthodontics, Sheboygan, USA). The static frictional force was measured using a universal testing machine (DL 500, EMIC®, São José dos Pinhais, Brazil) with a crosshead speed of 1 mm/min. Statistical analysis was performed by two-way ANOVA followed by Bonferroni's post hoc test. Results There was a significant difference (p<0.05) in static friction when the three types of brackets were tested with the same wire size. The wire diameter influenced friction only when the brackets had a 10º angulation (p<0.05). The angulation influenced friction (p<0.05) when the brackets were associated with a 0.018" wire. Conclusion Brackets with a modified slot design showed intermediate static frictional force values between the conventional and self-ligating brackets tested. PMID:24037069

  17. Lcp1 Is a Phosphotransferase Responsible for Ligating Arabinogalactan to Peptidoglycan in Mycobacterium tuberculosis

    PubMed Central

    Harrison, James; Lloyd, Georgina; Joe, Maju; Lowary, Todd L.; Reynolds, Edward; Walters-Morgan, Hannah; Bhatt, Apoorva; Lovering, Andrew; Besra, Gurdyal S.

    2016-01-01

    ABSTRACT Mycobacterium tuberculosis, the etiological agent of tuberculosis (TB), has a unique cell envelope which accounts for its unusual low permeability and contributes to resistance against common antibiotics. The main structural elements of the cell wall consist of a cross-linked network of peptidoglycan (PG) in which some of the muramic acid residues are covalently attached to a complex polysaccharide, arabinogalactan (AG), via a unique α-l-rhamnopyranose–(1→3)-α-d-GlcNAc-(1→P) linker unit. While the molecular genetics associated with PG and AG biosynthetic pathways have been largely delineated, the mechanism by which these two major pathways converge has remained elusive. In Gram-positive organisms, the LytR-CpsA-Psr (LCP) family of proteins are responsible for ligating cell wall teichoic acids to peptidoglycan, through a linker unit that bears a striking resemblance to that found in mycobacterial arabinogalactan. In this study, we have identified Rv3267 as a mycobacterial LCP homolog gene that encodes a phosphotransferase which we have named Lcp1. We demonstrate that lcp1 is an essential gene required for cell viability and show that recombinant Lcp1 is capable of ligating AG to PG in a cell-free radiolabeling assay. PMID:27486192

  18. A N3S(thioether)-Ligated CuII-Superoxo with Enhanced Reactivity

    PubMed Central

    Kim, Sunghee; Lee, Jung Yoon; Cowley, Ryan E.; Ginsbach, Jake W.; Siegler, Maxime A.; Solomon, Edward I.; Karlin, Kenneth D.

    2015-01-01

    Previous efforts to synthesize a cupric superoxide complex possessing a thioether donor have resulted in the formation of an end-on trans-peroxodicopper(II) species, [{(Ligand)CuII}2(μ-1,2-O22−)]2+. Redesign/modification of previous N3S tetradentate ligands has now allowed for the stabilization of the monomeric, superoxide product possessing a S(thioether)-ligation, [(DMAN3S)CuII(O2•−)]+ (2S), as characterized by UV-vis and resonance Raman (rR) spectroscopies. This complex mimics the putative CuII(O2•−) active species of the copper monooxygenase PHM and exhibits enhanced reactivity towards both O-H and C-H substrates in comparison to close analogues [(L)CuII(O2•−)]+, where L contains only nitrogen donor atoms. Cu-S(thioether) ligation with its weaker donor ability (relative to an N-donor) are demonstrated by comparisons to the chemistry of analogue compounds. PMID:25697226

  19. Pathogen detection in milk samples by ligation detection reaction-mediated universal array method.

    PubMed

    Cremonesi, P; Pisoni, G; Severgnini, M; Consolandi, C; Moroni, P; Raschetti, M; Castiglioni, B

    2009-07-01

    This paper describes a new DNA chip, based on the use of a ligation detection reaction coupled to a universal array, developed to detect and analyze, directly from milk samples, microbial pathogens known to cause bovine, ovine, and caprine mastitis or to be responsible for foodborne intoxication or infection, or both. Probes were designed for the identification of 15 different bacterial groups: Staphylococcus aureus, Streptococcus agalactiae, nonaureus staphylococci, Streptococcus bovis, Streptococcus equi, Streptococcus canis, Streptococcus dysgalactiae, Streptococcus parauberis, Streptococcus uberis, Streptococcus pyogenes, Mycoplasma spp., Salmonella spp., Bacillus spp., Campylobacter spp., and Escherichia coli and related species. These groups were identified based on the 16S rRNA gene. For microarray validation, 22 strains from the American Type Culture Collection or other culture collections and 50 milk samples were tested. The results demonstrated high specificity, with sensitivity as low as 6 fmol. Moreover, the ligation detection reaction-universal array assay allowed for the identification of Mycoplasma spp. in a few hours, avoiding the long incubation times of traditional microbiological identification methods. The universal array described here is a versatile tool able to identify milk pathogens efficiently and rapidly. PMID:19528580

  20. Ligation of Glycophorin A Generates Reactive Oxygen Species Leading to Decreased Red Blood Cell Function

    PubMed Central

    Khoory, Joseph; Estanislau, Jessica; Elkhal, Abdallah; Lazaar, Asmae; Melhorn, Mark I.; Brodsky, Abigail; Illigens, Ben; Hamachi, Itaru; Kurishita, Yasutaka; Ivanov, Alexander R.; Shevkoplyas, Sergey; Shapiro, Nathan I.; Ghiran, Ionita C.

    2016-01-01

    Acute, inflammatory conditions associated with dysregulated complement activation are characterized by significant increases in blood concentration of reactive oxygen species (ROS) and ATP. The mechanisms by which these molecules arise are not fully understood. In this study, using luminometric- and fluorescence-based methods, we show that ligation of glycophorin A (GPA) on human red blood cells (RBCs) results in a 2.1-fold, NADPH-oxidase-dependent increase in intracellular ROS that, in turn, trigger multiple downstream cascades leading to caspase-3 activation, ATP release, and increased band 3 phosphorylation. Functionally, using 2D microchannels to assess membrane deformability, GPS-ligated RBCs travel 33% slower than control RBCs, and lipid mobility was hindered by 10% using fluorescence recovery after photobleaching (FRAP). These outcomes were preventable by pretreating RBCs with cell-permeable ROS scavenger glutathione monoethyl ester (GSH-ME). Our results obtained in vitro using anti-GPA antibodies were validated using complement-altered RBCs isolated from control and septic patients. Our results suggest that during inflammatory conditions, circulating RBCs significantly contribute to capillary flow dysfunctions, and constitute an important but overlooked source of intravascular ROS and ATP, both critical mediators responsible for endothelial cell activation, microcirculation impairment, platelet activation, as well as long-term dysregulated adaptive and innate immune responses. PMID:26784696

  1. Complete mesocolic excision and central vascular ligation for colon cancer: Principle, anatomy, surgical technique, and outcomes.

    PubMed

    Kim, Nam Kyu; Kim, Young Wan; Han, Yoon Dae; Cho, Min Soo; Hur, Hyuk; Min, Byung Soh; Lee, Kang Young

    2016-09-01

    Classic colon cancer surgery refers to a wide resection of the tumor-bearing segment and the lymphatics draining along the named artery. The concept of TME has been applied to colon cancer and complete mesocolic excision (CME) in conjuction with central vascular ligation (CVL) has been introduced as the surgical treatment for colon cancer. Here, we discuss appropriate CME procedure with regard to the oncologic backgrounds, essential components, applied anatomy, laparoscopic technique, short-term, and oncologic outcomes. The introduction of CME has improved oncologic outcomes greatly in patients with colon cancer. The improved outcomes with CME can be attributed to underlying sound oncologic principles such as dissection through the proper plane of mesocolic excision, central vascular ligation, and sufficient length of proximal and distal margins. Thereby, CME technique can achieve en bloc removal of the diseased lesion with the increased amount of the colonic mesentery even though the length of for both bowel and mesentery resection remains a matter of debate. CME is a technically demanding operation thus, comprehensive understanding of the applied vascular anatomy is essential for successful CME. Favorable outcomes of open CME have been replicated with a laparoscopic approach. In future perspective, incorporating a structured education program on minimally invasive (laparoscopy or robot) CME would be beneficial. PMID:27566031

  2. Electrochemical detection of aqueous Ag+ based on Ag+-assisted ligation reaction

    PubMed Central

    Miao, Peng; Han, Kun; Wang, Bidou; Luo, Gangyin; Wang, Peng; Chen, Mingli; Tang, Yuguo

    2015-01-01

    In this work, a novel strategy to fabricate a highly sensitive and selective biosensor for the detection of Ag+ is proposed. Two DNA probes are designed and modified on a gold electrode surface by gold-sulfur chemistry and hybridization. In the presence of Ag+, cytosine-Ag+-cytosine composite forms and facilitates the ligation event on the electrode surface, which can block the release of electrochemical signals labeled on one of the two DNA probes during denaturation process. Ag+ can be sensitively detected with the detection limit of 0.1 nM, which is much lower than the toxicity level defined by U.S. Environmental Protection Agency. This biosensor can easily distinguish Ag+ from other interfering ions and the performances in real water samples are also satisfactory. Moreover, the two DNA probes are designed to contain the recognition sequences of a nicking endonuclease, and the ligated DNA can thus be cleaved at the original site. Therefore, the electrode can be regenerated, which allows the biosensor to be reused for additional tests. PMID:25779347

  3. Controlling tetramer formation, subunit rotation and DNA ligation during Hin-catalyzed DNA inversion.

    PubMed

    Chang, Yong; Johnson, Reid C

    2015-07-27

    Two critical steps controlling serine recombinase activity are the remodeling of dimers into the chemically active synaptic tetramer and the regulation of subunit rotation during DNA exchange. We identify a set of hydrophobic residues within the oligomerization helix that controls these steps by the Hin DNA invertase. Phe105 and Met109 insert into hydrophobic pockets within the catalytic domain of the same subunit to stabilize the inactive dimer conformation. These rotate out of the catalytic domain in the dimer and into the subunit rotation interface of the tetramer. About half of residue 105 and 109 substitutions gain the ability to generate stable synaptic tetramers and/or promote DNA chemistry without activation by the Fis/enhancer element. Phe106 replaces Phe105 in the catalytic domain pocket to stabilize the tetramer conformation. Significantly, many of the residue 105 and 109 substitutions support subunit rotation but impair ligation, implying a defect in rotational pausing at the tetrameric conformer poised for ligation. We propose that a ratchet-like surface involving Phe105, Met109 and Leu112 within the rotation interface functions to gate the subunit rotation reaction. Hydrophobic residues are present in analogous positions in other serine recombinases and likely perform similar functions. PMID:26056171

  4. Synthesis of l- and d-Ubiquitin by One-Pot Ligation and Metal-Free Desulfurization.

    PubMed

    Huang, Yi-Chao; Chen, Chen-Chen; Gao, Shuai; Wang, Ye-Hai; Xiao, Hua; Wang, Feng; Tian, Chang-Lin; Li, Yi-Ming

    2016-05-23

    Native chemical ligation combined with desulfurization has become a powerful strategy for the chemical synthesis of proteins. Here we describe the use of a new thiol additive, methyl thioglycolate, to accomplish one-pot native chemical ligation and metal-free desulfurization for chemical protein synthesis. This one-pot strategy was used to prepare ubiquitin from two or three peptide segments. Circular dichroism spectroscopy and racemic protein X-ray crystallography confirmed the correct folding of ubiquitin. Our results demonstrate that proteins synthesized chemically by streamlined 9-fluorenylmethoxycarbonyl (Fmoc) solid-phase peptide synthesis coupled with a one-pot ligation-desulfurization strategy can supply useful molecules with sufficient purity for crystallographic studies.

