Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Ligation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources

Secondary prophylaxis of esophageal variceal treatment: Endoscopic sclerotherapy, band ligation and combined therapy--long-term results.

BACKGROUND/AIMS: To evaluate the long-term results of endoscopic sclerotherapy and endoscopic band ligation in secondary prophylaxis on variceal eradication and to evaluate the effectiveness of endoscopic sclerotherapy and endoscopic band ligation combination in resistant cases. METHODS: The results of the patients who underwent endoscopic sclerotherapy (n=47 31M/16F, 49.9+/-16.1 years) and endoscopic band ligation (n=72 56M/16F, 46.6+/-14.1 years) were compared. The results of patients whose varices could not be eradicated who were treated with endoscopic band ligation and combined endoscopic sclerotherapy (combined group, n=62 49M/13F, 48.8+/-12.7 years) are also given. Patients were evaluated for portal hypertension etiology, Child score, fundal varices-portal hypertensive gastropathy presence according to first and last endoscopic findings, varices eradication, rebleeding, recurrence and complication rates. RESULTS: 181 patients were followed for 35.2+/- 25.6 (6-123) months. Varices eradication and recurrence rates were 93.6% and 44.7% for endoscopic sclerotherapy, and 90.3% and 47.2% for endoscopic band ligation (p>0.05). The number of sessions for eradication were 6.6+/-4.0 and 2.5+/-1.6 for endoscopic sclerotherapy and endoscopic band ligation groups, respectively (p<0.05). Rebleeding rates were 16.3% for endoscopic sclerotherapy and 6.1% for endoscopic band ligation (p>0.05). In the combined group, although the rebleeding rate was 34.4%, which was as expected significantly higher than that of endoscopic sclerotherapy and endoscopic band ligation, variceal eradication and the recurrence rates were 82.3% and 50.0%, similar to endoscopic sclerotherapy and endoscopic band ligation, and the number of sessions for eradication was 6.8+/-3.5. CONCLUSIONS: Endoscopic band ligation is the most suitable method for varices eradication, but there is a group of patients resistant to endoscopic band ligation. In this patient group, the addition of endoscopic sclerotherapy to endoscopic band ligation was a suitable and effective technique in order to achieve variceal eradication.

Adult↗

Tandem ligation of unprotected peptides through thiaprolyl and cysteinyl bonds in water.

Tandem ligation for the synthesis and modification of proteins entails forming two or more regiospecific amide bonds of multiple free peptide segments without a protecting-group scheme. We here describe a semi-orthogonal strategy for ligating three unprotected peptide segments, two of which contain N-terminal (NT) cysteine, to form in tandem two amide bonds, an Xaa-SPro (thiaproline), and then an Xaa-Cys. This strategy exploits the strong preference of an NT-cysteinyl peptide under acidic conditions to undergo selectively an SPro-imine ligation rather than a Cys-thioester ligation. Operationally, it was performed in the N --> C direction, first by an imine ligation at pH < 3 to afford an Xaa-thiazolidine ester bond between a peptide containing a carboxyl terminal (CT)-glycoaldehyde ester and a second peptide containing both an NT-Cys and a CT-thioester. The newly created O-ester-linked segment with a CT-thioester was then ligated to another NT-cysteinyl peptide through thioester ligation at pH > 7 to form an Xaa-Cys bond. Concurrently, this basic condition also catalyzed the O,N-acyl migration of an Xaa-thiazolidine ester to the Xaa-SPro bond at the first ligation site to complete the tandem three-segment ligation. Both ligation reactions were performed in aqueous buffered solvents. The effectiveness of this three-segment ligation strategy was tested in six peptides ranging from 19 to 70 amino acids, including thiaproline --> proline analogues of somatostatins and two CC-chemokines. The thiaproline replacements in these peptides and proteins did not result in altered biological activity. By eliminating the protecting-group scheme and coupling reagents, tandem ligation of multiple free peptide segments in aqueous solutions enhances the scope of protein synthesis and may provide a useful approach for combinatorial segment synthesis.

Amino Acid Sequence↗

Ligation of CD40 stimulates the induction of nitric-oxide synthase in microglial cells.

