Endotherapy of Zenker's diverticulum using the needle-knife technique: long-term follow-up

BACKGROUND AND STUDY AIMS

Endotherapy of Zenker's diverticulum by mucomyotomy of the bridge between the diverticulum and the esophageal lumen has been introduced as a promising alternative to surgical techniques. However the data on long-term clinical outcome are limited. After poor results in four patients treated by argon plasma coagulation, we studied the efficacy and the long-term outcome of dissection using a needle-knife in a consecutive series of patients.

PATIENTS AND METHODS

Between December 2001 and November 2004, 31 consecutively treated symptomatic patients (18 men; median age 69 years; range 52-92) with Zenker's diverticulum were enrolled into this retrospective study. In all cases mucomyotomy was performed with a needle-knife with the patient under conscious sedation. The procedure was repeated in the case of incomplete relief from dysphagia or of recurrent symptoms during follow-up. All patients completed questionnaires on the frequency and severity of dysphagia, using a numeric analogue scale, ranging from 0 (never/none/excellent) to 10 (each time of swallowing/very severe/very bad).

RESULTS

Endoscopic mucomyotomy was achieved in all 31 patients, with initial symptomatic improvement. Repeat treatment was required in 10 patients after a mean of 5.3 months, due to recurrence of symptoms. During a mean follow-up period of 26 months (range 14-49), 26 patients (84%) had long-term success of variable degree (65% with no or minimal remaining symptoms); four patients (13%) had insufficient relief and wanted a repeat treatment; and one patient (3%) underwent surgery. The success rate in the entire group was 84% (26/31) including those with repeat treatment, and 61% (19/31) if only success following a single treatment session was counted. Minor complications such as subcutaneous or mediastinal emphysema were observed in 23% and were conservatively managed. There were no major complications.

CONCLUSIONS

A single needle-knife mucomyotomy procedure can achieve long-term symptomatic improvement in about two out of three cases of Zenker's diverticulum. The success rate can be increased to above 80% by repeated sessions. Minor complications occur frequently but they can be conservatively managed. Major complications were not observed. Further long-term studies are warranted to elucidate the role of endoscopy as a definitive single treatment, with determination of prognostic parameters for a successful long-term outcome.

Spatial distribution of Salmonella, Escherichia coli O157:H7, and other bacterial populations in commercial and laboratory-scale sprouting mung bean beds

The reliability of testing spent irrigation water to assess the microbiological status of sprouting mung bean beds has been investigated. In commercial trials, the distribution of opportunistic contaminants within 32 bean sprout beds (25 kg of mung beans per bin) was assessed 48 h after germination. The prevalence of generic Escherichia coli, thermotolerant coliforms, and Aeromonas in sprouts (n = 288) was 5, 11, and 39%, respectively, and 57, 70, and 79% in the corresponding spent irrigation water samples (n = 96). Contamination was heterogeneously distributed within the seedbed. In laboratory trials, beans inoculated with a five-strain cocktail of either Salmonella or E. coli O157:H7 (10(3) to 10(4) CFU/g) were introduced (1 g/500 g of noninoculated seeds) at defined locations (top, middle, or base), and the beans were then sprouted for 48 h. When seeds inoculated with pathogens were introduced at the base or top of the seedbed, the pathogens were typically restricted to these sites and resulted in 44% of the spent irrigation water samples returning false-negative results. Introducing inoculated beans into the middle or at the presoak stage enhanced the distribution of both pathogens within the subsequent sprout bed and resulted in comparable levels recovered in spent irrigation water. The study demonstrated that even though screening a single sample of spent irrigation water is more reliable than testing sprouts directly, it does not provide an accurate assessment of the microbiological status of sprouting mung bean beds. Such limitations may be addressed by ensuring that bean batches are mixed prior to use and by taking spent irrigation water samples from multiple sites at the latter stages of the sprouting process.

C. elegans ced-13 can promote apoptosis and is induced in response to DNA damage

The p53 tumor suppressor promotes apoptosis in response to DNA damage. Here we describe the Caenorhabditis elegans gene ced-13, which encodes a conserved BH3-only protein. We show that ced-13 mRNA accumulates following DNA damage, and that this accumulation is dependent on an intact C. elegans cep-1/p53 gene. We demonstrate that CED-13 protein physically interacts with the antiapoptotic Bcl-2-related protein CED-9. Furthermore, overexpression of ced-13 in somatic cells leads to the death of cells that normally survive, and this death requires the core apoptotic pathway of C. elegans. Recent studies have implicated two BH3-only proteins, Noxa and PUMA, in p53-induced apoptosis in mammals. Our studies suggest that in addition to the BH3-only protein EGL-1, CED-13 might also promote apoptosis in the C. elegans germ line in response to p53 activation. We propose that an evolutionarily conserved pathway exists in which p53 promotes cell death by inducing expression of two BH3-only genes.

