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R Jakobs

Publications and source records attributed to R Jakobs.

89 records · Page 5Linked to original sources
PubMed1997

Fluoroscopically guided laser lithotripsy versus extracorporeal shock wave lithotripsy for retained bile duct stones: a prospective randomised study.

BACKGROUND AND AIMS: To compare extracorporeal shock wave lithotripsy (ESWL) and laser induced shock wave lithotripsy (LISL) of retained bile duct stones to stone free rate, number of therapeutic sessions, and costs. PATIENTS: Thirty four patients were randomly assigned to either ESWL or LISL therapy. The main reasons for failure of standard endoscopy were due to stone impaction (n = 12), biliary stricture (n = 8), or large stone diameter (n = 14). METHODS: An extracorporeal piezoelectic lithotripter with ultrasonic guidance and a rhodamine 6G laser with an integrated stone tissue detection system were used. LISL was performed exclusively under radiological control. RESULTS: Using the initial methods complete stone fragmentation was achieved in nine of 17 patients (52.4%) of the ESWL group and in 14 of 17 patients (82.4%) in the LISL group, or combined with additional fragmentation techniques 31 of the 34 patients (91.2%) were stone free at the end of treatment. In comparison LISL tended to be more efficient in clearing the bile ducts (p = 0.07, NS). Significantly less fragmentation sessions (1.29 v 2.82; p = 0.0001) and less additional endoscopic sessions (0.65 v 1.6; p = 0.002) were necessary in the LISL group. There were no major complications in either procedure. CONCLUSIONS: Compared with ESWL, fluoroscopically guided LISL achieves stone disintegration more rapidly and with significantly less treatment sessions, which leads to a significant reduction in cost.

Adult↗
PubMed1997

Management of esophageal perforations after therapeutic upper gastrointestinal endoscopy.

BACKGROUND: Esophageal perforation is one of the most dreaded complications in therapeutic gastrointestinal endoscopy. We assessed the frequency of esophageal perforation after endoscopic procedures in a highly specialized endoscopy unit and compared clinical outcomes in patients undergoing either surgical or conservative management. METHODS: From January 1985 to June 1996, 1011 instrumental endoscopic procedures (dilatation and bougienage) were performed in our department. The computerized complication database was searched to identify all patients with esophageal perforation during this same period, and their records were reviewed. RESULTS: Seventeen esophageal perforations (1.7%) occurred in the course of 1011 procedures. Four perforations resulted from balloon dilatation, and 13 were secondary to bougienage. Six patients were managed surgically (35%), all of them recovering uneventfully. Eleven patients were managed conservatively, mainly because they were unfit for surgery. Survival rate in this group was 82%; only two patients died, both of whom had underlying malignant disease. CONCLUSIONS: The current concept in management of esophageal perforations comprises surgical as well as medical treatment. In well-selected cases, non-operative treatment can be considered with favorable results.

Aged↗
PubMed1996

Homo-oligomerization domains in the lethal(2)giant larvae tumor suppressor protein, p127 of Drosophila.

The p127 tumor suppressor protein encoded by the lethal(2)giant larvae, l(2)gl, gene of Drosophila melanogaster forms high molecular mass complexes consisting predominantly of p127 molecules. To determine whether p127 can self-assemble in the absence of other binding factors, we analyzed the size of in vitro synthesized p127 by gel filtration and found that p127 is always recovered in a high molecular mass form, demonstrating that p127 can oligomerize on its own. Previous studies have revealed that p127 may contain three homo-oligomerization domains. To more accurately delineate these domains, we have generated a series of 32 chimaeric proteins made of defined portions of p127 fused to protein A, which behaves as a monomeric protein, and determined the level of oligomerization of the fused proteins. This study allowed us to map three discrete homo-oligomerization domains, each of approximately 50 amino acid residues in length. These domains, designated as HD-I, HD-II and HD-III, are located between amino acid residues 160 and 204, 247 and 298, and 706 and 749, respectively. Further analysis showed that the HD-I and HD-II domains can bind to themselves and to each other. We also mapped a domain in p127 between amino acid residues 377 and 438, which strongly reduces the degree of multimerization of chimaeric proteins containing HD-I and/or HD-II. Electron microscopy examination of negatively stained chimaeric proteins showed that protein A fused with either the domain HD-II or the domain HD-III forms discrete structures consistent with the formation of quaternary complexes, whereas protein A fused to a non-self binding domain of p127 appeared monomeric. Our results indicate that p127 alone is able to build quaternary structures forming a network with which other proteins associate. As revealed by the tumorous phenotype resulting from the inactivation of the l(2)gl gene, the organization of the p127 network and its association with other proteins play critical roles in the control of cell proliferation.