The present study was undertaken to investigate the role of CD40 ligation in the expression of inducible nitric-oxide synthase (iNOS) in mouse BV-2 microglial cells and primary microglia. Ligation of CD40 alone by either cross-linking antibodies against CD40 or a recombinant CD40 ligand (CD154) was unable to induce the production of NO in BV-2 microglial cells. The absence of induction of NO production by CD40 ligation alone even in CD40-overexpressed BV-2 microglial cells suggests that a signal transduced by the ligation of CD40 alone is not sufficient to induce NO production. However, CD40 ligation markedly stimulated interferon-gamma (IFN-gamma)-mediated NO production. Ligation of CD40 in CD40-overexpressed cells further stimulated IFN-gamma-induced production of NO. This stimulation of NO production was accompanied by stimulation of the iNOS protein and mRNA. In addition to BV-2 glial cells, CD40 ligation also stimulated IFN-gamma-mediated NO production in mouse primary microglia and peritoneal macrophages. To understand the mechanism of induction/stimulation of iNOS, we investigated the roles of nuclear factor kappaB (NF-kappaB) and CCAAT/enhancer-binding protein beta (C/EBPbeta), transcription factors responsible for the induction of iNOS. IFN-gamma alone was able to induce the activation of NF-kappaB as well as C/EBPbeta. However, CD40 ligation alone induced the activation of only NF-kappaB but not of C/EBPbeta, suggesting that the activation of NF-kappaB alone by CD40 ligation is not sufficient to induce the expression of iNOS and that the activation of C/EBPbeta is also necessary for the expression of iNOS. Consistently, dominant-negative mutants of p65 (Deltap65) and C/EBPbeta (DeltaC/EBPbeta) inhibited the expression of iNOS in BV-2 microglial cells that were stimulated with the combination of IFN-gamma and CD40 ligand. Stimulation of IFN-gamma-mediated activation of NF-kappaB but not of C/EBPbeta by CD40 ligation suggests that CD40 ligation stimulates the expression of iNOS in IFN-gamma-treated BV-2 microglial cells through the stimulation of NF-kappaB activation. This study illustrates a novel role for CD40 ligation in stimulating the expression of iNOS in microglial cells, which may participate in the pathogenesis of neuroinflammatory diseases.

Animals↗

Conventional vs. triple rubber band ligation for hemorrhoids. A prospective, randomized trial.

Two hundred five patients with symptomatic first- and second-degree hemorrhoids were randomized to receive either conventional rubber band ligation or triple rubber band ligation. In conventional rubber band ligation, the hemorrhoids were ligated at one primary site per session at intervals of four weeks until symptoms were relieved or when all three hemorrhoids were ligated. In triple rubber band ligation, all three primary hemorrhoids were ligated in a single session. After completion of treatment, the patients were examined every three months, or earlier if symptoms recurred. Both methods were effective in the treatment of early hemorrhoids and the incidence of postligation pain and complications was similar. The advantages of having the treatment completed at the initial visit in triple rubber band ligation are obvious. Furthermore, less treatment sessions were required for triple rubber band ligation to control symptoms than for conventional rubber band ligation. Triple rubber band ligation is more cost-effective and therefore is recommended.

Clinical Trials as Topic↗

Influence of ligation of the internal iliac veins on the venous plexuses around the sacrum.

Excessive bleeding is a significant problem during total sacrectomy. Ligation of the internal iliac veins to control bleeding from the pelvic venous plexus has been reported to be mandatory. However, despite ligation of the internal iliac veins, excessive hemorrhage from the pelvic and epidural venous plexuses is often encountered. We postulated that ligation of the internal iliac veins increases blood loss during total sacrectomy and we investigated the influence of ligation of the internal iliac veins on the pelvic and epidural venous plexuses in white rabbits. We also investigated the influence of the animal's operative position on the epidural venous pressure. Venography was performed to study the differences in blood flow patterns before and after ligation of the internal iliac veins. Without ligation, contrast medium passed into the inferior vena cava, but not into the epidural venous plexus. The epidural venous plexus was contrast-filled when the internal iliac veins were ligated. The pressure in the internal iliac veins was increased with their ligation, and decreased with ligation of the abdominal aorta. The pressure was also decreased with intentional bleeding from the epidural venous plexus, and with changing the animal's position to headdown. Ligation of the internal iliac veins leads to congestion of the pelvic venous and epidural venous plexuses. Ligation of the internal iliac arteries and positioning the animal headdown were effective ways to resolve the congestion in these venous plexuses.

Animals↗

Progressive secretory dysfunction in the rat submandibular gland after excretory duct ligation.

