Interaction of laxatives with enzymes of cyclic AM P metabolism from human colonic mucosa

The mechanism by which laxatives such as dioctyl sodium sulfosuccinate and ricinoleic acid evoke colonic fluid secretion has been suggested to involve mucosal cyclic AMP. Ricinoleic acid and dioctyl sodium sulfosuccinate were tested for their capacity to modulate the key enzymes of cAMP-metabolism--adenylate cyclase and cAMP-phosphodiesterase--in human colonic mucosa. Both laxatives were ineffective stimuli of human colonic adenylate cyclase. In contrast to ricinoleic acid, dioctyl sodium sulfosuccinate was a competitive inhibitor of soluble cAMP-phosphodiesterase activity. These experiments suggest that the cathartic properties of dioctyl sodium sulfosuccinate in human colonic mucosa might be mediated by cyclic AMP via inhibition of soluble phosphodiesterase activity.     

Robotic Catheter Navigation within the Left Ventricle

Robotic navigation systems aim to improve ablation catheter maneuverability, tissue contact, and stability. These attributes suggest that such systems could enhance outcomes in the ablation of ventricular tachycardia (VT). To date, however, ablation has been confined to the atria. We present a case in which robotic catheter navigation alongside three‐dimensional anatomical mapping enabled successful ablation of VT within the left ventricle. (PACE 2011; 34:e102–e104)     

Safety of Transcatheter Aortic Valve Implantation in a Hospital With Visiting On‐Site Cardiac Surgery

Objectives

To describe the feasibility and safety of transcatheter aortic valve implantation (TAVI) with a visiting on‐site cardiac surgery program for surgical back‐up.

Background

Both European and American guidelines recommend institutional cardiac surgery back‐up for TAVI. However, the conversion to cardiac surgery is very rare, many complications of TAVI can be managed by catheter techniques and a visiting team can also provide surgical stand‐by. Therefore, the need for institutional cardiac surgery (by a surgeon who routinely performs conventional surgical valve replacement at the institution performing TAVI) has been questioned.

Methods

A retrospective review of consecutive TAVI cases with visiting on‐site cardiac surgery was performed. Key demographic, echocardiographic, and procedural data were collected prospectively.

Results

A total of 97 patients (81.9 ± 6.3 years) with high‐risk criteria (log Euroscore 21.6 ± 14.4, chronic renal failure 39.2%, severe systolic dysfunction 24.7%) underwent TAVI with visiting on‐site cardiac surgery at our institution. Local anesthesia with or without conscious sedation was used in 94.8% of patients. Procedural technical success was 100%, with 2 episodes of tamponade (both treated with pericardiocentesis) and a 16.5% vascular complication rate (all treated conservatively or percutaneously). Thirty‐day mortality was 3.1%, with 5.2% rate of stroke and 8.2% rate of major bleeding. There were no conversions to surgery.

Conclusions

TAVI can be done safely in the setting of a hospital with visiting on‐site cardiac surgery. This requires careful patient selection, experienced operators and surgeons in experienced centers with well‐established criteria and processes of care. In this setting, it may be an option for hospitals without institutional cardiac surgery. (J Interven Cardiol 2015;28:76–81)

     

Whooping-cough vaccination: historical,social and political controversies

• ? New acellular whooping cough vaccines may have the effect of leading us to forget that infectious diseases such as whooping cough have declined in the context of particular historical, social conditions and persist in the context of particular types of social inequalities.
• ? The debates over the existence of damage from whole-cell whooping cough vaccine, and the respective risks of the vaccine and the disease arc still unresolved owing to methodological limitations of studies on both sides of the argument.
• ? One-sided health ‘education’ campaigns on whooping cough vaccine have questionable ethics, and suppression of dissenting views is counterproductive.
• ? Health professionals and parents have a right to know the political context of the debate.

