Peptides specific for Mycobacterium avium subspecies paratuberculosis infection: diagnostic potential.

Mycobacterium avium subspecies paratuberculosis (Map) is the causative agent of Johne's disease (JD). Current serological diagnostic tests for JD are limited by their sensitivity when used in sub-clinical stages of the disease. Our objective was to identify peptides that mimic diagnostically important Map epitopes that might be incorporated into a new-generation JD diagnostic. Four peptides were isolated from a phage-displayed random peptide library by screening on antibodies derived from Map-infected goats. The peptides were recognised by antibodies from Map-infected goats but not by antibodies from uninfected goats. The peptides elicited immune responses in rabbits, which reacted strongly with bona fide Map antigens proving the peptides were true epitope mimics. To assess the diagnostic value a panel of goat sera was screened for reactivity's with peptides. The peptides were recognised by antibodies from a proportion of goats infected with Map compared with control animals with a diagnostic specificity of 100% and the sensitivity ranged from 50 to 75%. Combinations of any two peptides improved sensitivity 62.5-87.5% and 100% sensitivity was achieved with three of the four peptides in combination. These data suggest peptides representing diagnostically important Map epitopes could be incorporated into a sensitive diagnostic test.

Beta-blocker effects on postoperative atrial fibrillation.

OBJECTIVES: To determine whether restarting of Beta Blocker following cardiac surgery would reduce the incidence and the severity of post-operative atrial fibrillation (AF). METHODS: 210 patients who underwent elective coronary artery bypass grafting were randomized to control (C) (n = 105) and Beta Blockers (BB) (n = 105) groups. Preoperatively all patients were on one type or another of betablockers. Postoperatively only the (BB) group received the medication. Both groups were well matched and had the same cardioplegic technique. RESULTS: It was found that; (1) post op (AF) developed in 40 patients of group (C) and in 18 patients of group (BB) P value < 0.02. (2) 73% of (AF) patients in group (C) and 81% in group (BB) were older than 70 years of age. (3) 76% of the (AF) in (BB) group versus 43% in (C) group were converted to sinus rhythm or to a stable controlled rhythm within 24 h or less. P value < 0.01. CONCLUSIONS: The results indicate that restarting the Beta Blockers in the post-operative period after coronary bypass grafts significantly control the incidence and the severity of atrial fibrillation. Also it confirms the strong relation between the older age and (AF) occurrence.

Opening the pleura during internal mammary artery harvesting: advantages and disadvantages.

OBJECTIVE: To evaluate the findings of previous studies that opening of the pleura during internal mammary artery (IMA) dissection might be an important factor in increasing the operative morbidity. DESIGN: A randomized control trial. SETTING: A university hospital. PATIENTS: Two hundred and eighty consecutive patients with no significant pulmonary disease. INTERVENTION: Harvesting of the IMA with (130 patients) or without (150 patients) opening the pleura. MAIN OUTCOME MEASURES: Comparison of the incidence of pleural effusion, cardiac tamponade, postoperative respiratory complications and the hospital stay. RESULTS: Pleural effusion occurred more often in the patients who had opening of the pleura (20% versus 5%); however, none of the patients required tapping. Postoperative bleeding with cardiac tamponade occurred in five patients in the closed pleura group. Six patients in the open pleura group had postoperative bleeding but without tamponade. The average postoperative stay was 7 days for both groups. No significant differences were recorded in postoperative respiratory complications. CONCLUSIONS: Opening of the pleura during IMA harvesting does not increase the operative morbidity. It may have other advantages and is recommended in most cases of IMA harvesting.