Unilateral ligation of the main excretory duct of the rat submandibular gland caused a progressive deterioration of secretory function characterized by: (1) the secretion of progressively smaller volumes of saliva in response to a standard maximal intraperitoneal (i.p.) dose of pilocarpine. Saliva volume was reduced 69.4, 88.8 and 95.9 per cent, respectively, 1, 3 and 7 days after duct ligation. By 2 weeks, the contralateral, non-ligated gland had an enhanced response to pilocarpine and the ligated gland a 96.8 per cent reduction in the volume of saliva secreted; (2) a progressive reduction in the maximum flow rates attained upon stimulation with pilocarpine, which were 23.4, 10.1 and 5.1 per cent of those attained in the contralateral gland at, respectively, 1, 3 and 7 days after ligation; (3) a progressive increase in the sodium concentrations of saliva, which became plasma-like 2 weeks after ligation; (4) a significantly reduced secretory response to standard doses of isoproterenol, phenylephrine, methoxamine and substance P 2 weeks after ligation. In addition, both cholinergic and adrenergic receptors were significantly reduced in number 2 weeks after ligation. Administration of daily injections of pilocarpine (10 mg, i.p.) after duct ligation reduced the gland atrophy observed 3 days (by 17 per cent) and 1 week (by 9 per cent) later, but did not prevent the reduction in volume or flow rats observed after duct ligation alone. Thus ligation of the main excretory duct causes a progressive dysfunction in acinar and duct cells in the rat submandibular gland and alters their responsiveness to physiological regulators of secretion. The alterations in glandular secretory function and in the composition of saliva which occur in diseases causing partial or complete obstruction to the flow of saliva are likely to be similar to the changes described.

Animals↗

Beta-catenin/sirtuin 1/farnesoid X receptor pathway promotion of portal vein ligation and parenchymal transection-induced rapid liver regeneration.

BACKGROUND: By accelerating the regeneration of the future liver remnant, portal vein ligation and parenchymal transection allows for more extensive hepatectomy. Given that the mechanism remains poorly understood, the aim of this study was to investigate the mechanism of portal vein ligation and parenchymal transection-induced liver regeneration. METHODS: A portal vein ligation and parenchymal transection-induced liver regeneration mouse model was established, followed by RNA microarray analysis to identify candidate molecules. Genomic deletion and chemical manipulation of target molecules were used to explore their functions in portal vein ligation and parenchymal transection-induced liver regeneration. Validation was conducted using a diseased liver model and human samples. RESULTS: Portal vein ligation and parenchymal transection-induced liver regeneration was significantly accelerated compared with that in sham-operated mice (P < .05). An RNA microarray revealed that Sirtuin 1 is a crucial molecule in the proliferation of the future liver remnant. Regardless of whether Sirtuin 1 is inhibited chemically or through genetic deletion, portal vein ligation and parenchymal transection-induced liver regeneration is distinctly attenuated. Further investigation revealed that Sirtuin 1 promoted portal vein ligation and parenchymal transection-induced liver regeneration via the farnesoid X receptor. In addition, beta-catenin also was found to participate in the process of future liver remnant proliferation. Chemical inhibition of beta-catenin markedly impaired but activation of WNT/beta-catenin mildly enhanced portal vein ligation and parenchymal transection-induced liver regeneration (P < .05). Deletion of Sirtuin 1 blocked the facilitating effect of beta-catenin on portal vein ligation and parenchymal transection-induced liver regeneration. These findings were validated in diseased liver models and patient samples, confirming the correlation between the beta-catenin/Sirtuin 1/farnesoid X receptor pathway and portal vein ligation and parenchymal transection-induced liver regeneration. CONCLUSION: Activation of the beta-catenin/Sirtuin 1/farnesoid X receptor pathway offers critical mechanistic insights into accelerating portal vein ligation and parenchymal transection-induced liver regeneration. Modulation of beta-catenin/Sirtuin 1/farnesoid X receptor may therefore improve clinical outcomes in patients receiving staged hepatectomy.

Liver Regeneration↗

Comparison of endoscopic ligation and propranolol for the primary prevention of variceal bleeding.