Amino Acid Sequence↗
PubMed1996

Management of retained bile duct stones: a prospective open trial comparing extracorporeal and intracorporeal lithotripsy.

BACKGROUND: Endoscopic management of common bile duct stones has become the approach of choice, especially in patients with high surgical risk. Problems are encountered if there are large stones or a duct stenosis. For these difficult stones, shock wave technology serves as an alternative to surgical intervention. METHODS: A total of 125 patients with common bile duct stones in whom conventional endoscopic treatment had failed were selected and treated either by extracorporeal piezoelectric lithotripsy (ESWL, n = 79) or intracorporeal electrohydraulic lithotripsy (EHL, n = 46). The average age of our patients was 70 years. RESULTS: In the ESWL group visualization of the stones by ultrasound and ensuing treatment were possible in 71 out of 79 patients (90%); stones could be fragmented in 68 patients. The biliary tree could then be completely freed of calculi in 62 of 79 patients, a success rate of 78.5%. In the EHL group, stones were successfully fragmented in 38 of 46 patients; 34 patients (74%) eventually became stone free. Thirty-day mortality was zero in both groups. Combined treatment including ESWL, EHL, and intracorporeal laser lithotripsy was finally successful in 118 patients (94%). CONCLUSIONS: Endoscopic management in combination with the lithotripsy techniques described can be recommended as the method of choice for treating difficult common bile duct stones. A success rate of almost 100% and a mortality rate of 0% is now the established standard, even in elderly and unstable patients.

Aged↗
PubMed1996

Peroral laser lithotripsy of difficult intrahepatic and extrahepatic bile duct stones: laser effectiveness using an automatic stone-tissue discrimination system.

OBJECTIVES: The use of laser lithotripsy with an integrated stone-tissue discrimination system is an ambitious treatment modality for bile duct stone fragmentation. The aim of our prospective study was to determine the effectiveness and safety of the laser system and to find whether it reduced the need for choledochoscopy. METHODS: Thirty patients with complicated bile duct stones were treated perorally with a flashlamp-pulsed Rhodamine-6G dye laser and an automatic stone-tissue discrimination system. Initial treatment sessions were performed under fluoroscopic guidance in each patient and switched to choledochoscopic control if the stone could not be approached properly. RESULTS: Eighteen of 19 patients with extrahepatic bile stones were treated under fluoroscopic control; 17 of 19 patients were successfully treated through laser therapy. In nine of the patients with intrahepatic stones (n = 11), choledochoscopy was necessary for sufficient laser lithotripsy; seven of those patients became stone-free. Twenty-four of 30 patients (80%) were stone-free after sole laser therapy. Combined with other methods, the overall success rate was 27/30 (90%). Therapy-related mortality was 0%. CONCLUSIONS: Laser lithotripsy is effective and safe. The stone-tissue discrimination system facilitates therapy under fluoroscopic control and precludes the need for choledochoscopy, which is highly significant (p <0.001) if the calculi are extrahepatically located.

Adult↗
PubMed1996

Endoscopic biliary stenting for the palliation of pancreatic cancer: results, survival predictive factors, and comparison of 10-French with 11.5-French gauge stents.

OBJECTIVES: To compare the efficacy and complications of different stent lengths and diameters in the palliation of jaundice caused by pancreatic cancer, as well as investigate survival predictive factors and the success of endoscopic therapy. METHODS: This study summarizes our results with 103 pancreas cancer patients treated by endoscopic plastic biliary stenting, of whom 87 were followed up until death or the time of writing. Before therapy, bilirubinemia, tumor primary size, presence of distant metastases, and signs of duodenal involvement were evaluated as prognosis risk factors. In a retrospective, nonrandomized fashion, we compared the efficacy and complications (especially clogging) of 10-French versus 11.5-French gauge stents and of "short" (< or = 8 cm) versus "long" (> or = 9 cm) prostheses. RESULTS: Thirty six men and 51 women (median age 74 yr) with pancreatic cancer were analyzed. Stenting could abolish jaundice or make it imperceptible (bilirubinemia < 3 mg %) in 74 patients (85%). Median bilirubinemia after treatment decreased from 13.9 mg/dl to 1.0 mg/dl. Hospital mortality was 2.7%. The commonest long term complication was clogging, which occurred 66 times in 33 patients. Median stent patency was 3 and 4 months for 10-F gauge and 11.5-F gauge stents, respectively (p > 0.05). When analyzing the patients who were alive 6 months after therapy, the clogging rate was 46% and 55% for 10-F and 11.5-F stents, respectively (p > 0.05). The length also did not influence stent patency. The only risk factor assessed before therapy, which independently predicted survival, was the presence of distant metastases. Median survival for patients with metastatic disease was 2.5 months and 9 months for those without metastases (p = 0.0015). CONCLUSIONS: We conclude that 10-F and 11.5-F stents have the same efficacy in the palliative management of malignant obstructive jaundice due to cancer of the pancreas. Detection of distant metastases is the best outcome predictive factor in these patients and should be regarded as a restriction to the insertion of biliary metal stents.