Chromophobe renal cell carcinoma: a comparative study of histological, immunohistochemical and ultrastructural features using high throughput tissue microarray

AIMS

In some cases distinction between chromophobe renal cell carcinoma (CRCC), oncocytoma and clear cell (conventional) renal cell carcinoma (eosinophilic variant) using routine light microscopy remains problematic. The present study investigates the level of agreement in the diagnosis of CRCC, as well as the histological features most frequently used for this diagnosis by two pathologists with a special interest in renal neoplasia. The sensitivity and specificity of immunohistochemical markers in cases with overlapping histological features in the diagnosis of CRCC were also studied. Electron microscopy was performed, as a diagnostic gold standard, on all of the cases.

METHODS AND RESULTS

Thirty-two renal tumours with predominantly eosinophilic cytoplasm were reviewed in a blinded fashion by two pathologists. The diagnosis and morphological features used to render each diagnosis were tabulated. Validation of the utility of keratin 7 and 20, epithelial membrane antigen (EMA), vimentin, CD10, parvalbumin, RCC antigen, antimitochondrial antibody and Hale's colloidal iron was performed by the construction of a tissue microarray (TMA) master block. Based on histological criteria alone, overall agreement on the diagnosis of these tumours was reached in 69% of the cases, while there was total disagreement in 12%. In 59% of the cases, total agreement was reached in classifying the case as a CRCC based on histology alone. Kappa statistics for interobserver variability were calculated as only slight agreement (kappa = 0.3). The histological features most frequently associated with a diagnosis of CRCC were accentuated cell borders (87%) and a combination of hyperchromatic wrinkled nuclei (79%) and perinuclear halos (74%). The most sensitive and specific marker for CRCC was parvalbumin (sensitivity 0.91; specificity 1.0). The immunohistochemical profile of EMA+/ vimentin- was useful but had low specificity (sensitivity 0.75; specificity 0.4). CD10 had the highest sensitivity (1.0) but worst specificity (0.25) for CRCC. Keratin 7 had high sensitivity (0.83) but fairly low specificity (0.37) for CRCC. Hale's colloidal iron and the RCC antigen marker were not contributory. Finally, the antimitochondrial antibody was found to be fairly sensitive (0.83) for excluding CRCC.

CONCLUSIONS

A small but significant proportion of renal tumours with cells having eosinophilic cytoplasm cannot be classified, even by experienced pathologists, based on histology alone. In these cases it is imperative to use markers with known sensitivity and specificity for the diagnosis of CRCC.

Attempted endoscopic en bloc resection of mucosal and submucosal tumors using insulated-tip knives: a pilot series

BACKGROUND AND STUDY AIMS

Endoscopic mucosal resection (EMR) of early gastrointestinal cancers has been shown to be effective in treating mucosal malignancies, but en bloc resection (where the entire tumor is removed in one piece) is often not achieved using conventional cap EMR. Other techniques, developed in Japan, include the application of different types of knife such as the insulated-tip instrument. We report our preliminary experience of the use of this knife, in conjunction with other techniques, in attempting en bloc resection of early mucosal cancers and adenomas and in the removal of submucosal tumors (SMTs) of the upper gastrointestinal tract.

PATIENTS AND METHODS

A total of 37 patients (26 men, 11 women, age range 53 - 86) were included in the study; 23 patients had 24 mucosal lesions amenable to EMR, and 14 patients had SMTs shown on endosonography to spare the muscularis propria. Lesions were located in the esophagus (n = 13), the stomach (n = 24), and the duodenum (n = 1); 40 % of the mucosal lesions were 20 mm or larger (mean size 18mm), whereas the mean size of the submucosal lesions was 23 mm. After submucosal saline injection, circumcision and dissection of the mucosal lesions was attempted with the aim of achieving en bloc resection. For SMTs, cap mucosectomy of the overlying mucosa was done first, and the tumors were then freed using saline injection, and finally resected using snare polypectomy.