BACKGROUND AND METHODS: We compared propranolol therapy and endoscopic ligation for the primary prevention of bleeding from esophageal varices. This prospective, controlled trial included consecutive eligible patients who had large varices (>5 mm in diameter) that were at high risk for bleeding. The patients were assigned to either propranolol therapy, at a dose sufficient to decrease the base-line heart rate by 25 percent, or variceal ligation, to be performed weekly until the varices were obliterated or so reduced in size that it was not possible to continue treatment. RESULTS: Of the 89 patients, 82 of whom had cirrhosis of the liver, 44 received propranolol and 45 underwent variceal ligation. The mean (+/-SD) duration of follow-up in each group was 14+/-9 and 13+/-10 months, respectively. The mean time required to achieve an adequate reduction in the heart rate was 2.5+/-1.7 days; the mean number of sessions needed to complete variceal ligation was 3.2+/-1.1. After 18 months, the actuarial probability of bleeding was 43 percent in the propranolol group and 15 percent in the ligation group (P=0.04). Twelve patients in the propranolol group and four in the ligation group had bleeding. Three of the four in the ligation group had bleeding before their varices had been obliterated. Nine patients in the ligation group had recurrent varices, a mean of 3.7 months after the initial treatment. Five patients in each group died; bleeding from the varices was the cause of death of four patients in the propranolol group and of three in the ligation group. There were no serious complications of variceal ligation; in the propranolol group, treatment was stopped in two patients because of side effects. CONCLUSIONS: In patients with high-risk esophageal varices, endoscopic ligation of the varices is safe and more effective than propranolol for the primary prevention of variceal bleeding.

Adrenergic beta-Antagonists↗

Feasibility and potential benefit of maintenance endoscopic variceal ligation in patients with unresectable hepatocellular carcinoma and acute esophageal variceal hemorrhage: a controlled trial.

BACKGROUND: Patients with unresectable hepatoma and acute esophageal variceal bleeding have extremely high rates of recurrent bleeding and mortality. This controlled study evaluates the feasibility and potential benefit of maintenance endoscopic variceal ligation in these patients. METHODS: Patients with unresectable hepatoma and acute esophageal variceal bleeding underwent emergent endoscopic variceal ligation. After hemostasis, patients were randomized to undergo maintenance or esophageal variceal ligation (EVL) as necessary (demand ligation). RESULTS: Fifty-four patients underwent maintenance EVL and 55 demanded EVL. One or more subsequent EVL session could be performed in only 30 patients (55.6%) in the maintenance group (actual maintenance ligation). Logistic regression analysis found that hepatic function determines the feasibility of maintenance ligation (Child-Pugh's A+B vs. C, OR 23.00: 95% CI [5.26, 100.66]). The survival and recurrent bleeding rates were similar in both groups. A subgroup analysis of patients with Child-Pugh's A and B hepatic reserve in both the maintenance EVL group (n = 24) and demand EVL group (n = 25) was performed to assess the potential benefit of maintenance ligation. Maintenance ligation reduced the rate of recurrent bleeding compared with demand ligation (p = 0.043). Cox regression showed that portal vein thrombosis and tumors in both hepatic lobes were also factors together with EVL that determined recurrence of bleeding. Survival was similar in both groups. CONCLUSIONS: Maintenance ligation is feasible in patients with unresectable hepatoma and variceal hemorrhage if they have a good hepatic reserve. Maintenance ligation might lower the rate of recurrent bleeding in this subgroup of patients.

Acute Disease↗

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

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 homonymous and diagonal arteries. This animal model was comparable to the clinical situation.

Animals↗

Multiple hemorrhoidal ligation: a prospective, randomized trial evaluating a new technique.

PURPOSE: A modified anoscope was developed, with lateral apertures at the left lateral, right anterior, and right posterior quadrants, to enable synchronous exposure and ligation of all three internal hemorrhoids. Results were compared with those for conventional multiple ligation. METHODS: Postligation pain, complications, and outcomes were compared between synchronous ligation with the new anoscope (synchronous group) and three-quadrant ligation with a conventional anoscope with similar overall dimensions (conventional group). RESULTS: Twenty-five patients were prospectively randomized to each group. Postligation pain and analgesic requirements were recorded up to 28 days, and postligation complications and outcomes were evaluated for a minimum of 6 months. Narcotic requirements were lower in the synchronous group, but this difference did not achieve statistical significance (P > 0.05, Student's t-test). Secondary hemorrhage occurred in 1 patient (4 percent) in the conventional group but resolved spontaneously. The synchronous group experienced significantly less pain during the ligation procedure and for 2 days afterward (P < 0.01, Wilcoxon's test). External hemorrhoidal thrombosis developed in 4 percent of the synchronous group and 12 percent of conventionally treated patients, all of whom responded to conservative treatment. Repeat ligation was required less often in the synchronous group (16 percent) than with conventional ligation (28 percent). Surgery (completion hemorrhoidectomy for external thrombosis) was necessary in one patient (4 percent) in each group. Anal stenosis developed in one patient in the synchronous group. CONCLUSION: The new anoscope provides improved exposure of all three internal hemorrhoids and permits optimal placement of the rubber bands; this may account for the decreased postligation pain and lower repeat ligation rates. Synchronous hemorrhoidal ligation is a less painful method of multiple hemorrhoidal ligation and may improve outcomes compared with conventional multiple ligation.