  5. Comparative evaluation of efficacy of self-ligating interactive bracket with conventional preadjusted bracket: A clinical study

    PubMed Central

    Jayachandran, Balajee; Padmanabhan, Ratna; Vijayalakshmi, Devaki; Padmanabhan, Janardhanam

    2016-01-01

    Aims and Objectives: This clinical study was conducted to compare the interactive self-ligating twin brackets and the standard double width brackets for their efficiency in Rate of Retraction. Materials and Methods: A total of 20 patients with Angle's class I or class II or class III dento-alveolar malocclusions between the age group of 18-25 years were selected. 10 patients in each group both males and females were randomly selected for the study. Ten patients were bonded using conventional brackets (Group I) the other ten patients were bonded using Interactive self-ligating brackets (Group II). The Rate of retraction was quantified using the scanned models. Pretreatment and post treatment models were taken and scanned to measure the amount of Incisor movement and Anchor loss. Results: (1) Interactive Self-ligating brackets showed significant Rate of retraction when compared with conventional brackets on right and left quadrant. (Group I 0.545 ± .205: Group II 0.827 ± .208 P = .013*) (Group I 0.598 ± .160: Group II 0.804 ± .268 P = .071) (2) Interactive self-ligating brackets when compared with conventional brackets had significant amount of incisor movement on right and left quadrant. (Group I 3.51 ± .548: Group II 4.38 ± .1.06 P = .047*) and (Group I 3.66 ± .899: Group II 4.67 ± 1.02 P = .047*) (3) Conventional brackets showed significant Amount of Anchor loss when compared with that of Interactive self-ligating brackets on right and left quadrant. (Group I .948 ± .392: Group II 0.501 ± .229 P = .013*). In the left side (Group I 0.861 ± .464: Group II 0.498 ± .227 P = .060). Conclusion: The interactive self-ligating brackets show more efficiency in Rate of Retraction, Amount of Incisor movement and Amount of Anchor loss when compared with the conventional brackets. PMID:27307660

  6. Application of meta- and para- phenylenediamine as enhanced oxime ligation catalysts for protein labeling, PEGylation, immobilization and release

    PubMed Central

    Mahmoodi, Mohammad M.; Rashidian, Mohammad; Zhang, Yi; Distefano, Mark D.

    2015-01-01

    Meta- and para- phenylenediamines have recently been shown to catalyze oxime and hydrazone ligation reactions at rates much faster than aniline, a commonly used catalyst. Here, it is demonstrated how these new catalysts can be used in a generally applicable procedure for fluorescent labeling, PEGylation, immobilization and release of aldehyde and ketone functionalized proteins. The chemical orthogonality of phenylenediamine-catalyzed oxime ligation versus copper catalyzed click reaction has also been harnessed for simultaneous dual labeling of bifunctional proteins containing both aldehyde and alkyne groups in high yield. PMID:25640893

  7. Toward Homogeneous Erythropoietin: Chemical Synthesis of the Ala1-Gly28 Glycopeptide Domain by “Alanine” Ligation

    PubMed Central

    Kan, Cindy; Trzupek, John D.; Wu, Bin; Wan, Qian; Chen, Gong; Tan, Zhongping; Yuan, Yu; Danishefsky, Samuel J.

    2009-01-01

    The Ala1—Gly28 glycopeptide fragment (28) of EPO was prepared by chemical synthesis as a single glycoform. Key steps in the synthesis include attachment of a complex dodecasaccharide (7) to a seven amino acid peptide via Lansbury aspartylation, native chemical ligation to join peptide 19 with the glycopeptide domain 18, and a selective desulfurization at the ligation site to reveal the natural Ala19. This glycopeptide fragment (28) contains both the requisite N-linked dodecasaccharide and a C-terminal αthioester handle, the latter feature permitting direct coupling with a glycopeptide fragment bearing N-terminal Cys29 without further functionalization. PMID:19334679

  8. The Safety and Efficacy of Gastric Fundal Variceal Obliteration Using N-Butyl-2-Cyanoacrylate; The Experience of a Single Canadian Tertiary Care Centre

    PubMed Central

    Mosli, Mahmoud H.; Aljudaibi, Bandar; Almadi, Majid; Marotta, Paul

    2013-01-01

    Background/Aim: Bleeding from Gastric Varices (GV) is not only life threatening, but also leads to many hospitalizations, contributes to morbidity and is resource intensive. GV are difficult to diagnose and their treatment can be challenging due to their location and complex structure. To assess the safety and efficacy of endoscopic gastric fundal variceal gluing using periodic endoscopic injections of N-butyl-2-cyanoacylate (NBCA) and to assess the utility of endoscopic ultrasound (EUS) in assessing for the eradication of GV post-NBCA treatment. Materials and Methods: Analysis of prospectively collected data of a cohort of patients with GV who underwent periodic endoscopic variceal gluing from 2005 to 2011. Outcomes included success of GV obliteration, incidence of rebleeding, complications from the procedure, and analysis of factors that might predict GV rebleeding. The success of GV eradication was assessed by both EUS and direct endoscopy. Results: The cohort consisted of 29 consecutive patients that had undergone NBCA injection for GV. The mean age was 60.8 years standard deviations (SD 13.3, range 20-81). The average follow-up was 28 months (SD 19.61, range 1-64) and the most common cause for GV was alcoholic liver cirrhosis (34.48%). A total of 91 sessions of NBCA injections were carried out for 29 patients (average of 3.14 sessions/patient, SD 1.79, range 1-8) with a total of 124 injections applied (average of 4.28 injections/patient, SD 3.09, range 1-13). 24 patients were treated for previously documented GV bleeding while five were treated for primary prevention. Overall, 79% of patients were free of rebleeding once three sessions of histoacryl® injection were completed. None of the patients treated for primary prevention developed bleeding during follow-up. 11 of the 24 patients (46%) with previous bleeding however had rebleeding. 4/11 (36%) patients had GV rebleeding while awaiting scheduled additional NBCA sessions. 19/29 (60%) patients had complete

  9. Increased secretion of insulin and proliferation of islet {beta}-cells in rats with mesenteric lymph duct ligation

    SciTech Connect

    Nagino, Ko; Yokozawa, Junji; Sasaki, Yu; Matsuda, Akiko; Takeda, Hiroaki; Kawata, Sumio

    2012-08-24

    Highlights: Black-Right-Pointing-Pointer Insulin secretion was increased during the OGTT or IVGTT in mesenteric lymph duct-ligated rats. Black-Right-Pointing-Pointer Proliferation of islet {beta}-cells was upregulated in lymph duct-ligated rats. Black-Right-Pointing-Pointer Mesenteric lymph duct flow has a role in glucose metabolism. -- Abstract: Background and aims: It has been suggested that intestinal lymph flow plays an important role in insulin secretion and glucose metabolism after meals. In this study, we investigated the influence of ligation of the mesenteric lymph duct on glucose metabolism and islet {beta}-cells in rats. Methods: Male Sprague-Dawley rats (10 weeks old) were divided into two groups: one underwent ligation of the mesenteric lymph duct above the cistern (ligation group), and the other underwent a sham operation (sham group). After 1 and 2 weeks, fasting plasma concentrations of glucose, insulin, triglyceride, glucose-dependent insulinotropic polypeptide (GIP), and the active form of glucagon-like peptide-1 (GLP-1) were measured. At 2 weeks after the operation, the oral glucose tolerance test (OGTT) and intravenous glucose tolerance test (IVGTT) were performed. After the rats had been sacrificed, the insulin content of the pancreas was measured and the proliferation of {beta}-cells was assessed immunohistochemically using antibodies against insulin and Ki-67. Results: During the OGTT, the ligation group showed a significant decrease in the plasma glucose concentration at 120 min (p < 0.05) and a significant increase in the plasma insulin concentration by more than 2-fold at 15 min (p < 0.01). On the other hand, the plasma GIP concentration was significantly decreased at 60 min (p < 0.01) in the ligated group, while the active form of GLP-1 showed a significantly higher level at 90 min (1.7-fold; p < 0.05) and 120 min (2.5-fold; p < 0.01). During the IVGTT, the plasma insulin concentration in the ligation group was significantly higher at 2

  10. Management of Bleeding Duodenal Varices with Combined TIPS Decompression and Trans-TIPS Transvenous Obliteration Utilizing 3% Sodium Tetradecyl Sulfate Foam Sclerosis

    PubMed Central

    Saad, Wael E; Lippert, Allison; Schwaner, Sandra; Al-Osaimi, Abdullah; Sabri, Saher; Saad, Nael

    2014-01-01

    Objectives: Endoscopic experience in the management of duodenal varices (DVs) is limited and challenging given the anatomic constraints and limited experience. The endovascular management of DVs is not yet established and the controversy of whether to manage them by decompression with a transjugular intrahepatic portosystemic shunt (TIPS) or by transvenous obliteration is unresolved. In the literature, the 6–12 month rebleeding rate of DVs after TIPS is 21-37% and after transvenous obliteration is 13%. The purpose of the study is to evaluate the clinical outcome of combined TIPS decompression and transvenous obliteration/sclerosis. Materials and Methods: This is a retrospective study (case series) of two institutions, evaluating patients who underwent TIPS and/or transvenous obliteration/sclerosis for bleeding DVs (from January 2009 to June 2013). TIPS was performed according to a standard procedure using covered stents. Transvenous obliteration (variceal sclerosis) from the systemic and/or portal venous circulation was performed utilizing 3% sodium tetradecyl sulfate foam. Transvenous obliteration was commonly augmented with coils and/or vascular plugs. Technical (technical success of establishing TIPS and completely obliterating the DVs) and clinical outcomes (rebleeding rate and survival) were evaluated. Results: Five patients with liver cirrhosis presenting with bleeding DVs were included in the study with all eventually (and coincidentally) receiving TIPS and transvenous obliteration. Two of the five patients underwent concomitant TIPS and transvenous obliteration in the same procedural setting. However, three patients underwent transvenous obliteration due to bleeding despite a patent TIPS that had been previously placed. The average time from TIPS placement to transvenous obliteration was 125 days (range: 3-324 days). After having both procedures, there was no rebleeding in the patients during a mean follow-up period of 22 months (6–50 months). Coils and