Adenocarcinoma↗
PubMed1995

[Ultrasound-guided extracorporeal piezoelectric lithotripsy of bile duct calculi].

AIM: Extracorporeal shock-wave lithotripsy (ESWL) with underwater spark discharge and stone localisation via x-ray has become established in the treatment of difficult bile duct stones. First results with the piezoelectric lithotripter (EPL) in our department have also been promising. METHOD: Between 1989 and 1993 we were able to treat 79 patients (mean age 76 years) with problematic bile duct stones with the EPL. Twenty-seven patients had solitary stones, 52 patients presented with multiple stones. Seventy-one patients received a nasobiliary tube to decompress the biliary system. For extracorporeal lithotripsy, we used a piezoelectric lithotripter (Piezolith 2300, R. Wolf, Knittlingen, Germany). RESULTS: Visualisation of the stones by ultrasound and ensuing treatment were possible in 71 out of 79 patients (90%), and complete stone removal was achieved in 62 patients (78.5%) after 7,595 shock-waves were applied per patient on average. In 55 patients, endoscopic extraction of fragments was performed to avoid fragment complications. Nearly all patients in whom extracorporeal lithotripsy failed were cleared of their stones by additional use of intracorporeal electrohydraulic lithotripsy. Three patients received palliatively an endoprosthesis and two patients were referred to surgery. CONCLUSION: EPL with sonographic stone localisation and mild sedo-analgesia is a valuable adjunct in the treatment of difficult biliary tract calculi. It is a worthwhile alternative especially for elderly patients who would be at high risk on general anaesthesia.

Aged↗
PubMed1994

Fluoroscopically guided laser lithotripsy of a pancreatic duct stone.

A 54-year-old man with early stage chronic pancreatitis and an impacted ductal stone in the pancreatic head complicated by a 2 cm abscess was treated with pulsed dye laser lithotripsy using an automatic stone tissue differentiation system under fluoroscopic control. This system automatically switches off the laser on contact with tissue. The 0.25 mm quartz fiber introduced into the pancreatic duct via a 5 French teflon catheter delivered 165 out of 1000 pulses at contact with the stone (100 mJ, 10 Hz). Partial stone disintegration was achieved making mechanical stone removal possible which initially failed. No major side-effect occurred. This new laser with a stone detection system seems to render fluoroscopically guided laser lithotripsy in the pancreatic duct safer thus warranting further clinical trials.

Calculi↗
PubMed1994

The Drosophila lethal(2)giant larvae tumor suppressor protein forms homo-oligomers and is associated with nonmuscle myosin II heavy chain.

Inactivation of the Drosophila lethal(2)giant larvae (l(2)gl) gene causes malignant tumors in the brain and the imaginal discs and produces developmental abnormalities in other tissues, including the germline, the ring gland and the salivary glands. Our investigations into the l(2)gl function have revealed that the gene product, or p127 protein, acts as a cytoskeletal protein distributed in both the cytoplasm and on the inner face of lateral cell membranes in a number of tissues throughout development. To determine whether p127 can form oligomers or can stably interact with other proteins we have analyzed the structure of the cytosolic form of p127. Using gel filtration and immunoaffinity chromatography we found that p127 is consistently recovered as high molecular weight complexes that contain predominantly p127 and at least ten additional proteins. Blot overlay assays indicated that p127 can form homo-oligomers and the use of a series of chimaeric proteins made of segments of p127 fused to protein A, which alone behaves as a monomer, showed that p127 contains at least three distinct domains contributing to its homo-oligomerization. Among the proteins separated from the immuno-purified p127 complexes or isolated by virtue of their affinity to p127, we identified one of the proteins by microsequencing as nonmuscle myosin II heavy chain. Further blot overlay assay showed that p127 can directly interact with nonmuscle myosin II. These findings confirm that p127 is a component of a cytoskeletal network including myosin and suggest that the neoplastic transformation resulting from l(2)gl gene inactivation may be caused by the partial disruption of this network.