Analgesics↗

Non-hydrostatic pulmonary edema after coronary artery ligation in dogs. Protective effect of indomethacin.

Pulmonary edema which develops during acute myocardial infarction is generally believed to result solely from pulmonary microvascular hypertension. However, patient with myocardial infarction and pulmonary edema occasionally are found to have normal pulmonary wedge pressure. We report data indicating that pulmonary edema develops after coronary artery ligation despite stable microvascular pressure. Four groups of open-chest dogs were studied: (1) nine dogs with left anterior descending coronary artery ligation, (2) seven dogs with sham coronary ligation, (3) seven dogs ligated after beginning an infusion of indomethacin (5 mg/kg per hr), and (4) five dogs ligated after an infusion of the drug's vehicle was begun. Extravascular lung water and pulmonary blood volume were measured at hourly intervals during the 2 hours before and after coronary ligation or sham ligation. Gravimetric lung water was measured immediately thereafter. Changes of net pulmonary intravascular driving force (the difference of microvascular hydrostatic and oncotic pressure) after ligation or sham ligation were small and comparable in all groups. Pulmonary blood volume did not change in any group. Pulmonary extravascular water volume remained constant in the sham group but rose significantly in the ligated group. Gravimetric lung water also was significantly higher in the latter group. We interpret these results to indicate that factors other than microvascular pressure can mediate the formation of these results to indicated that factors other than microvascular pressure can mediate the formation of edema during acute myocardial infarction; increased pulmonary microvascular permeability may be responsible. Indomethacin infusion blocked the formation of edema after coronary ligation, even though net microvascular driving force was highest in this group. Infusion of the vehicle alone did not prevent edema. The mechanism by which indomethacin exerts this protective effect is unclear but is probably a result of its inhibition of cyclo-oxygenase or cyclic nucleotide phosphodiesterase.

Animals↗

Comparison of myocardial infarction with sequential ligation of the left anterior descending artery and its diagonal branch in dogs and sheep.

We report a comparison of the effects of myocardial infarction in dogs and sheep using sequential ligation of the left anterior descending artery (LAD) and its diagonal branch (DA), with hemodynamic, ultrasonographic and pathological evaluations. Five animals were used in each group. After surgical preparation, the LAD was ligated at a point approximately 40% of the distance from the apex to the base of the heart, and after one hour, the DA was ligated at the same level. Hemodynamic and ultrasonographic measurements were performed preligation, 30 minutes after LAD ligation, and 1 hour after DA ligation. As a control, two animals in each group were used for the simultaneous ligation of the LAD and the DA. Two months after the coronary ligation, the animals were evaluated as previously, and killed for postmortem examination of their hearts. All seven animals in the dog group survived the experimental procedures, while in the sheep group only animals with sequential ligation of the LAD and DA survived. Statistically significant decreases in systemic arterial blood pressure and cardiac output, and an increase in the pulmonary artery capillary wedge pressure (PACWP) were observed one hour after sequential ligation of the LAD and its DA in the sheep, while only systemic arterial pressures decreased in the dog. Ultrasonographic analyses demonstrated variable degrees of anteroseptal dyskinesia and akinesia in all sheep, but in no dogs. Data two months after coronary artery ligation showed significant increases in central venous pressure, pulmonary artery pressure, and PACWP in the sheep, but not in the dog. Left ventricular end-diastolic dimension and left ventricular end-systolic dimension in ultrasonographic studies were also increased only in the sheep. Pathologically, the well-demarcated thin-walled transmural anteroseptal infarcts with chamber enlargement were clearly seen in all specimens of sheep, and only-mild-to-moderate chamber enlargements with endocardial fibrosis were observed in the dog hearts. In conclusion, this study confirms that the dog is not a suitable model for myocardial infarction with failure by coronary artery ligation despite negligent operative mortality, when compared directly with an ovine model.