  11. Cationic Gold Clusters Ligated with Differently Substituted Phosphines: Effect of Substitution on Ligand Reactivity and Binding

    SciTech Connect

    Johnson, Grant E.; Olivares, Astrid M.; Hill, David E.; Laskin, Julia

    2015-01-01

    We present a systematic study of the effect of the number of methyl (Me) and cyclohexyl (Cy) functional groups in monodentate phosphine ligands on the solution-phase synthesis of ligated sub-nanometer gold clusters and their gas-phase fragmentation pathways. Small mixed ligand cationic gold clusters were synthesized using ligand exchange reactions between pre-formed triphenylphosphine ligated (PPh3) gold clusters and monodentate Me- and Cy-substituted ligands in solution and characterized using electrospray ionization mass spectrometry (ESI-MS) and collision-induced dissociation (CID) experiments. Under the same experimental conditions, larger gold-PPh3 clusters undergo efficient exchange of unsubstituted PPh3 ligands for singly Me- and Cy-substituted PPh2Me and PPh2Cy ligands. The efficiency of ligand exchange decreases with an increasing number of Me or Cy groups in the substituted phosphine ligands. CID experiments performed for a series of ligand-exchanged gold clusters indicate that loss of a neutral Me-substituted ligand is preferred over loss of a neutral PPh¬3 ligand while the opposite trend is observed for Cy-substituted ligands. The branching ratio of the competing ligand loss channels is strongly correlated with the electron donating ability of the phosphorous lone pair as determined by the relative proton affinity of the ligand. The results indicate that the relative ligand binding energies increase in the order PMe3 < PPhMe2 < PPh2Me < PPh3< PPh2Cy < PPhCy2< PCy3. Furthermore, the difference in relative ligand binding energies increases with the number of substituted PPh3-mMem or PPh3-mCym ligands (L) exchanged onto each cluster. This study provides the first experimental determination of the relative binding energies of ligated gold clusters containing differently substituted monophosphine ligands, which are important to controlling their synthesis and reactivity in solution. The results also indicate that ligand substitution is an important

  12. Comparison of Frictional Forces Generated by a New Ceramic Bracket with the Conventional Brackets using Unconventional and Conventional Ligation System and the Self-ligating Brackets: An In Vitro Study

    PubMed Central

    Pasha, Azam; Vishwakarma, Swati; Narayan, Anjali; Vinay, K; Shetty, Smitha V; Roy, Partha Pratim

    2015-01-01

    Background: Fixed orthodontic mechanotherapy is associated with friction between the bracket - wire - ligature interfaces during the sliding mechanics. A sound knowledge of the various factors affecting the magnitude of friction is of paramount importance. The present study was done to analyze and compare the frictional forces generated by a new ceramic (Clarity Advanced) bracket with the conventional, (metal and ceramic) brackets using unconventional and conventional ligation system, and the self-ligating (metal and ceramic) brackets in the dry condition. Materials and Methods: The various bracket wire ligation combinations were tested in dry condition. The brackets used were of 0.022″ × 0.028″ nominal slot dimension of MBT prescription: Stainless steel (SS) self-ligating bracket (SLB) of (SmartClip), SS Conventional bracket (CB) (Victory series), Ceramic SLB (Clarity SL), Conventional Ceramic bracket with metal slot (Clarity Bracket), Clarity Advanced Ceramic Brackets (Clarity™ ADVANCED, 3M Unitek). These brackets were used with two types of elastomeric ligatures: Conventional Elastomeric Ligatures (CEL) (Clear medium mini modules) and Unconventional Elastomeric Ligatures (UEL) (Clear medium slide ligatures, Leone orthodontic products). The aligning and the retraction wires were used, i.e., 0.014″ nickel titanium (NiTi) wires and 0.019″ × 0.025″ SS wires, respectively. A universal strength testing machine was used to measure the friction produced between the different bracket, archwires, and ligation combination. This was done with the use of a custom-made jig being in position. Results: Mean, standard deviation, and range were computed for the frictional values obtained. Results were subjected to statistical analysis through ANOVA. The frictional resistance observed in the new Clarity Advanced bracket with a conventional elastomeric ligature was almost similar with the Clarity metal slot bracket with a conventional elastomeric ligature. When using

  13. A comparison of the forces required to produce tooth movement in vitro using two self-ligating brackets and a pre-adjusted bracket employing two types of ligation.

    PubMed

    Sims, A P; Waters, N E; Birnie, D J; Pethybridge, R J

    1993-10-01

    Friction in fixed appliance systems has received considerable attention in the recent literature, although that attributable to the type of ligation used has not been fully investigated. This in vitro study of 0.022 x 0.028 inch slot Minitwin, Activa ('A' Company, San Diego, California, USA), and SPEED brackets (Strite Industries Ltd., Cambridge, Ontario, Canada), investigates friction in two forms of self-ligating brackets and in two methods of ligating Minitwin straight wire brackets with polyurethane elastomeric ligatures. The resistance to sliding of rectangular archwires through the ligated brackets was measured on a vertically mounted Instron testing machine. The stainless steel archwires used were straight lengths of 0.016" x 0.022", 0.017" x 0.025", 0.018" x 0.025", and 0.019" x 0.025" Nubryte Gold (GAC International Inc., Central Islip, New York, USA). The results showed a significant reduction (P < 0.01) in frictional resistance in the Activa brackets compared with SPEED brackets by a factor of approximately 15. When the SPEED brackets were compared to Minitwin brackets, the reduction in friction was by 50-70 per cent (P < 0.01). The placing of 'figure-of-eight' elastomeric ties increased friction by a factor of 70-220 per cent compared to conventional elastomeric ties (P < 0.01) except for 0.016" x 0.022" archwires. The results indicate that self-ligating brackets require less force to produce tooth movement because they apply less frictional contact to the archwire than conventionally tied siamese brackets. PMID:8223972

  14. [Family planning and tubal ligation: analysis of the work of a team of health providers].

    PubMed

    Marcolino, Clarice

    2004-01-01

    This article presents partial results from a study aimed at recognizing the work of members of a public health team who regularly perform tubal ligations. Empirical data were obtained through interviews and observation of routine activities by nine team members. The principal analytical categories were health work concepts. The team was basically characterized as hierarchical, but the specific decision on surgical sterilization tended to become more horizontal, with a tendency towards a multidisciplinary approach. This situation tends to involve the ethical dimension, with a shift from scientific and biomedical knowledge to the social sciences and humanities. On the other hand, and in a contradictory way, in the actual decision to perform surgical sterilization, technical criteria are supported by biomedical knowledge, and comprehensive knowledge is relegated to a secondary role.

  15. Incorporation of azides into recombinant proteins for chemoselective modification by the Staudinger ligation.

    PubMed

    Kiick, Kristi L; Saxon, Eliana; Tirrell, David A; Bertozzi, Carolyn R

    2002-01-01

    The introduction of chemically unique groups into proteins by means of non-natural amino acids has numerous applications in protein engineering and functional studies. One method to achieve this involves the utilization of a non-natural amino acid by the cell's native translational apparatus. Here we demonstrate that a methionine surrogate, azidohomoalanine, is activated by the methionyl-tRNA synthetase of Escherichia coli and replaces methionine in proteins expressed in methionine-depleted bacterial cultures. We further show that proteins containing azidohomoalanine can be selectively modified in the presence of other cellular proteins by means of Staudinger ligation with triarylphosphine reagents. Incorporation of azide-functionalized amino acids into proteins in vivo provides opportunities for protein modification under native conditions and selective labeling of proteins in the intracellular environment. PMID:11752401

  16. Partial embolization as re-treatment of hypersplenism after unsuccessful splenic artery ligation

    PubMed Central

    Xu, Zheng-Ju; Zheng, Lian-Qiu; Pan, Xing-Nan

    2015-01-01

    Ligation of splenic artery (LSA) is used for the treatment of liver cirrhosis with hypersplenism. However, hypersplenism is not significantly improved following LSA treatment in some cases, and there are few reports of retreatment of hypersplenism after LSA. We report the case of a 47-year-old man with liver cirrhosis and hypersplenism who underwent LSA treatment, but did not significantly improve. Laboratory tests revealed severe leukocytopenia and thrombocytopenia. Celiac computed tomography arteriogram and digital subtraction angiography revealed two compensatory arteries connected to the hilar splenic artery from the left gastro-epiploic artery and from the dorsal pancreatic artery. Partial splenic embolization (PSE) was performed through the compensatory arteries. As a result, the patient achieved partial splenic ischemic infarction, and white blood cell and platelet counts rose and remained in the normal range. PSE is an effective therapeutic modality for the retreatment of hypersplenism when other modalities have failed. PMID:25632215

  17. Cerebral Thromboembolism From Ligated Blalock-Taussig Shunt in an Adult Patient.

    PubMed

    Mykychak, Yaroslav B; Bohuta, Lyubomyr Y; Ivanov, Yaroslav Y; Pozniak, Yulia V; Khanenova, Valentyna A; Babliak, Oleksandr D; Yemets, Illya M

    2016-01-01

    A 26-year-old woman underwent tetralogy of Fallot repair and classic Blalock-Taussig shunt (BTS) ligation. On postoperative day 4 she developed severe left-sided hemiplegia due to cerebral infarction. Thrombi in the BTS stump, right brachiocephalic artery, and its branches were removed surgically and the BTS stump was resected. The patient gradually recovered from hemiplegia and is leading a normal life with moderate left hemiparesis and is in good functional status 4 years after the event. An aggressive approach in treating this complication was crucial to prevent further thrombosis and neurologic deficit progression in this patient. We recommend reducing the size of the BTS stump during definitive repair. PMID:26694281

  18. Laser brackets debonding: Tm:YAP and ClarityTM SL self-ligating appliance system

    NASA Astrophysics Data System (ADS)

    Dostálová, Tatjana; Jelínková, Helena; Šulc, Jan; Koranda, Petr; Němec, Michal; Jelínek, Michal; Fibrich, Martin; Michalik, Pavel; Miyagi, Mitsunobu

    2010-02-01

    The study demonstrates the possibility of using Tm:YAP laser radiation for the removing ceramic brackets. The amount of enamel loss and residual resin on teeth has been evaluated. A diode-pumped Tm:YAP microchip laser generating at wavelength 1.9 μm was used for the debonding process. The transmission and absorption measurement of the basic elements - bracket, adhesive resin, and enamel was analyzed to explain the source of the heat and bracket debonding. Quantitative measurements are made for visualizing enamel surface before and after a self-ligating bonding technique. Temperature rise observation during the debonding procedure - from 0.5 to 2 W power - has improved the accuracy of assessment. The results were evaluated by CCD camera and scanning electron microscope. From the measurements it is possible to conclude that continuously running small diode pumped Tm:YAP microchip laser having output power 1W can remove the ceramic bracket without enamel iatrogenic damage.