RESULTS

The strict aim of the study, i. e. complete tumor removal in a single piece, was achieved in only 25 % of the mucosal lesions (some failures were due to unrecognized submucosal infiltration) and 36 % of the SMTs. When a more liberal definition of success was assumed, this rate increased to 65 % for mucosal lesions (piecemeal, no tumor found at surgery or follow-up endoscopy with biopsy) and 79 % for SMTs (piecemeal). No severe complications necessitating surgery or leading to major morbidity occurred. However, clinically significant complications were found in six patients (minor perforation managed conservatively (n = 1), severe pain without perforation (n = 1), bleeding requiring reintervention (n = 3), and aspiration (n = 1)).

CONCLUSIONS

Although we are convinced that methods of achieving en bloc resection of mucosal cancers and SMTs must be pursued, the insulated-tip knife in conjunction with conventional endoscopes still has limitations. Innovative endoscope design (double-channel scopes) as well as the development of new accessories will help to overcome the current limitations and further promote endoscopic tumor resection.

M. Behçet mit gastrointestinaler Beteiligung ohne Hinweis einer chronisch-entzündlichen Darmerkrankung

A case of a 32-year-old male patient with lower gastrointestinal bleeding is reported as an initial manifestation of Behçet's disease. The early diagnosis of this chronic-systemic disease is often very difficult, in particular with regard to the differentiation from chronic inflammatory bowel diseases. In addition, lower gastrointestinal bleeding is a rare manifestation of Behçet's disease. An immunosuppressive therapy was initiated and the course of the disease with recurrent oral ulcerations gave evidence for the diagnosis. Further bleeding episodes or other gastrointestinal symptoms have not been observed during a follow-up period of 36 months. The diagnostic problems and the therapeutic management of the disease are discussed in relation to neighbouring entities.

[Endoscopic therapy methods for gastroesophageal reflux]

Gastroesophageal reflux disease (GERD) is prevalent in 10% of the population. In addition to the established therapy, endoscopic antireflux procedures have been developed to improve the gastroesophageal reflux barrier. This can achieved by endoscopically placed sutures, application of radio frequency energy, or injection of biocompatible materials. These new techniques might be effective in some patients with GERD. To date, there are limited data on the effectiveness and safety of these methods. During a follow-up of 1-2 years, subjective parameters improved in 70-75% of the test patients such that no antisecretory treatment was required. Further, randomized, placebo-controlled studies are needed for objective evaluation of these promising new methods.

Incidence and electrophysiological characteristics of spontaneous ventricular tachyarrhythmias in high risk coronary patients and prophylactic implantation of a defibrillator

OBJECTIVES

To assess the incidence and electrophysiological characteristics of spontaneous ventricular tachyarrhythmias after implantable cardioverter-defibrillator (ICD) implantation for primary prevention.

DESIGN

Prospective observational study.

PATIENTS

41 consecutive patients, who fulfilled MADIT (multicenter automatic defibrillator implantation trial) I criteria, except for suppressibility by procainamide, and who received a prophylactic ICD.

INTERVENTIONS

Subpectoral implantation of an ICD.

MAIN OUTCOME MEASURES

Incidence of ventricular tachyarrhythmias and their electrophysiological characteristics with respect to timing of the arrhythmia, tachyarrhythmia cycle length, mode of termination, and clinical relevance.

RESULTS

During a mean (SD) follow up of 30 (21) months 18 of 41 (43.9%) patients experienced 142 appropriate ICD treatments. The mean (SD) time to first event was 9.6 (15.1) months. One patient had ventricular fibrillation (VF), 12 patients ventricular tachycardia (VT), and five both VT and VF. The mean (SD) cycle length of monomorphic VT was 306 (42) ms. Of 142 episodes, 117 (82.3%) were terminated by antitachycardia pacing and another 25 (17.6%) by ICD discharges. Cumulative survival of hypothetical death, defined as treated VT with a cycle length < 260 ms or VF, was 83.2% after one year and 78.4% after two years.

CONCLUSIONS

Patients with a left ventricular ejection fraction < 35%, a history of myocardial infarction, non-sustained VT, and inducible VT/VF are at high risk of VT/VF early after implantation. Therefore, implantation of a tiered treatment defibrillator seems to be justified.