Amino Acid Sequence↗
PubMed1994

[Axial hiatal hernia--correlation of motility disorders and pathological reflux in the esophagus in patients with and without reflux esophagitis].

Hiatal hernia is a very common finding in esophagogastroduodenoscopy (EGD). Only some patients with hiatal hernia suffer from gastroesophageal reflux disease (GERD), defined by pathological 24-h-pH-metry, while almost all patients with GERD do have hiatal hernia. To work out the differences in possible motility disorders and in a pathologic acid reflux we examined 92 patients with hiatal hernia by means of manometry and 24-h-pH-metry of the esophagus. A motility disorder of the tubular esophagus in the patients with GERD (with or without reflux esophagitis) was significantly more common than in patients without GERD (p = 0.006). In most cases it was an esophageal hypomotility. There is no significant difference in the basal pressure of the lower esophageal sphincter (LES) between the two groups. We conclude that besides other factors which impair esophageal clearance function a motility disorder of the tubular esophagus is the main cause for the development of GERD in the patients with hiatal hernia. A lowered pressure of the LES seems not to play a major role in the etiology of reflux esophagitis.

Adult↗
PubMed1993

[Extracorporeal piezoelectric lithotripsy of intra- and extrahepatic bile duct stones].

64 patients (27 men, 37 women; mean age 71 [27-90] years) with intra- or extrahepatic biliary stones, which could not be extracted endoscopically, underwent extracorporeal piezoelectric shock-wave lithotripsy (ESWL). The piezoelectric lithotripter which was used localizes the stones sonographically and the shock-waves are produced by a self-focusing sound generator consisting of 3,000 ceramic elements. The sonographic localization of the stones was successful in 57 patients (89%) and complete removal of stones was achieved in 49 (77%), after an average of 7,595 (1,000-30,800) shock-waves per patient. Spontaneous elimination of stone fragments occurred in 7 patients, while in 42 further endoscopic procedures (balloon catheter, Dormia basket, mechanical lithotripsy) were needed to remove stone fragments from the biliary tract. The only severe complication was cholangitis in two cases. It probably resulted from the associated lysis treatment. There was no case of pancreatitis and no death at 30 days. These data indicate that piezoelectric ESWL with sonographic stone localization is an effective method with few side effects for treating problematic biliary tract stones.

Adult↗
PubMed1992

[Hemosuccus pancreaticus due to a pressure ulcer in pancreatolithiasis].

Ultrasound examination in a 32-year-old man with epigastric pain and slightly elevated serum amylase level (66 U/l) revealed cysts in the head and tail of the pancreas as well as nonhomogeneous pancreas parenchyma as signs of chronic pancreatitis. Endoscopic retrograde cholangiopancreatography (ERCP) additionally showed pancreatolithiasis. Melena occurred 7 months later, haemoglobin concentration decreasing to 8.7 g/dl. Endoscopy revealed bleeding into the duodenum via the papilla major. Angiography excluded vessel rupture. Haemostasis was achieved by occlusion of the pancreatic duct with fibrin glue, but the procedure had to be repeated twice within the next 8 months. Three months later ERCP was performed because of melena with massive haematemesis (haemoglobin level 6.5 g/dl). Stones were no longer demonstrated. At the previous location a pressure ulcer was now demonstrated, together with fresh blood in the pancreatic duct. After the stones had passed the ulcer healed and the patient has been symptom-free for over 13 months.

Adult↗
PubMedDate not supplied

The role of serum liver enzymes in the diagnosis of choledocholithiasis.