  19. Rapid ligations with equimolar reactants in water with the potassium acyltrifluoroborate (KAT) amide formation.

    PubMed

    Noda, Hidetoshi; Erős, Gábor; Bode, Jeffrey W

    2014-04-16

    The identification of fast, chemoselective bond-forming reactions is one of the major contemporary challenges in chemistry. We show that chemoselective amide-forming ligations of potassium acyltrifluoroborates (KATs) and O-carbamoylhydroxylamines proceed in the presence of all unprotected functional groups with a second-order rate constant of 20 M(-1) s(-1). PEG chains, lipids, biotin, and dyes were introduced onto an unprotected 31-mer peptide (a GLP-1 analogue) with equimolar ratios of reactants within minutes at 1 mM and within 1 h at 100 μM, even with Mw 20,000 PEG. This conjugation reaction provides a new approach to the synthesis of molecules such as protein-protein and protein-polymer conjugates. PMID:24684235

  20. Catalytic dehydroaromatization of n-alkanes by pincer-ligated iridium complexes

    NASA Astrophysics Data System (ADS)

    Ahuja, Ritu; Punji, Benudhar; Findlater, Michael; Supplee, Carolyn; Schinski, William; Brookhart, Maurice; Goldman, Alan S.

    2011-02-01

    Aromatic hydrocarbons are among the most important building blocks in the chemical industry. Benzene, toluene and xylenes are obtained from the high temperature thermolysis of alkanes. Higher alkylaromatics are generally derived from arene-olefin coupling, which gives branched products—that is, secondary alkyl arenes—with olefins higher than ethylene. The dehydrogenation of acyclic alkanes to give alkylaromatics can be achieved using heterogeneous catalysts at high temperatures, but with low yields and low selectivity. We present here the first catalytic conversion of n-alkanes to alkylaromatics using homogeneous or molecular catalysts—specifically ‘pincer’-ligated iridium complexes—and olefinic hydrogen acceptors. For example, the reaction of n-octane affords up to 86% yield of aromatic product, primarily o-xylene and secondarily ethylbenzene. In the case of n-decane and n-dodecane, the resulting alkylarenes are exclusively unbranched (that is, n-alkyl-substituted), with selectivity for the corresponding o-(n-alkyl)toluene.

  1. Multivalent display of proteins on viral nanoparticles using molecular recognition and chemical ligation strategies.

    PubMed

    Venter, P Arno; Dirksen, Anouk; Thomas, Diane; Manchester, Marianne; Dawson, Philip E; Schneemann, Anette

    2011-06-13

    Multivalent display of heterologous proteins on viral nanoparticles forms a basis for numerous applications in nanotechnology, including vaccine development, targeted therapeutic delivery, and tissue-specific bioimaging. In many instances, precise placement of proteins is required for optimal functioning of the supramolecular assemblies, but orientation- and site-specific coupling of proteins to viral scaffolds remains a significant technical challenge. We have developed two strategies that allow for controlled attachment of a variety of proteins on viral particles using covalent and noncovalent principles. In one strategy, an interaction between domain 4 of anthrax protective antigen and its receptor was used to display multiple copies of a target protein on virus-like particles. In the other, expressed protein ligation and aniline-catalyzed oximation was used to display covalently a model protein. The latter strategy, in particular, yielded nanoparticles that induced potent immune responses to the coupled protein, suggesting potential applications in vaccine development. PMID:21545187

  2. Testing the feasibility of DNA typing for human identification by PCR and an oligonucleotide ligation assay

    SciTech Connect

    Delahunty, C.; Ankener, W.; Deng, Qiang

    1996-06-01

    The use of DNA typing in human genome analysis is increasing and finding widespread application in the area of forensic and paternity testing. In this report, we explore the feasibility of typing single nucleotide polymorphisms (SNPs) by using a semiautomated method for analyzing human DNA samples. In this approach, PCR is used to amplify segments of human DNA containing a common SNP. Allelic nucleotides in the amplified product are then typed by a calorimetric implementation of the oligonucleotide ligation assay (OLA). The results of the combined assay, PCR/OLA, are read directly by a spectrophotometer; the absorbances are compiled and the genotypes are automatically determined. A panel of 20 markers has been developed for DNA typing and has been tested using a sample panel from the CEPH pedigrees (CEPH parents). The results of this typing, as well as the potential to apply this method to larger populations, are discussed. 62 refs., 2 figs., 4 tabs.

  3. Simultaneous detection of DNA from 10 food allergens by ligation-dependent probe amplification.

    PubMed

    Ehlert, Alexandra; Demmel, Anja; Hupfer, Christine; Busch, Ulrich; Engel, Karl-Heinz

    2009-04-01

    The simultaneous detection of DNA from different allergenic food ingredients by a ligation-dependent probe amplification (LPA) system is described. The approach allows detection of several targets in a one-tube assay. Synthetic oligonucleotides were designed to detect DNA from peanuts, cashews, pecans, pistachios, hazelnuts, sesame seeds, macadamia nuts, almonds, walnuts and brazil nuts. The specificity of the system was tested with DNA from more than 50 plant and animal species. The sensitivity of the method was suitable to detect allergenic ingredients in the low mg kg(-1) range. The limit of detection (LOD) for single allergens in different food matrices was 5 mg kg(-1). The novel analytical strategy represents a useful tool for the surveillance of established legislation on food allergens within the European Union.

  4. Pancreatico-enteric fistula post pancreatic duct ligation for delayed haemorrhage complicating pancreaticoduodenectomy

    PubMed Central

    Vijay, Adarsh; Noaman, Islam; Mahfouz, Ahmed; Khawar, Mahwish; Khalaf, Hatem; Elaffandi, Ahmed

    2016-01-01

    Introduction Pancreatic fistula remains the main cause for postoperative morbidity following pancreaticoduodenectomy. The coincidence of sentinel bleed prior to post pancreatectomy haemorrhage (PPH) and pancreatic fistula is associated with very high mortality. Presentation of case We report a case of pancreaticoduodenectomy complicated by postoperative leak and hematemesis. Severe delayed haemorrhage from the pancreatico-jejunostomy necessitated re-laparotomy and complete disconnection of the pancreatic anastomosis. Hemodynamic instability precluded a pancreatectomy or creation of a new anastomosis. A follow up MRI done 3 weeks after the patient’s discharge demonstrated a fistulous tract causing a communication between both the pancreatic and biliary systems and the enteric loop. Discussion Spontaneous development a pancreatico-enteric fistula despite ligation of the pancreatic duct and complete disconnection of the pancreatic anastomosis has never been reported in literature to date. Conclusion Pancreatic duct occlusion may be considered over a completion pancreatectomy or revisional pancreatic anastomosis in hemodynamically unstable and challenging cases. PMID:26921533

  5. Nuclear Resonance Vibrational Spectra of Five-Coordinate Imidazole-ligated Iron(II) Porphyrinates

    PubMed Central

    Hu, Chuanjiang; Barabanschikov, Alexander; Ellison, Mary K.; Zhao, Jiyong; Alp, E. Ercan; Sturhahn, Wolfgang; Zgierski, Marek Z.; Sage, J. Timothy; Scheidt, W. Robert

    2012-01-01

    Nuclear resonance vibrational spectra have been obtained for six five-coordinate imidazole-ligated iron(II) porphyrinates, [Fe(Por)(L)] (Por = tetraphenylporphyrinate, octaethylporphyrinate, tetratolylporphyrinate or protoporphyrinate IX and L = 2-methylimidazole or 1,2-dimethylimidazole). Measurements have been made on both powder and oriented crystal samples. The spectra are dominated by strong signals around 200–300 cm−1. Although the in-plane and out-of-plane vibrations are seriously overlapped, oriented crystal spectra allow their deconvolution. Thus, oriented crystal experimental data, along with DFT calculations, enable the assignment of key vibrations in the spectra. Molecular dynamics are also discussed. The nature of the Fe–NIm vibrations has been elaborated further than was possible from resonance Raman studies. Our study suggests that the Fe motions are coupled with the porphyrin core and peripheral groups motions. Both peripheral groups and their conformations have significant influence on the vibrational spectra (position and shape). PMID:22243131

  6. Multiplex ligation-dependent probe amplification: a novel approach for genetic diagnosis of Porphyria.

    PubMed

    Di Pierro, Elena; Brancaleoni, Valentina; Besana, Valeria; Cappellini, Maria Domenica

    2009-08-01

    Porphyrias are disorders caused by the genetic defects of enzymes of the heme pathway and are characterized by such a wide genetic heterogeneity that even the molecular analysis is not always decisive for a correct diagnosis. In the past few years, deletion with a size range of few kilobase pairs have been reported. These peculiar mutations, missed by both sequencing and cytogenetic techniques, have been identified by time consuming and technically demanding methods. To provide a rapid and sensitive method for the detection of deletions responsible for porphyria, we successfully designed and tested seven chemically synthesized probe sets specific for each heme gene and their flanking regions, to be used in multiplex ligation-dependent probe amplification technique.

  7. Size-dependent assembly of ligated gold nanocrystals in two dimensions

    NASA Astrophysics Data System (ADS)

    Liu, X. P.; Ni, Y.; He, L. H.

    2016-11-01

    Brownian dynamics (BD) simulation based on a coarse-grained model is performed to study the assembly of dodecanethiol-ligated Au nanocrystals (NCs) at a toluene-air interface. With increasing diameter from 3 nm to 9 nm, the NCs are found to form three different phases—a dispersed phase without aggregation, a mixture of dispersed NCs and rounded clusters, and a compactly packed solid phase of the fractal structure. Such size dependence of the assembled phase is attributed to the variation in the well depth {{ Φ }c} of the interaction potential between NCs, and the value of {{ Φ }c}=-3.5{{K}\\text{B}}T for 6 nm NCs turns out to be most suitable to form monolayers with hexagonal packing. The result is of universal importance for assembling complete monolayers, because the valley of the interaction potential can be well tailored by properly choosing the NC size, ligand length and solvent.

