Comparison of prognosis and safety of pacemaker implantation in patients aged less than or 85 years and older

Journal of Interventional Cardiac Electrophysiology - Cardiac conduction disturbance necessitating pacemaker implantation is common among elderly patients. However, patients often have...     

Angiotensin II-Forming Systems in Cardiovascular Diseases

Both the systemic and the tissue renin–angiotensin system (RAS)-are heavily involved in cardiovascular homeostasis, but their excess activation seems to be associated with increased morbidity and mortality in various stages of cardiovascular diseases, since angiotensin-converting enzyme (ACE) inhibitors have been shown to improve hypertension, congestive heart failure, and acute myocardial infarction. A clinical megastudy (ELITE) of elderly patients has recently shown that an AT1 receptor antagonist was superior to an ACE inhibitor for improvement of patients' prognosis. One of the possible mechanisms of this beneficial effect of the AT1 receptor antagonist compared to the ACE inhibitor could be the blockade of all the angiotensin (Ang) II formed not only by ACE but also by alternative pathways.Recent studies have disclosed that chymase, the most abundant Ang II-forming enzyme in human tissues, could be involved in the development of atherosclerosis, the remodeling of the myocardium after infarction or hypertrophy, restenosis after vascular injury, and chronic inflammatory conditions. Kallikrein-dependent Ang II formation also seems to take place under various ischemic conditions, as shown in the ischemic dog heart after ligation of a coronary artery, human leg circulation of patients with arteriosclerosis obliterans, or systemic circulation during a graded exercise. However, detailed mechanisms of non-ACE Ang II-forming enzymes involved in these pathological changes are not known. Current knowledge about ACE and non-ACE Ang II-forming enzymes in cardiovascular diseases are reviewed in this article.     

Carrier Status of Leptospirosis Among Cattle in Sri Lanka: A Zoonotic Threat to Public Health

Leptospirosis is a zoonotic disease of global importance and one of the notifiable diseases in Sri Lanka. Recent studies on human leptospirosis have suggested that the cattle could be one of the important reservoirs for human infection in the country. However, there is a dearth of local information on bovine leptospirosis, including its implications for human transmission. Thus, this study attempted to determine the carrier status of pathogenic Leptospira spp in cattle in Sri Lanka. A total of 164 cattle kidney samples were collected from the meat inspection hall in Colombo city during routine inspection procedures conducted by the municipal veterinary surgeons. The DNA was extracted and subjected to nested PCR for the detection of leptospiral flaB gene. Amplicons were sequenced, and phylogenic distances were calculated. Of 164 samples, 20 (12.2%) were positive for flaB‐PCR. Sequenced amplicons revealed that Leptospira species were deduced to L. borgpetersenii (10/20, 50%), L. kirschneri (7/20, 35%) and L. interrogans (3/20, 15%). The results indicate that a high proportion of the sampled cattle harbour a variety of pathogenic Leptospira spp, which can serve as important reservoirs for human disease.     

Exacerbation of Established Collagen-Induced Arthritis in Mice Treated with An Anti—T Cell Receptor Antibody

Objective. To investigate the effect of T cell depletion on established collagen-induced arthritis (CIA) in mice, using monoclonal antibodies (MAb) to T cell receptor α/β (TCRα/β). In addition, experiments using anti-CD3 MAb were performed for comparison. Methods. CIA was induced in male DBA/1 mice by immunizing them twice with bovine type II collagen (CII). The arthritis score and anti-CII antibody titers were examined serially. Proportions of T cells were determined by fluorescence-activated cell sorter (FACS) analysis on spleen cells or peripheral blood cells. Results. When anti-TCRα/β MAb was injected on the day of CII priming, no arthritis was detected in association with depressed anti-CII antibody titers. Unexpectedly, however, when MAb was given after arthritis was established, a rapid exacerbation of arthritis was observed, which resulted in ankylosis of most joints. Anti-CII antibody titers were not affected. The addition of anti-TCRγ/δ MAb had no effect on the augmented arthritis. T cell depletion by anti-CD3 MAb during established CIA also caused an enhancement of arthritis, which was, however, weak and only transient. FACS analysis revealed that the early improvement of arthritis after the transient augmentation seen in the mice treated with anti-CD3 MAb paralleled the early recovery of α/β T cells in the periphery. Conclusion. The present results support the concept that α/β T cells, in general, may play a regulatory role in the clinical course of murine CIA after disease onset. Therefore, caution is recommended when using intensive T cell—targeted therapy in patients with rheumatoid arthritis.     

Choline acetyltransferase and acetylcholinesterase activities in muscles of aged mice

The activities of choline acetyltransferase (CAT) and acetylcholinesterase (AChE) were assayed in intact diaphragm, extensor digitorum longus (EDL), and soleus muscles or their homogenates of young (2-6 months) and aged (24-34 months) mice. CAT activity (per mg of protein) was significantly higher in diaphragm and soleus of old mice in comparison with the young but the age change in EDL was negligible. On the other hand, AChE activity (per mg of protein) was significantly higher in EDL of old mice but in diaphragm and soleus muscles the enzyme activity did not show any significant change statistically. The diaphragm muscle was divided into two fractions, one being neuromuscular (NM) fraction and the other the remainder of the muscle (M fraction). No appreciable change in the ratio of the enzyme activities of NM fraction to the one of M fraction was obtained between the young and aged preparations. Thus, it seems likely that there is an age-related change in CAT and AChE activities which might be affected by the degree to which muscle activity is maintained.     

Secondary solid tumors after allogeneic hematopoietic SCT in Japan

To evaluate the incidence and risk factors for secondary solid tumors in Japan after allogeneic hematopoietic SCT (allo-HSCT), 2062 patients who had received allo-HSCT between 1984 and 2005 were retrospectively analyzed. Twenty-eight patients who developed 30 solid tumors were identified a median of 5.6 years after transplantation. The risk for developing tumors was 2.16-fold higher than that of the age- and sex-adjusted general population. The cumulative incidence of solid tumors at 10 years after allo-HSCT was 2.4%. The risk was significantly higher for tumors of the skin, oral cavity and esophagus (standard incidental ratio 40.23, 35.25 and 10.73, respectively). No increase in gastric, colon or lung cancer, despite being the most prevalent neoplasm in the Japanese, was observed. In multivariate analysis, occurrence of chronic GVHD and malignant lymphoma as a primary disease was associated with a higher risk for developing solid tumors. Eighteen patients are still alive, and their 5-year probability of survival since diagnosis of solid tumors is 59.7%. Our data suggest that the incidence and risk factors of secondary solid tumors in Japanese allo-HSCT recipients are comparable to those reported in Western countries and emphasize that the early detection of solid tumors has a crucial role in improving OS.