Animals↗

The effects of splenic artery ligation in an experimental model of secondary hypersplenism.

OBJECTIVE: To induce hypersplenism in rats by splenic vein ligation and to investigate the effects of splenic artery ligation in this model. BACKGROUND: Selective arterial embolisation and splenic artery ligation (SAL) are used in the treatment of secondary hypersplenism in some medical centres but these methods are not common. MATERIALS AND METHODS: Thirty male Saprague-Dawley rats were allocated to three groups (n = 10). The first group underwent laparotomy, the second and third groups underwent laparotomy and splenic vein ligation. At the end of the third week, laparotomy was performed in the first and second groups and splenic artery ligation in the third group. Erythrocyte, leukocyte and platelet counts were performed weekly. At the end of the sixth week, the animals were sacrificed and the spleens were taken for histopathologic examination. RESULTS: In the second and third groups, after splenic vein ligation, the erythrocyte and platelet counts were significantly reduced at the end of the second week (p < 0.01). In the second group, which underwent splenic vein ligation only, the levels remained low throughout the experiment. In the third group, after splenic artery ligation, there were rises in both erythrocyte and platelet counts; the levels were similar to the levels in the control group at three weeks after splenic artery ligation (p > 0.05). No significant changes were observed in the leukocyte counts throughout the experiment (p > 0.05). CONCLUSIONS: Splenic vein ligation successfully induces experimental secondary hypersplenism. This state can be ameliorated by splenic artery ligation.

Animals↗

Sequential changes of gastric hyperplastic polyps following endoscopic ligation.

BACKGROUND: Endoscopic ligation has been extensively applied in the management of esophageal and gastric varices with or without bleeding. The varices are automatically eradicated through the use of ligation. However, whether avascular necrosis will occur in a gastrointestinal polyp when the base is ligated remains unclear. The aims of this pilot study were to investigate the sequential changes of gastric hyperplastic polyps following endoscopic detachable snare ligation and to determine the possibility of induction of avascular necrosis in these lesions following ligation. METHODS: Eleven patients with eighteen gastric hyperplastic polyps were treated with endoscopic detachable-snare ligation. The polyps were observed for 5 minutes and biopsies were then conducted. At 14 days after endoscopic ligation, follow-up endoscopies were performed to assess the outcome of the strangulated polyps. RESULTS: After being strangulated by the detachable snares, a majority of the polyps immediately congested (94%), and then developed cyanotic change (89%) approximately 4 minutes later. Pathological examination revealed severe venous congestion in the lamina propria of the strangulated polyps. On follow-up endoscopy 2 weeks later, all the snares had dropped off, and avascular necrosis occurred in sixteen polyps (89%). All of the polyps with avascular necrosis were detected to have developed cyanotic changes in initial endoscopy. No complications occurred during or following the ligation procedure. CONCLUSIONS: Most gastric hyperplastic polyps develop avascular necrosis following ligation by detachable snare. Cyanotic change is an important predictor of the outcomes of the lesions following endoscopic ligation. The application of this ligation technique in treatment of bleeding or non-bleeding gastrointestinal polyps deserves further investigation.

Adolescent↗

[Cardiac hemodynamics after suprarenal ligation of the inferior vena cava and the resection of the right kidney or injection of ligustrazine in rats].