  8. The dawn of the RNA World: Toward functional complexity through ligation of random RNA oligomers

    PubMed Central

    Briones, Carlos; Stich, Michael; Manrubia, Susanna C.

    2009-01-01

    A main unsolved problem in the RNA World scenario for the origin of life is how a template-dependent RNA polymerase ribozyme emerged from short RNA oligomers obtained by random polymerization on mineral surfaces. A number of computational studies have shown that the structural repertoire yielded by that process is dominated by topologically simple structures, notably hairpin-like ones. A fraction of these could display RNA ligase activity and catalyze the assembly of larger, eventually functional RNA molecules retaining their previous modular structure: molecular complexity increases but template replication is absent. This allows us to build up a stepwise model of ligation-based, modular evolution that could pave the way to the emergence of a ribozyme with RNA replicase activity, step at which information-driven Darwinian evolution would be triggered. PMID:19318464

  9. Treatment of idiopathic chylothorax in 14 dogs by ligation of the thoracic duct and partial pericardiectomy.

    PubMed

    Carobbi, B; White, R A S; Romanelli, G

    The outcome and complications associated with thoracic duct ligation combined with partial pericardiectomy in 14 dogs with idiopathic chylothorax were investigated retrospectively. Nine of the dogs were treated in the uk and five in Italy. All of them were reassessed clinically four weeks after surgery and the respiratory function and any pleural fluid accumulation were evaluated; they were followed up by telephone contact for at least six months. Eleven of the dogs were clinically normal and had no radiographic signs of pleural effusion when reassessed after four weeks. Two showed radiographic signs of a minor accumulation of pleural fluid but were clinically normal; when reassessed after three months they showed similar radiographic signs and clinical findings; but after four months there was no evidence of pleural effusion. One dog had a major complication that required a second surgical intervention. PMID:19103616

  10. ECM-incorporated hydrogels cross-linked via native chemical ligation to engineer stem cell microenvironments.

    PubMed

    Jung, Jangwook P; Sprangers, Anthony J; Byce, John R; Su, Jing; Squirrell, Jayne M; Messersmith, Phillip B; Eliceiri, Kevin W; Ogle, Brenda M

    2013-09-01

    Limiting the precise study of the biochemical impact of whole molecule extracellular matrix (ECM) proteins on stem cell differentiation is the lack of 3D in vitro models that can accommodate many different types of ECM. Here we sought to generate such a system while maintaining consistent mechanical properties and supporting stem cell survival. To this end, we used native chemical ligation to cross-link poly(ethylene glycol) macromonomers under mild conditions while entrapping ECM proteins (termed ECM composites) and stem cells. Sufficiently low concentrations of ECM were used to maintain constant storage moduli and pore size. Viability of stem cells in composites was maintained over multiple weeks. ECM of composites encompassed stem cells and directed the formation of distinct structures dependent on ECM type. Thus, we introduce a powerful approach to study the biochemical impact of multiple ECM proteins (either alone or in combination) on stem cell behavior.

  11. The response of human dendritic cells to co-ligation of pattern-recognition receptors.

    PubMed

    Dzopalic, Tanja; Rajkovic, Ivan; Dragicevic, Ana; Colic, Miodrag

    2012-04-01

    Dendritic cells (DCs) are key antigen-presenting cells that express a wide variety of pattern-recognition receptors (PRRs). Triggering of a single PRR, especially Toll-like receptors (TLRs) and C-type lectins, induces maturation of DCs, but cooperativity between multiple PRRs is needed in order to achieve an effective immune response. In this review, we summarize the published data related to the effect of individual and joint PRR agonists on DCs and Langerhans-like cells derived from monocytes (MoDCs and MoLCs, respectively). Our results demonstrate that MoDCs co-stimulated with TLR3/TLR7 and TLR3/Dectin-1 ligands induced superior T helper (Th)1 and Th17 immune responses, compared to effects of single agonists. The opposite outcome was observed after co-ligation of TLR3 and Langerin on MoLCs. These findings may be relevant to improve strategy for tumor immunotherapy.

  12. The Pancreatic Duct Ligated (Mini)pig as a Model for Pancreatic Exocrine Insufficiency in Man.

    PubMed

    Gregory, Peter Colin; Hoffmann, Katrin; Kamphues, Josef; Möeler, Anne

    2016-10-01

    Modern therapy of pancreatic exocrine insufficiency (PEI) using pancreatic enzyme replacement therapy (PERT) has largely been very effective and has greatly helped in improving the nutritional status of patients with PEI and in increasing the life expectancy in cystic fibrosis. It is believed that the use of predictable large animal models could play an important role in assessing and developing new therapies. This article reviews the pancreatic duct ligated (adult) minipig as a chronic model of total PEI, with a detailed look at the influence of PEI and response to PERT on prececal compared to fecal digestibility, to directly investigate effects on protein and starch digestion and absorption. In addition, the piglet with PEI is reviewed as a model for PEI in young patients with the aim of further improving the therapy and nutritional status of young patients with cystic fibrosis. PMID:27623555

  13. Assessing long-distance RNA sequence connectivity via RNA-templated DNA–DNA ligation

    PubMed Central

    Roy, Christian K; Olson, Sara; Graveley, Brenton R; Zamore, Phillip D; Moore, Melissa J

    2015-01-01

    Many RNAs, including pre-mRNAs and long non-coding RNAs, can be thousands of nucleotides long and undergo complex post-transcriptional processing. Multiple sites of alternative splicing within a single gene exponentially increase the number of possible spliced isoforms, with most human genes currently estimated to express at least ten. To understand the mechanisms underlying these complex isoform expression patterns, methods are needed that faithfully maintain long-range exon connectivity information in individual RNA molecules. In this study, we describe SeqZip, a methodology that uses RNA-templated DNA–DNA ligation to retain and compress connectivity between distant sequences within single RNA molecules. Using this assay, we test proposed coordination between distant sites of alternative exon utilization in mouse Fn1, and we characterize the extraordinary exon diversity of Drosophila melanogaster Dscam1. DOI: http://dx.doi.org/10.7554/eLife.03700.001 PMID:25866926

  14. [Experimental results after acute and chronic ligation of bile duct (author's transl)].

    PubMed

    Kirchner, R; Hartung, H; Trendelenburg, C

    1980-08-01

    The bile duct was ligated in 14 bastard dogs. Bilirubine, alcaline phosphatase, GOT, GPT, GLDH, and gamma GT were measured pre- and postoperatively. On the 8th postoperative day stenosis of the choledochus was eliminated using a patch plasty for dilatation in 7 dogs, whereas the occlusion remained in the other 7 dogs. Laboratory and histological results were characteristic for cholestasis 8 days after occlusion; these changes disappeared within 4 weeks after patch plastic surgery. In the controls these parameters normalized as well within 8 weeks, in spite of the persisting occlusion. These results show, that pathological changes after short term cholestasis are fully reversible; they demonstrate as well, that there are compensatory mechanisms operating in dogs with permanent occlusion of the bile duct.

  15. Complex in vivo Ligation Using Homologous Recombination and High-efficiency Plasmid Rescue from Saccharomyces cerevisiae

    PubMed Central

    Finnigan, Gregory C.; Thorner, Jeremy

    2015-01-01

    The protocols presented here allow for the facile generation of a wide variety of complex multipart DNA constructs (tagged gene products, gene fusions, chimeric proteins, and other variants) using homologous recombination and in vivo ligation in budding yeast (Saccharomyces cerevisiae). This method is straightforward, efficient and cost-effective, and can be used both for vector creation and for subsequent one-step, high frequency integration into a chromosomal locus in yeast. The procedure utilizes PCR with extended oligonucleotide “tails” of homology between multiple fragments to allow for reassembly in yeast in a single transformation followed by a method for highly efficient plasmid extraction from yeast (for transformation into bacteria). The latter is an improvement on existing methods of yeast plasmid extraction, which, historically, has been a limiting step in recovery of desired constructs. We describe the utility and convenience of our techniques, and provide several examples. PMID:26523287

  16. ECM-incorporated hydrogels crosslinked 1 via native chemical ligation to engineer stem cell microenvironments

    PubMed Central

    Jung, Jangwook P.; Sprangers, Anthony J.; Byce, John R.; Su, Jing; Squirrell, Jayne M.; Messersmith, Phillip B.; Eliceiri, Kevin W.; Ogle, Brenda M.

    2013-01-01

    Limiting the precise study of the biochemical impact of whole molecule extracellular matrix (ECM) proteins on stem cell differentiation is the lack of 3D in vitro models that can accommodate many different types of ECM. Here we sought to generate such a system while maintaining consistent mechanical properties and supporting stem cell survival. To this end, we used native chemical ligation to crosslink poly(ethylene glycol) macromonomers under mild conditions while entrapping ECM proteins (termed ECM composites) and stem cells. Sufficiently low concentrations of ECM were used to maintain constant storage moduli and pore size. Viability of stem cells in composites was maintained over multiple weeks. ECM of composites encompassed stem cells and directed the formation of distinct structures dependent on ECM type. Thus, we introduce a powerful approach to study the biochemical impact of multiple ECM proteins (either alone or in combination) on stem cell behavior. PMID:23875943

  17. Highly specific and sensitive electrochemical genotyping via gap ligation reaction and surface hybridization detection.

    PubMed

    Huang, Yong; Zhang, Yan-Li; Xu, Xiangmin; Jiang, Jian-Hui; Shen, Guo-Li; Yu, Ru-Qin

    2009-02-25

    This paper developed a novel electrochemical genotyping strategy based on gap ligation reaction with surface hybridization detection. This strategy utilized homogeneous enzymatic reactions to generate molecular beacon-structured allele-specific products that could be cooperatively annealed to capture probes stably immobilized on the surface via disulfide anchors, thus allowing ultrasensitive surface hybridization detection of the allele-specific products through redox tags in close proximity to the electrode. Such a unique biphasic architecture provided a universal methodology for incorporating enzymatic discrimination reactions in electrochemical genotyping with desirable reproducibility, high efficiency and no interferences from interficial steric hindrance. The developed technique was demonstrated to show intrinsic high sensitivity for direct genomic analysis, and excellent specificity with discriminativity of single nucleotide variations.