A prospective, randomized multicenter trial comparing DoubleLayer and polyethylene stents for malignant distal common bile duct strictures

BACKGROUND AND STUDY AIMS

Endoscopic biliary stenting is an established treatment for malignant obstructive jaundice. Stent clogging continues to be a major problem with plastic stents. The aim of this study was to carry out a prospective comparison of two stents with different materials and shapes: the Olympus DoubleLayer stent (DLS; perfluoro alkoxy, without sideholes) and the standard polyethylene (PE) stent (with sideholes).

PATIENTS AND METHODS

A total of 120 patients (70 women; mean age 71, range 36 - 91) with jaundice due to malignant strictures of the middle to distal third of the common bile duct were randomly assigned to receive either DLS (n = 60) or PE (n = 60) biliary stents. Patients with cholangitis, hemobilia, previous biliary drainage, hilar stricture, or ampullary cancer were excluded.

RESULTS

In all, 28 DLS patients (47 %) and 17 PE stent patients (29 %) died without clinical evidence of stent occlusion after a mean of 114 and 105 days, respectively ( P < 0.05). Twenty-six DLS patients (43 %) and 38 PE stent patients (63 %) had symptoms of stent clogging after a mean of 144 and 99 days, respectively ( P < 0.05). Stent dysfunction (stent orifice impacted on the bile duct or duodenal wall, stent migration) was recorded in six DLS patients (10 %) and five PE patients (8 %) (n. s.). Kaplan-Meier analysis of DLS and PE stent clogging-free survival showed a significantly longer patency period with the DLS stents (P = 0.0005).

CONCLUSIONS

These results show that DoubleLayer stents have a longer patency period than PE stents. Patients who received PE stents had a higher risk of stent occlusion (relative risk 3.05; 95 % CI, 1.57 - 5.89) before death than DLS patients.

A randomized trial of unsedated transnasal small-caliber esophagogastroduodenoscopy (EGD) versus peroral small-caliber EGD versus conventional EGD

BACKGROUND AND STUDY AIMS

Unsedated esophagogastroduodenoscopy (EGD) has advantages over sedated EGD - e. g., prevention of side effects related to sedation, less patient monitoring, and less expense. This study compared the feasibility and tolerance of transnasal small-caliber (TSC-EGD) and peroral small-caliber EGD (PSC-EGD) with conventional EGD (C-EGD).

PATIENTS AND METHODS

A total of 150 patients referred for diagnostic EGD were randomly allocated to undergo either TSC-EGD, PSC-EGD, or C-EGD under local anesthesia if they agreed to receive sedation only on demand or in case of intolerance. Patients, endoscopists, and nurses completed questionnaires on the tolerability and quality of the examinations using a visual analogue scale (VAS), ranging from 1 (best/nonexistent) to 10 (worst/unbearable) after EGD. Small-caliber EGD and C-EGD were performed with 5.9-mm and 9.8-mm video endoscopes (Olympus), respectively.

RESULTS

The patients' age, sex, experience with EGD, and anxiety before EGD did not differ significantly between the three groups, each consisting of 50 patients. TSC-EGD failed in four of the 50 patients (8 %) because of a narrow nasal tract; they underwent PSC-EGD. Complete examinations, including the second part of the duodenum and biopsy sampling, were possible in all patients. Patients examined with an ultrathin instrument required sedation significantly less often (TSC-EGD 6 %, PSC-EGD 18 %, C-EGD 44 %; P < 0.01) and consequently spent less time in the recovery room. TSC-EGD was initially more painful on insertion, but caused less gagging (P<0.01) than peroral EGD during the whole procedure. TSC-EGD caused mild epistaxis in one case.

CONCLUSIONS

TSC-EGD was carried out safely and completely in 92 % of the patients. TSC-EGD and PSC-EGD were better tolerated and required sedation less often than conventional EGD. Transnasal diagnostic EGD appears to be a promising alternative to peroral EGD, as it is associated with less gagging and a high level of patient satisfaction.

Heat shock protein 60 expression in patients undergoing cardiac operations

AIM

Cardiomyocytes respond to stress with the expression of different heat shock proteins (HSP). The mitochondrial HSP60 is known to be expressed by various stress factors, including ischemia and reperfusion. The aim of this study was to investigate if HSP60 is increased in human myocardium after cardiac surgery.