BACKGROUND/AIMS: The introduction of laparoscopic cholecystectomy has increased the need for preoperative diagnosis of common bile duct stones. The purpose of this study is to verify the sensitivity of the liver function tests in the detection of duct stones. METHODOLOGY: We evaluated 438 patients (223 retrospectively and 215 prospectively) who underwent endoscopic papillotomy for bile duct stones in two different services. In every case, blood samples for liver function tests levels were collected prior to endoscopic retrograde cholangiopancreatography. RESULTS: The most sensitive test was gamma-glutamyl transpeptidase, that was abnormal in 92.2% of the cases. Alkaline phosphatase was elevated in 74.7% of the patients with choledocholithiasis. The least sensitive parameter was AST, altered in only 50.8% of times. The sensitivity of all liver tests for the diagnosis of choledochal stones taken together was 94.3%. CONCLUSIONS: Liver function tests are very sensitive in the detection of common bile duct stones, however these blood tests are in the normal range of about 5% of endoscopically treated patients.

Adolescent↗
PubMedDate not supplied

Spontaneous internal drainage of a pancreatic pseudocyst: a case report.

A 72 year old patient was admitted to our department with progressive abdominal symptoms caused by chronic pancreatitis. Physical examination and laboratory data were unremarkable, ultrasound showed a cystic lesion beneath the pancreatic head. Initial endoscopic examination demonstrated a duodenal stenosis; in the second examination the stenosis had resolved by spontaneous perforation of the pseudocyst into the duodenal bulb. Pancreatic and peri-pancreatic pseudocysts are common in acute and chronic pancreatitis; the frequency of their diagnosis increased following the advent of ultrasonography and computed tomography as diagnostic tools and more intensive clinical monitoring. Our knowledge about the incidental course of the disease is still limited. When the diagnosis is established, a lot of questions referring to the choice of therapeutic regime-conservative treatment, percutaneous intervention, endoscopic or surgical procedures arise. Therapeutic possibilities and their advantages are discussed.

Aged↗
PubMedDate not supplied

Endoscopic stenting in obstructive jaundice due to liver metastases: does it have a benefit for the patient?

BACKGROUND/AIMS: The goal of this report is to describe our experience with the palliative endoscopic treatment of jaundice occurring in the setting of liver and hilar metastases of a distant primary malignancy. MATERIAL AND METHODS: We retrospectively analyzed the clinical course of 29 consecutive patients with metastatic tumors not originating in the hepatobiliopancreatic area, who were treated by endoscopic retrograde cholangiopancreatography with endoprostheses insertion. RESULTS: We achieved a complete follow-up in 24 out of the 29 patients (11 women, median age 69 years). The primary tumor site was the colorectum in 15 patients, stomach in 4, lung in 2, breast and prostate in 1 and one patient had a lymphoma. The median bilirubinemia before therapy was 16 (1.8-31) mg/dl and the median minimum serum bilirubin reached after stenting was 2.6 (0.3-11.5) mg/dl. Stent dysfunction was observed in 33.5% of the patients and stent change was necessary 13 times. The median survival after therapy was 4 (2.5-19) months for patients with colon tumors and 3 (0.5-12) months in patients with other cancers. An improvement in the quality of life was obtained in 75% of the patients after endoscopic treatment. CONCLUSIONS: Endoscopic stenting should be attempted even on patients with obstructive jaundice due to liver metastases.

Aged↗
PubMedDate not supplied

[Endoscopic laser lithotripsy for difficult calculi after unsuccessful extracorporeal shock wave lithotripsy].

INTRODUCTION: More than 97% of common bile duct stones can be successfully managed by endoscopic papillotomy, mechanical lithotripsy and extracorporeal shock-wave lithotripsy. In this study, we evaluate the role of laser lithotripsy after failure of the above mentioned endoscopic methods. PATIENTS AND METHODS: Eighteen patients (15F, 3M; median age = 69 (28-83) years) were treated by endoscopic laser lithotripsy after ESWL failure. We employed a Rhodamine-6 G laser with a stone-tissue recognizing system. The laser fibers were cholangioscopically (direct vision) or blindly (under plain fluoroscopic control) placed. RESULTS: Seventeen patients were treated endoscopically and one was successfully managed percutaneously after failure of the transpapillary approach. Fourteen (78%) were stone-free after a mean of 1.56 laser therapy sessions alone. Two additional patients were successfully managed after partial fragmentation with combined treatment (mechanical lithotripsy: n = 1, electrohydraulic lithotripsy: n = 1). Overall, 89% of the patients were freed from their calculi. Cholangitis occurred once and the mortality was zero. CONCLUSIONS: We conclude that laser lithotripsy is an effective and safe treatment alternative in a highly selected patient population with difficult bile duct stones and considerable surgical risk.

Adult↗