  18. Design and synthesis of highly reactive dienophiles for the tetrazine-trans-cyclooctene ligation.

    PubMed

    Taylor, Michael T; Blackman, Melissa L; Dmitrenko, Olga; Fox, Joseph M

    2011-06-29

    Computation was used to design a trans-cyclooctene derivative that displays enhanced reactivity in the tetrazine-trans-cycloctene ligation. The optimized derivative is an (E)-bicyclo[6.1.0]non-4-ene with a cis-ring fusion, in which the eight-membered ring is forced to adopt a highly strained 'half-chair' conformation. Toward 3,6-dipyridyl-s-tetrazine in MeOH at 25 °C, the strained derivative is 19 and 27 times more reactive than the parent trans-cyclooctene and 4E-cyclooct-4-enol, respectively. Toward 3,6-diphenyl-s-tetrazine in MeOH at 25 °C, the strained derivative is 160 times more reactive than the parent trans-cyclooctene.

  19. Size-dependent assembly of ligated gold nanocrystals in two dimensions.

    PubMed

    Liu, X P; Ni, Y; He, L H

    2016-11-01

    Brownian dynamics (BD) simulation based on a coarse-grained model is performed to study the assembly of dodecanethiol-ligated Au nanocrystals (NCs) at a toluene-air interface. With increasing diameter from 3 nm to 9 nm, the NCs are found to form three different phases-a dispersed phase without aggregation, a mixture of dispersed NCs and rounded clusters, and a compactly packed solid phase of the fractal structure. Such size dependence of the assembled phase is attributed to the variation in the well depth [Formula: see text] of the interaction potential between NCs, and the value of [Formula: see text] for 6 nm NCs turns out to be most suitable to form monolayers with hexagonal packing. The result is of universal importance for assembling complete monolayers, because the valley of the interaction potential can be well tailored by properly choosing the NC size, ligand length and solvent. PMID:27605114

  20. The Pancreatic Duct Ligated (Mini)pig as a Model for Pancreatic Exocrine Insufficiency in Man.

    PubMed

    Gregory, Peter Colin; Hoffmann, Katrin; Kamphues, Josef; Möeler, Anne

    2016-10-01

    Modern therapy of pancreatic exocrine insufficiency (PEI) using pancreatic enzyme replacement therapy (PERT) has largely been very effective and has greatly helped in improving the nutritional status of patients with PEI and in increasing the life expectancy in cystic fibrosis. It is believed that the use of predictable large animal models could play an important role in assessing and developing new therapies. This article reviews the pancreatic duct ligated (adult) minipig as a chronic model of total PEI, with a detailed look at the influence of PEI and response to PERT on prececal compared to fecal digestibility, to directly investigate effects on protein and starch digestion and absorption. In addition, the piglet with PEI is reviewed as a model for PEI in young patients with the aim of further improving the therapy and nutritional status of young patients with cystic fibrosis.

  1. Automated DNA diagnostics using an ELISA-based oligonucleotide ligation assay.

    PubMed Central

    Nickerson, D A; Kaiser, R; Lappin, S; Stewart, J; Hood, L; Landegren, U

    1990-01-01

    DNA diagnostics, the detection of specific DNA sequences, will play an increasingly important role in medicine as the molecular basis of human disease is defined. Here, we demonstrate an automated, nonisotopic strategy for DNA diagnostics using amplification of target DNA segments by the polymerase chain reaction (PCR) and the discrimination of allelic sequence variants by a colorimetric oligonucleotide ligation assay (OLA). We have applied the automated PCR/OLA procedure to diagnosis of common genetic diseases, such as sickle cell anemia and cystic fibrosis (delta F508 mutation), and to genetic linkage mapping of gene segments in the human T-cell receptor beta-chain locus. The automated PCR/OLA strategy provides a rapid system for diagnosis of genetic, malignant, and infectious diseases as well as a powerful approach to genetic linkage mapping of chromosomes and forensic DNA typing. Images PMID:2247466

  2. Simultaneous detection of DNA from 10 food allergens by ligation-dependent probe amplification.

    PubMed

    Ehlert, Alexandra; Demmel, Anja; Hupfer, Christine; Busch, Ulrich; Engel, Karl-Heinz

    2009-04-01

    The simultaneous detection of DNA from different allergenic food ingredients by a ligation-dependent probe amplification (LPA) system is described. The approach allows detection of several targets in a one-tube assay. Synthetic oligonucleotides were designed to detect DNA from peanuts, cashews, pecans, pistachios, hazelnuts, sesame seeds, macadamia nuts, almonds, walnuts and brazil nuts. The specificity of the system was tested with DNA from more than 50 plant and animal species. The sensitivity of the method was suitable to detect allergenic ingredients in the low mg kg(-1) range. The limit of detection (LOD) for single allergens in different food matrices was 5 mg kg(-1). The novel analytical strategy represents a useful tool for the surveillance of established legislation on food allergens within the European Union. PMID:19680915

  3. Induction of Sca-1 via activation of STAT3 system in the duct cells of the mouse submandibular gland by ligation of the main excretory duct.

    PubMed

    Purwanti, Nunuk; Karabasil, Mileva Ratko; Matsuo, Shinsuke; Chen, Gang; Javkhlan, Purevjav; Azlina, Ahmad; Hasegawa, Takahiro; Yao, Chenjuan; Akamatsu, Tetsuya; Hosoi, Kazuo

    2011-11-01

    To examine the very initial step that takes place immediately after tissue injury and is linked to tissue regeneration, we employed the submandibular gland (SMG), which was injured by ligation of its main excretory duct (MED). Ligation of the MED of the SMG in mice induced the expression of Sca-1, a protein marker of hematopoietic stem cells. In the normal gland, a low level of Sca-1 was expressed, which was localized predominantly in the excretory duct cells. At 1 day after ligation, Sca-1 expression increased prominently in almost all of cells in the duct system, but not in the acinar cells. The level of Sca-1 mRNA had begun to increase at 6 h after ligation and continuously rose thereafter until it reached a plateau, which occurred ∼12 h after ligation. STAT3 phosphorylated at its tyrosine-705 (p-STAT3) in the ligated gland increased immediately after ligation, and it was localized in the nuclei of all duct cells. The results of an EMSA revealed the specific binding of a nuclear extract to the sequence of the γ-interferon activation site (GAS) present in the Sca-1 promoter and confirmed that such binding increased after ligation. Thus the present study suggests that STAT3, having been phosphorylated following MED ligation, was transferred to the nucleus, where it bound to the GAS element in the promoter of Sca-1 gene, resulting in promotion of Sca-1 gene expression. Actual prevention of STAT3 phosphorylation reduced the ligation-induced Sca-1 elevation.

  4. External Carotid Artery Ligation in Squamous Cell Carcinomas of the Oral Cavity and Oropharynx: an Oncological Emergency.

    PubMed

    Kumar, Tarun; Yadav, Vijay; Ravi, K; Ramaswamy, Kartikeyan; Patel, Mahesh H; Kothari, Kiran

    2015-12-01

    The purpose of this study is to investigate the outcomes of emergency external carotid artery ligation in head and neck cancer patients. It is a retrospective observational study of 11 patients with oral cavity and oropharynx cancers who underwent external carotid ligation as an emergency procedure. Prior tracheostomy was done in all the patients as part of the procedure. Parameters studied were the efficacy and safety of the procedure in the form of control of haemorrhage, any postoperative neurological deficit, morbidity and mortality. The study evaluates the efficacy of the intervention purely as an emergency procedure, and oncological outcomes have not been reported. Analysis was done using simple frequencies and proportions. The oropharynx is the most common site of tumour bleeding in head and neck malignancies. Bleeding following external carotid ligation stopped in all the patients immediately without any postoperative mortality or morbidity. No patient had any neurologic deficits postoperatively. There was one case of rebleeding. Emergency external carotid ligation in tumours of the oral cavity and oropharynx is a life-saving and simple procedure with limited morbidity. Prior tracheostomy is recommended in all the patients. PMID:27011469

  5. Primary amine stabilization of a dicopper(III) bis(μ-oxo) species: modeling the ligation in pMMO.

    PubMed

    Citek, Cooper; Lin, Bo-Lin; Phelps, Tim E; Wasinger, Erik C; Stack, T Daniel P

    2014-10-15

    Here we report the formation of the first examples of dicopper(III) bis(μ-oxo) complexes ligated by the primary amines, propylenediamine, and N,N,-dimethyl propylenediamine. Stabilization of these new compounds is effected at -125 °C by "core capture"- introduction of exogenous ligand to a preformed dicopper(III) bis(μ-oxo) complex supported by the peralkylated tetramethyl propylenediamine. Primary amine ligation in these compounds matches the single primary amine coordination of the putative active site of particulate methane monooxygenase (pMMO) and polysaccharide monooxygenase. Reactivity studies presented here show primary amine ligated cores are competent oxidants, capable of activating C-H bonds by an H-atom abstraction mechanism. Trends in spectroscopy, structure, and reactivity provide hints to the potential role of primary amine ligation in pMMO: increased substrate accessibility to the redox active orbitals of the Cu2O2 core and greater stabilization of the oxidant without attenuation of oxidizing power.

  6. Evaluation of the force generated by gradual deflection of orthodontic wires in conventional metallic, esthetic, and self-ligating brackets

    PubMed Central

    Francisconi, Manoela Fávaro; Janson, Guilherme; Henriques, José Fernando Castanha; de Freitas, Karina Maria Salvatore

    2016-01-01

    ABSTRACT Objective: The purpose of this study was to evaluate the deflection forces of Nitinol orthodontic wires placed in different types of brackets: metallic, reinforced polycarbonate with metallic slots, sapphire, passive and active self-ligating, by assessing strength values variation according to gradual increase in wire diameter and deflection and comparing different combinations in the different deflections. Material and Methods: Specimens were set in a clinical simulation model and evaluated in a Universal Testing Machine (INSTRON 3342), using the ISO 15841 protocol. Data were subjected to One-way ANOVA, followed by Tukey tests (p<0.05). Results: Self-ligating brackets presented the most similar behavior to each other. For conventional brackets there was no consistent behavior for any of the deflections studied. Conclusions: Self-ligating brackets presented the most consistent and predictable results while conventional brackets, as esthetic brackets, showed very different patterns of forces. Self-ligating brackets showed higher strength in all deflections when compared with the others, in 0.020-inch wires.