     

Treatment of Cholesterol Gallstones with Chenic acid

Twenty-five patients were treated with chenie acid over the past three years. Asymptomatic or with mild nonspecific symptoms of "gallbladder dyspepsia" patients with radiolucent gallstones in functioning gallbladders were selected for this therapeutical trial. Clinical evaluation, liver tests and cholecystograms were performed periodically. In the functioning gallbladders the stone size (diameter of the largest stones) was measured during each standard cholecystography and classified as: smaller, less than 10 mm. and larger, more than 10 mm. Eight patients (with small gallstones) were treated less than six months and only one has had a partial dissolution. Of the 17 patients treated more than six months, the gallstones (small size) completely disappeared in nine (52.9%), most of them before 18 months of treatment and became partially smaller in three (17.6%) before 24 months of therapy. No change at all was observed in five patients between 18 and 24 months of treatment. In two of the nine patients in whom the cholecystograms demonstrated complete dissolution of gallstones, reappearance of small radiolucent gallstones was observed again six months after the drug was discontinued but reinstatement of chenic acid therapy again produced, after three months, complete dissolution of the gallstones. In our experience, therapy with chenie acid, with a daily dose of 750 mg. does not cause significant side-effects and offers a rational, effective, safe alternative to surgical treatment in a selected group of patients depending upon a reasonable clinical judgment.     

SUPERFICIAL BLADDER TUMORS AND INCREASED REACTIVITY AGAINST MYCOBACTERIAL ANTIGENS BEFORE BACILLUS CALMETTE-GUERIN THERAPY

Purpose

The precise mechanism of action of bacillus Calmette-Guerin (BCG) in bladder cancer treatment remains poorly understood. Whether bladder tumor cells are destroyed by nonspecific mechanisms or targeted by specifically activated lymphocytes recognizing cognate antigens is unclear. To investigate a possible cross-reactivity between BCG and bladder cell tumors, we tested before BCG treatment the lymphoproliferation of peripheral blood lymphocytes against several mycobacterial antigens, including the secreted fibronectin binding antigen 85 complex from BCG (AG 85) in patients with superficial bladder tumors compared to control matched patients.

Materials and Methods

Using a whole blood assay, T cell response against purified protein derivative, BCG extract, whole BCG, purified AG 85, and the nonspecific mitogens pokeweed and phytohemagglutinin was investigated in 79 patients with superficial bladder tumors before BCG and in 39 control subjects without malignancy matched for age and sex. Neither group had a history of tuberculosis. Lymphoproliferation was measured with a tritiated thymidine uptake assay on day 7 of culture.

Results

Of the 79 patients with superficial transitional cell carcinoma, a significant lymphoproliferative response before BCG against PPD, BCG extract, whole BCG and AG 85 was observed in 65 (82.2%), 67 (84.81%), 30 (37.97%) and 49 (62.02%) patients, respectively. Of the 39 controls only 26 (64.1%), 23 (58.9%), 3 (7.7%) and 3 (7.7%) patients, respectively, had a significant lymphoproliferation against PPD, BCG extract, BCG and AG 85 (p >0.05, p = 0.004, p = 0.00001 and p = 0.00001, respectively). In terms of lymphoproliferative levels, patients with superficial transitional cell carcinoma also showed a significantly higher response against PPD (p = 0.000012), BCG extract (p = 0.000001), AG 85 (p = 0.000001), whole BCG (p = 0.00001) and pokeweed (p = 0.01) than controls but not against phytohemagglutinin.

Conclusions

Patients with superficial transitional cell carcinoma demonstrate an increased lymphoproliferation against mycobacterial antigens before BCG compared to control subjects. Although a nonspecific activation of the immune system cannot be excluded at this stage, our data may suggest the possible existence of bladder cancer antigens cross-reactive with mycobacterial antigens responsible for boosting precursor cells witnessing previous contacts with mycobacteria. The implication of these findings in the antitumoral mechanism of action of BCG are under investigation.