BACKGROUND & OBJECTIVE: Primary retroperitioneal tumor often invades large vessels; the difficulty of operation is the management of the vessels, especially the inferior vena cava (IVC). The suprarenal ligation of the IVC was considered to be dangerous. The aim of this study was to investigate the cardiac hemodynamics following suprarenal ligation of the IVC and the resection of the right kidney or injection of ligustrazine in rats, and to provide theories and guides for the clinical operations. METHODS: The rats were divided into six groups of seven. The groups were control group, false operation group, suprarenal ligation of the IVC group, suprarenal ligation of IVC and resection of right kidney group, ligustrazine group, and placebo group. All rats were determined for heart rate, ejection fraction, cardiac output, stroke volume, arterial pressure at 1st, 6th, 24th, 48th hour after the operations. RESULTS: The indexes of the false operation group had no change. CO(0.018+/-0.002 L/min), SV(0.054+/-0.008 ml), AP(H)(173+/-12 mmHg), AP(L)(161+/-11 mmHg) decreased to the lowest point at 1st hour following the suprarenal ligation of the IVC, but compensated completely at 48th hour after the operation. All rats in this group survived during the study period. CO(0.012+/-0.002 L/min), SV(0.038+/-0.005 ml), AP(H)(138+/-8 mmHg), AP(L)(131+/-9 mmHg)decreased to the lowest point at 1st hour following the suprarenal ligation of the IVC and resection of the right kidney, CO and SV were not compensated completely at 48th hour after the operation, two rats died in this group. CO (0.025+/-0.004 L/min), SV(0.063+/-0.009 ml), AP(H)(190+/-14 mmHg), AP(L)(163+/-9 mmHg)decreased to the lowest point at 1st hour following the suprarenal ligation of the IVC, but compensated quickly at 24th hour after the operation, all rats survived in this group. The placebo group, compared with the ligustrazine group, had no obvious change. CONCLUSION: Cardiac function was affected by low returned blood volume following the suprarenal ligation of the IVC, but compensated completely at 48th hour after the operation. The suprarenal ligation of the IVC and injection of ligustrazine could improve cardiac function of the experimental rats. The suprarenal ligation of the IVC and resection of the right kidney, which not only increased the operative difficulty but also reduced cardiac functional compensation and appeared the death of rats, were not appropriate. We suggest to ligate the suprarenal IVC and to inject ligustrazine after resecting the tumor and infiltrated IVC, not to resect normal right kidney. To infuse solution by upper limb to increase returned blood volume in early phase after the operation.

Animals↗

[Development of a multiple ligator and its endoscopic therapy for patients with esophageal varices].

The ligators we have developed is a kind of economical and effective six-ring ligator. Endoscopic variceal ligation (EVL) was performed to treat bleeding from esophageal varices in patients with liver cirrhosis using self-made ligator and foreign multiple ligator. There are similar effects with both self-made ligator and foreign mutiple ligator in the control of variceal bleeding, variceal obliteration and rebleeding (93.8%, 87.5%, 0 in the group with self-made ligator, 94.5%, 87.1%, 2.4% in the group with foreign multiple ligator, P>0.05). In terms of the quality index, successful operation rate, hemastatic rate, variceal obliteration rate, rebleeding rate, complications and variceal recurrence rate, the self-made ligator is as good as the foreign multiple ligator, but much cheaper.

Adolescent↗

[Effects on the mouse epididymis of juvenile ligation of the ductuli efferentes or proximal epididymal duct: qualitative and quantitative histological studies (author's transl)].

The ductuli efferentes or the epididymal duct between the head and body were ligated in young mice aged 20-30 days, and effects of the ligation on the epididymis were histologically examined by means of qualitative and quantitative procedures at the age of 50-60 days. As reported previously (Takano, 1980), the epididymal duct of the mouse can be divided into five regions (regions I-V). On the morphometric basis, the five regions can be divided into two major portions, proximal and distal. The proximal portion consists of regions I, II and III which form the head of the epididymis. The distal portion is composed of regions IV and V which form the body and tail of the organ. The results of the qualitative and quantitative analysis in the previous study suggested that the proximal portion is functionally related with maturation of sperms and the distal portion is concerned with storage of sperms. Juvenile ligation of the ductuli efferentes or the epididymal duct between the proximal and distal portions caused the following changes in the epididymal duct. 1. Region I, "initial segment", was normally characterized by the lining of high columnar epithelial cells. Juvenile ligation of the ductuli efferentes impaired differentiation of region I, but not that of the remaining regions. Epididymal duct ligation between regions III and IV, on the other hand, exerted no influence on differentiation of the entire duct. Thus differentiation of region I is dependent upon the luminal contents transferred from the testis. 2. The luminal contents were stored in abundance in the distal portion after ligation of the ductuli efferentes, as were in the case of the normal control. On the other hand, the luminal contents were abundant in th proximal portion and scanty in the distal portion after epididymal duct ligation between the proximal and distal portions. These results suggest that the luminal contents may be produced in the proximal portion even after ligation of the ductuli efferentes, transported into the distal portion and stored there. 3. In region IV, the epithelium showed marked histological changes after ligation of the ductuli efferentes or the epididymal duct between regions III and IV. After ligation of the ductuli efferentes, PAS-positive granules and masses frequently appeared in the epithelial cells. After epididymal duct ligation between regions III and IV, clear vacuolated cells and large vacuole-like spaces frequently appeared within the epithelium. Thus it is likely that the epithelial cells of region IV are functionally related to the luminal contents stored.

Alkaline Phosphatase↗