  7. New bipolar tissue ligator combines constant tissue compression and temperature guidance: histologic study and implications for treatment of hemorrhoids

    PubMed Central

    Piskun, Gregory; Tucker, Robert

    2012-01-01

    Background Several minimally invasive technologies are available to treat common soft tissue lesions including symptomatic hemorrhoids. The use of energy to deliver heat and coagulate target lesions is commonly practiced. This study compares the histologic effects produced on intestinal tissues by two energy-based systems which employ different approaches of heat delivery. Methods Two heat delivery systems were evaluated in vivo in a single porcine subject: infrared coagulator and bipolar tissue ligator utilizing constant tissue compression and temperature guidance. Eighteen treatment sites divided into three groups of six were assessed. Treatment site temperature was measured and the effects of thermal treatment in the mucosa, submucosa, submucosal vessels, and muscularis layer were scored. Lateral thermal spread beyond the energy application site was also assessed. Results Treatment site temperatures were much lower in the bipolar ligator group than in the infrared coagulator group. The mucosal and submucosal tissue changes observed in tissues treated with infrared energy and bipolar energy at 55°C were similar. Both the mucosal and submucosal tissue changes with bipolar energy at 50°C were significantly less. Conclusion Both devices achieved similar histologic results. However, the unique design of the bipolar ligator, which allows consistent capture, constant compression, and temperature monitoring of target tissue, accomplished the desired histologic changes with less muscular damage at much lower temperatures than the infrared coagulator. The use of bipolar ligation could offer clinical advantages such as reduced patient pain and a minimized chance of heat-related collateral tissue damage. PMID:23152714

  8. Local anaesthetic infiltration for the rubber band ligation of early symptomatic haemorrhoids: a systematic review and meta-analysis.

    PubMed

    Sajid, M S; Bhatti, M I; Caswell, J; Sains, P; Baig, M K

    2015-03-01

    The objective of this article is to systematically analyse the randomized, controlled trials evaluating the effectiveness of local anaesthetic infiltration prior to the rubber band ligation of early symptomatic haemorrhoids. Published randomized, controlled trials comparing the use of local anaesthetic (LA) versus no-local anaesthetic (NLA) for the rubber band ligation of early symptomatic haemorrhoids were analysed using RevMan®, and the combined outcomes were expressed as odds ratios (OR) and standardized mean difference (SMD). Four randomized, controlled trials evaluating 387 patients were retrieved from the standard electronic databases. The risk of treatment failure (OR 0.44; 95% CI 0.07, 2.79; z = 0.87; p = 0.39) and post-procedure complications (OR 0.48; 95% CI 0.08, 2.76; z = 0.83; p = 0.41) was similar between two techniques. However, the post-procedure pain score (SMD -5.19; 95% CI -9.08, -1.30; z = 2.62; p < 0.009) was significantly lower in the group of patients undergoing rubber band ligation of haemorrhoids under local anaesthetic injection. The use of LA appears to have clinically measurable advantages over NLA in the rubber band ligation of early symptomatic haemorrhoids to lessen post-procedure pain.

  9. Synthesis of histone proteins by CPE ligation using a recombinant peptide as the C-terminal building block.

    PubMed

    Kawakami, Toru; Yoshikawa, Ryo; Fujiyoshi, Yuki; Mishima, Yuichi; Hojo, Hironobu; Tajima, Shoji; Suetake, Isao

    2015-11-01

    The post-translational modification of histones plays an important role in gene expression. We report herein on a method for synthesizing such modified histones by ligating chemically prepared N-terminal peptides and C-terminal recombinant peptide building blocks. Based on their chemical synthesis, core histones can be categorized as two types; histones H2A, H2B and H4 which contain no Cys residues, and histone H3 which contains a Cys residue(s) in the C-terminal region. A combination of native chemical ligation and desulphurization can be simply used to prepare histones without Cys residues. For the synthesis of histone H3, the endogenous Cys residue(s) must be selectively protected, while keeping the N-terminal Cys residue of the C-terminal building block that is introduced for purposes of chemical ligation unprotected. To this end, a phenacyl group was successfully utilized to protect endogenous Cys residue(s), and the recombinant peptide was ligated with a peptide containing a Cys-Pro ester (CPE) sequence as a thioester precursor. Using this approach it was possible to prepare all of the core histones H2A, H2B, H3 and H4 with any modifications. The resulting proteins could then be used to prepare a core histone library of proteins that have been post-translationally modified.

  10. Size-dependent stability toward dissociation and ligand binding energies of phosphine-ligated gold cluster ions

    SciTech Connect

    Johnson, Grant E.; Priest, Thomas A.; Laskin, Julia

    2014-01-01

    The stability of sub-nanometer size gold clusters ligated with organic molecules is of paramount importance to the scalable synthesis of monodisperse size-selected metal clusters with highly tunable chemical and physical properties. For the first time, a Fourier transform ion cyclotron resonance mass spectrometer (FT-ICR-MS) equipped with surface induced dissociation (SID) has been employed to investigate the time and collision energy resolved fragmentation behavior of cationic doubly charged gold clusters containing 7-9 gold atoms and 6-7 triphenylphosphine (TPP) ligands prepared by reduction synthesis in solution. The TPP ligated gold clusters are demonstrated to fragment through three primary dissociation pathways: (1) Loss of a neutral TPP ligand from the precursor gold cluster, (2) asymmetric fission and (3) symmetric fission and charge separation of the gold core resulting in formation of complementary pairs of singly charged fragment ions. Threshold energies and activation entropies of these fragmentation pathways have been determined employing Rice-Ramsperger-Kassel-Marcus (RRKM) modeling of the experimental SID data. It is demonstrated that the doubly charged cluster ion containing eight gold atoms and six TPP ligands, (8,6)2+, exhibits exceptional stability compared to the other cationic gold clusters examined in this study due to its large ligand binding energy of 1.76 eV. Our findings demonstrate the dramatic effect of the size and extent of ligation on the gas-phase stability and preferred fragmentation pathways of small TPP-ligated gold clusters.

  11. Primary amine stabilization of a dicopper(III) bis(μ-oxo) species: modeling the ligation in pMMO.

    PubMed

    Citek, Cooper; Lin, Bo-Lin; Phelps, Tim E; Wasinger, Erik C; Stack, T Daniel P

    2014-10-15

    Here we report the formation of the first examples of dicopper(III) bis(μ-oxo) complexes ligated by the primary amines, propylenediamine, and N,N,-dimethyl propylenediamine. Stabilization of these new compounds is effected at -125 °C by "core capture"- introduction of exogenous ligand to a preformed dicopper(III) bis(μ-oxo) complex supported by the peralkylated tetramethyl propylenediamine. Primary amine ligation in these compounds matches the single primary amine coordination of the putative active site of particulate methane monooxygenase (pMMO) and polysaccharide monooxygenase. Reactivity studies presented here show primary amine ligated cores are competent oxidants, capable of activating C-H bonds by an H-atom abstraction mechanism. Trends in spectroscopy, structure, and reactivity provide hints to the potential role of primary amine ligation in pMMO: increased substrate accessibility to the redox active orbitals of the Cu2O2 core and greater stabilization of the oxidant without attenuation of oxidizing power. PMID:25268334

  12. Synthesis of histone proteins by CPE ligation using a recombinant peptide as the C-terminal building block.

    PubMed

    Kawakami, Toru; Yoshikawa, Ryo; Fujiyoshi, Yuki; Mishima, Yuichi; Hojo, Hironobu; Tajima, Shoji; Suetake, Isao

    2015-11-01

    The post-translational modification of histones plays an important role in gene expression. We report herein on a method for synthesizing such modified histones by ligating chemically prepared N-terminal peptides and C-terminal recombinant peptide building blocks. Based on their chemical synthesis, core histones can be categorized as two types; histones H2A, H2B and H4 which contain no Cys residues, and histone H3 which contains a Cys residue(s) in the C-terminal region. A combination of native chemical ligation and desulphurization can be simply used to prepare histones without Cys residues. For the synthesis of histone H3, the endogenous Cys residue(s) must be selectively protected, while keeping the N-terminal Cys residue of the C-terminal building block that is introduced for purposes of chemical ligation unprotected. To this end, a phenacyl group was successfully utilized to protect endogenous Cys residue(s), and the recombinant peptide was ligated with a peptide containing a Cys-Pro ester (CPE) sequence as a thioester precursor. Using this approach it was possible to prepare all of the core histones H2A, H2B, H3 and H4 with any modifications. The resulting proteins could then be used to prepare a core histone library of proteins that have been post-translationally modified. PMID:26002961

  13. Effects of bile duct ligation and captopril on salt appetite and renin-aldosterone axis in rats.

    PubMed

    Lane, J R; Starbuck, E M; Johnson, A K; Fitts, D A

    1999-05-01

    A ligation of the common bile duct (BDL) produces cholestasis and hypotension and increases the daily ingestion of sodium chloride solutions in rats. Low-dose captopril (CAP) treatment also modifies the ingestion of water and sodium in naive rats, and may do so in cholestatic rats. This study examined whether the elevated ingestion of saline by Long-Evans rats after BDL is associated with increased plasma renin activity (PRA), and whether treatment with a low dose of the angiotensin converting-enzyme inhibitor CAP further exacerbates fluid intake and PRA after BDL. In these experiments water and 0.3 M saline intake and PRA and plasma aldosterone (PA) were measured in naive and CAP-treated BDL and sham-ligated rats. We found that BDL elevated rats' daily saline intake 2 weeks after the ligation procedure but had no effect on PRA. CAP (0.1 mg/mL) placed in the drinking water of some BDL rats further increased saline intake. Both PA and hematocrits tended to be reduced in BDL rats, whereas PRA was elevated in both BDL and sham-ligated rats receiving CAP in the drinking water or by gavage (0.1 mg/mL in 10 mL/kg). The data suggest that the ingestion of saline by rats can be modified by BDL and CAP administration, but that exaggerated saline intake in BDL rats is not associated with excessive renin secretion. PMID:10357430

  14. External Carotid Artery Ligation in Squamous Cell Carcinomas of the Oral Cavity and Oropharynx: an Oncological Emergency.

    PubMed

    Kumar, Tarun; Yadav, Vijay; Ravi, K; Ramaswamy, Kartikeyan; Patel, Mahesh H; Kothari, Kiran

    2015-12-01

    The purpose of this study is to investigate the outcomes of emergency external carotid artery ligation in head and neck cancer patients. It is a retrospective observational study of 11 patients with oral cavity and oropharynx cancers who underwent external carotid ligation as an emergency procedure. Prior tracheostomy was done in all the patients as part of the procedure. Parameters studied were the efficacy and safety of the procedure in the form of control of haemorrhage, any postoperative neurological deficit, morbidity and mortality. The study evaluates the efficacy of the intervention purely as an emergency procedure, and oncological outcomes have not been reported. Analysis was done using simple frequencies and proportions. The oropharynx is the most common site of tumour bleeding in head and neck malignancies. Bleeding following external carotid ligation stopped in all the patients immediately without any postoperative mortality or morbidity. No patient had any neurologic deficits postoperatively. There was one case of rebleeding. Emergency external carotid ligation in tumours of the oral cavity and oropharynx is a life-saving and simple procedure with limited morbidity. Prior tracheostomy is recommended in all the patients.