METHODS

To determine if heat shock protein 60 accumulated in the myocardium of patients undergoing car-diac operations, right atrial samples before and after extracorporeal circulation were excised and immediately frozen in liquid nitrogen.

PATIENTS

we obtained 10 sequential right atrial specimens from 5 male patients in sinus rhythm undergoing elective cardiac surgery.

MEASURES

the HSP60 protein level was determined by SDS-PAGE, Western blot and quantified by optical densitometry according to the immunoreactive bands of actin.

RESULTS

The HSP60 concentration was unchanged in hearts after a single episode of hypothermic ischemia and reperfusion. Immunoblot analysis demonstrated HSP60 expression in all hearts. There was no correlation with the endurance of cardiopulmonary bypass or reperfusion time.

CONCLUSION

These findings indicate that myocardial HSP60 of patients undergoing cardiac operations is not increased after an obligatory period of ischemia, cardioplegic arrest and reperfusion. This might reflect an effective cardioprotection during ECC.

[Endoscopic ultrasound in routine clinical practice for staging adenocarcinomas of the stomach and distal esophagus]

PROBLEM

Endoscopic ultrasound (EUS) is an important diagnostic tool for determining the best therapeutic strategy (primary resection, neoadjuvant therapy or palliation only) to offer esophageal or gastric cancer patients.

PATIENTS AND METHODS

In the present study (1992-2001),we evaluated the accuracy of EUS in adenocarcinomas of the distal esophagus and stomach and compared our results with pathologists findings as the gold standard.

RESULTS

Of the 222 patients studied, the precise examination of 11% EUS was not completely possible due to severe tumor stenosis. The accuracy of EUS with respect to T, N+/- and TN+/- amounted to 51%, 65% and 34% in 131 patients with adenocarcinomas of the esophageal gastric junction and to 50%, 66% and 37% in 91 patients with adenocarcinomas located in the fundus, corpus or antrum of the stomach respectively. With respect to T-stage, the overstaging of tumors was more common than understaging, especially in pT2b-carcinomas. The subgroup analysis of the 131 EGJ adenocarcinoma patients showed that the results obtained by EUS were slightly better in type I (distal esophageal cancer) than in type II and III cardia carcinomas (proximal gastric cancer).When comparing two observation periods (1992-1996 and 1997-2001), the accuracy of endoscopic ultrasound staging was very similar in both periods for T-category (51% vs 49%) and N-category (63% vs 64%) as well as for combined TN-staging (36% vs 35%) respectively.

CONCLUSIONS

In clinical routine examinations of adenocarcinomas of the stomach and the distal esophagus, the accuracy of EUS is not as good as the excellent results in the past--mostly obtained under study conditions--may suggest.

[Electrophysiological characterization of connexin 40 deficient hearts--in vivo studies in mice]

Intercellular communication is not only mediated by extracellular transmitters, but also directly by gap junction channels. One channel is composed of two hexameric hemichannels which consist of six polypeptide subunits called connexines (Cx). In the mammalian heart the following connexines have been documented: Cx37, Cx40, Cx43, Cx45, Cx46, Cx50 and Cx57. The labeling by number represents the rounded, molecular mass of the amino acid sequences given in kD. If identical connexin-isotypes form both connexons of a gap junction channel, homotypic coupling exists and a homomeric gap junction channel is formed. Different connexin-isotypes within both connexons cause form heterotypic coupling and heteromeric gap junction channels. Each channel type has specific properties regarding permeability and electrical conductance. Beside a typical age-dependent alignment of gap junction channels on the surface of the cardiac myocytes, regional distribution of the different connexins is different at distinct parts of the mouse heart. Cx40 is not found in the ventricular working myocardium of mice. In the atria as well as in the conduction system, Cx40 is the most frequently expressed. In line with the localization and the conduction properties of distinct homotypic gap junction channels, the Cx40 deficient mouse is suitable for analysis of atrial arrhythmias. Cx40-deficiency in the mouse heart results in characteristic ECG changes like first degree atrioventricular block and prolongation of the QRS duration. Thus, an impairment of the sinuatrial, intraatrial and atrioventricular conduction properties is documented in Cx40 deficient mice. These observations are associated with an increased atrial vulnerability. The Cx40 deficient mouse provides a good example of the relevance of transgenic mouse models to clarify the mechanisms of arrhythmogenesis. The clinical impact of future transgenic mouse models depends on the cooperation of geneticists, basic researchers and clinicians.