  15. Holoturia arenicola extract modulates bile duct ligation-induced oxidative stress in rat kidney

    PubMed Central

    Fahmy, Sohair R; Mohamed, Ayman S

    2015-01-01

    Background: Acute Renal Failure (ARF) in patients with cirrhosis is one of the most frequently encountered complications of obstructive jaundice. Marine organisms from the Mediterranean Coast of Egypt are considered potential sources of bioactive molecules. The present study was undertaken to explore the curative effects of Holothuria arenicola extract (HaE) against renal injury induced by bile duct ligation in male albino rats. Methods: Fifty four male Wistar albino rats were assigned into two main groups, the Sham-operated control (received distilled water only for 28 days) and bile duct ligated (BDL) group, which divided into 2 subgroups, animals of these subgroups treated for 28 consecutive days as follow: Subgroup I (BDL), rats of this subgroup administered distilled water orally. Subgroup II, animals of this subgroup treated orally with HaE (200 mg/kg body weight). Results: BDL induced marked alteration on renal functions as manifested by a significant increase in the kidney function markers, serum creatinine, urea and uric acid. In addition, BDL caused significant increase in MDA level and significant decrease in GSH level as well as antioxidant enzymes activities (GST, SOD and CAT). However, administration of HaE for consecutive 28 days significantly reversed these changes, suggesting that the renal curative effect of HaE against oxidative stress- induced injury might be involved in decreasing lipid peroxide generation and stimulating antioxidant status. Conclusion: The present study revealed that HaE had a profound effect against BDL-induced oxidative stress in the kidney tissues which is the common feature of choestasis in the liver. PMID:25973050

  16. In vivo CD40 ligation can induce T-cell-independent antitumor effects that involve macrophages.

    PubMed

    Lum, Hillary D; Buhtoiarov, Ilia N; Schmidt, Brian E; Berke, Gideon; Paulnock, Donna M; Sondel, Paul M; Rakhmilevich, Alexander L

    2006-06-01

    We have previously demonstrated T cell-independent antitumor and antimetastatic effects of CD40 ligation that involved natural killer (NK) cells. As CD40 molecules are expressed on the surface of macrophages (Mphi), we hypothesized that Mphi may also serve as antitumor effector cells when activated by CD40 ligation. Progression of subcutaneous NXS2 murine neuroblastomas was delayed significantly by agonistic CD40 monoclonal antibody (anti-CD40 mAb) therapy in immunocompetent A/J mice, as well as in T and B cell-deficient severe combined immunodeficiency (SCID) mice. Although NK cells can be activated by anti-CD40 mAb, anti-CD40 mAb treatment also induced a significant antitumor effect in SCID/beige mice in the absence of T and NK effector cells, even when noncytolytic NK cells and polymorphonuclear cells (PMN) were depleted. Furthermore, in vivo treatment with anti-CD40 mAb resulted in enhanced expression of cytokines and cell surface activation markers, as well as Mphi-mediated tumor inhibition in A/J mice, C57BL/6 mice, and SCID/beige mice, as measured in vitro. A role for Mphi was shown by reduction in the antitumor effect of anti-CD40 mAb when Mphi functions were inhibited in vivo by silica. In addition, activation of peritoneal Mphi by anti-CD40 mAb resulted in survival benefits in mice bearing intraperitoneal tumors. Taken together, our results show that anti-CD40 mAb immunotherapy of mice can inhibit tumor growth in the absence of T cells, NK cells, and PMN through the involvement of activated Mphi.

  17. Vascular Z-shaped ligation technique in surgical treatment of haemorrhoid

    PubMed Central

    Gemici, Kazım; Okuş, Ahmet; Ay, Serden

    2015-01-01

    AIM: To present the effectiveness of minimal invasive vascular zet ligation in the surgical treatment of haemorrhoidal disease (HD). METHODS: Among 138 patients with 2nd-4th grade internal HD having several complaints and operated at our hospital between 2003-2013; 116 patients who regularly attended 1-year control were included in the study. Operation times, postoperative early period pain, satisfaction score, complications and relapse details were obtained from computer records retrospectively. Visual Analogous Scale (VAS) scores were used for patient satisfaction on the 3rd, 7th and 21st days. Technique; fixed suture which is constituted by the first leg of the Z-shaped suture (to pass by the mucosa and muscular layer) was put in the pile root in order to ensure vascular ligation and fixation. The second leg of the Z-shaped suture is constituted by mobile suture and it passes by the pile mucosa and submucosa which prolapses 5-10 mm below the first suture. RESULTS: Seventy-five of the patients (65%) were male, 41 of them (35%) were female and their age average was 41. The mean operation time was 12 ± 4.8 min. VAS/satisfaction score was found as 2.2/4.3, 1.8/4.0, 1.2/4.4 respectively on the 3rd, 7th, and 21st days. Four of the patient (3.5%) had relapse. CONCLUSION: This technique is an easily applicable, cost efficient way of operation which increases patient satisfaction. PMID:25625005

  18. The role of multimodality imaging in percutaneous left atrial appendage suture ligation with the LARIAT device.

    PubMed

    Laura, Diana M; Chinitz, Larry A; Aizer, Anthony; Holmes, Douglas S; Benenstein, Ricardo; Freedberg, Robin S; Kim, Eugene E; Saric, Muhamed

    2014-07-01

    Atrial fibrillation (AF), the most common cardiac arrhythmia, is a significant cause of embolic stroke. Although systemic anticoagulation is the primary strategy for preventing the thromboembolic complications of AF, anticoagulants carry major bleeding risks, and many patients have contraindications to their use. Because thromboembolism typically arises from a clot in the left atrial appendage (LAA), local therapeutic alternatives to systemic anticoagulation involving surgical or percutaneous exclusion of the LAA have been developed. Surgical exclusion of the LAA is typically performed only as an adjunct to other cardiac surgeries, thus limiting the number of eligible patients. Furthermore, surgical exclusion of the LAA is frequently incomplete, and thromboembolism may still occur. Percutaneous LAA exclusion includes two approaches: transseptal delivery of an occlusion device to the LAA and epicardial suture ligation of the LAA, the LARIAT procedure. In the LARIAT procedure, a pretied snare is placed around the epicardial surface of the LAA orifice via pericardial access. Proper snare placement is achieved with epicardial and endocardial magnet-tipped guidewires. The endocardial wire is advanced transvenously to the LAA apex after transseptal puncture. The epicardial wire, introduced into the pericardial space, achieves end-to-end union with the endocardial wire at the LAA apex. The snare is then placed over the LAA, tightened, and sutured. On the basis of early clinical experience, the LARIAT procedure has a high success rate of LAA exclusion with low risk for complications. The authors describe the indispensable role of real-time transesophageal echocardiography in the guidance of LAA epicardial suture ligation with the LARIAT device.

  19. Cecal Ligation and Puncture Results in Long-Term Central Nervous System Myeloid Inflammation.

    PubMed

    Singer, Benjamin H; Newstead, Michael W; Zeng, Xianying; Cooke, Christopher L; Thompson, Robert C; Singer, Kanakadurga; Ghantasala, Ramya; Parent, Jack M; Murphy, Geoffrey G; Iwashyna, Theodore J; Standiford, Theodore J

    2016-01-01

    Survivors of sepsis often experience long-term cognitive and functional decline. Previous studies utilizing lipopolysaccharide injection and cecal ligation and puncture in rodent models of sepsis have demonstrated changes in depressive-like behavior and learning and memory after sepsis, as well as evidence of myeloid inflammation and cytokine expression in the brain, but the long-term course of neuroinflammation after sepsis remains unclear. Here, we utilize cecal ligation and puncture with greater than 80% survival as a model of sepsis. We found that sepsis survivor mice demonstrate deficits in extinction of conditioned fear, but no acquisition of fear conditioning, nearly two months after sepsis. These cognitive changes occur in the absence of neuronal loss or changes in synaptic density in the hippocampus. Sepsis also resulted in infiltration of monocytes and neutrophils into the CNS at least two weeks after sepsis in a CCR2 independent manner. Cellular inflammation is accompanied by long-term expression of pro-inflammatory cytokine and chemokine genes, including TNFα and CCR2 ligands, in whole brain homogenates. Gene expression analysis of microglia revealed that while microglia do express anti-microbial genes and damage-associated molecular pattern molecules of the S100A family of genes at least 2 weeks after sepsis, they do not express the cytokines observed in whole brain homogenates. Our results indicate that in a naturalistic model of infection, sepsis results in long-term neuroinflammation, and that this sustained inflammation is likely due to interactions among multiple cell types, including resident microglia and peripherally derived myeloid cells. PMID:26862765

  20. Comparison of two preclinical myocardial infarct models: coronary coil deployment versus surgical ligation

    PubMed Central

    2014-01-01

    Background Despite recent advances, myocardial infarction (MI) remains the leading cause of death worldwide. Pre-clinical animal models that closely mimic human MI are pivotal for a quick translation of research and swine have similarities in anatomy and physiology. Here, we compared coronary surgical ligation versus coil embolization MI models in swine. Methods Fifteen animals were randomly distributed to undergo surgical ligation (n = 7) or coil embolization (n = 8). We evaluated infarct size, scar fibrosis, inflammation, myocardial vascularization, and cardiac function by magnetic resonance imaging (MRI). Results Thirty-five days after MI, there were no differences between the models in infarct size (P = 0.53), left ventricular (LV) ejection fraction (P = 0.19), LV end systolic volume (P = 0.22), LV end diastolic volume (P = 0.84), and cardiac output (P = 0.89). Histologically, cardiac scars did not differ and the collagen content, collagen type I (I), collagen type III (III), and the I/III ratio were similar in both groups. Inflammation was assessed using specific anti-CD3 and anti-CD25 antibodies. There was similar activation of inflammation throughout the heart after coil embolization (P = 0.78); while, there were more activated lymphocytes in the infarcted myocardium in the surgical occlusion model (P = 0.02). Less myocardial vascularization in the infarction areas compared with the border and remote zones only in coil embolization animals was observed (P = 0.004 and P = 0.014, respectively). Conclusions Our results support that surgical occlusion and coil embolization MI models generate similar infarct size, cardiac function impairment, and myocardial fibrosis; although, inflammation and myocardial vascularization levels were closer to those found in humans when coil embolization was performed. PMID:24885652