Total and specific IgE (house dust mite and intestinal helminths) in asthmatics and controls from Gondar, Ethiopia

BACKGROUND: The role, if any, of parasitosis in the development of asthma remains incompletely understood; both 'protective' and 'predictive' associations have been reported. We report a study which examined immunoglobulin (Ig) E responses to two common helminths in asthmatics living in Ethiopia. OBJECTIVE: To compare the frequencies of specific IgE antibodies to Ascaris and Necator species and to Der p 1 among 84 adult asthmatics and a referent group of nonasthmatics. METHODS: A case-control analysis. RESULTS: Total IgE levels were not different between the two groups. The presence of specific IgE to Der p 1 was strongly associated with asthma (P = 0.001). Raised levels of Ascaris-(P = 0.010) and Necator- (P = 0.001) specific IgE antibodies were more common among referents; there were no associations between specific IgE production to Der p 1 and either of the two parasites. CONCLUSION: These findings confirm the association between Der p 1 sensitization and asthma among urban, adult Ethiopians. While they also indicate a negative relationship with two indicators of helminth infestation it appears that this is not mediated through the immunological response to common aeroallergens.     

Vasopressin-induced hyponatremia in an adult normotensive trauma patient: A case report

BACKGROUND Arginine vasopressin is a neuropeptide produced in the hypothalamus and released by the posterior pituitary gland. In addition to maintaining plasma osmolarity, under hypovolemic or hypotensive conditions, it helps maintain plasma volume through renal water reabsorption and increases systemic vascular tone. Its synthetic analogues are widely used in the intensive care unit as a continuous infusion, in addition to hospital floors as an intravenous or intranasal dose. A limited number o...     

Leukotriene receptor antagonists. 1. Synthesis and structure-activity relationships of alkoxyacetophenone derivatives

A series of derivatives of 2,4-dihydroxy-3-propylacetophenone(1) were prepared and examined for their ability to block leukotriene D4 (LTD4) induced contraction of guinea pig ileum. Straight-chain carboxylic acids where the carboxyl group was separated from the acetophenone moiety by varying numbers of methylenes were evaluated, and maximum activity was obtained with the pentamethylene acid (6). Examination of ring substitution showed that the 2-propyl-3-hydroxy-4-acetyl substitution pattern was required for maximum LTD4 antagonist activity. Additional chain terminal groups were examined, and the acidic 5-tetrazolyl group separated from the acetophenone moiety by four to seven methylenes (26, 23, 27, 28) gave excellent in vitro and in vivo activities. Compound 26 (LY171883) had the best balance of in vitro and in vivo activity. It lacked bronchospastic activity at the doses administered and has been chosen for clinical evaluation.     

Inflammation, heat shock proteins and periodontal pathogens in atherosclerosis: an immunohistologic study

Background:  Inflammation is a significant component of atherosclerosis lesions. Bacteria, including periodontopathogens, have been demonstrated in atherosclerotic plaques and cross-reactivity of the immune response to bacterial GroEL with human heat shock protein 60 has been suggested as a link between infections and atherosclerosis.
Methods:  In this study, the nature of the inflammatory infiltrate and the presence of human heat shock protein 60 and GroEL were examined in 31 carotid endarterectomy specimens. Additionally, monoclonal antibodies were used to detect the presence of six bacteria, including those implicated in periodontal disease.
Results:  The inflammatory cell infiltrate of the lesions was dominated by CD14⁺ macrophages and CD4⁺ T cells. Most cells of the infiltrate as well as the endothelium were HLA-DR⁺, indicating activation; however, there was an absence of CD25 expression, demonstrating that the activated T cells were not proliferating. Few CD1a⁺ and CD83⁺ cells were noted. Human heat shock protein 60 expression was evident on endothelial cells and cells with the appearance of smooth muscle cells and lymphocytes. GroEL and bacteria were detected within intimal cells. Chlamydia pneumoniae, Porphyromonas gingivalis, Fusobacterium nucleatum, Tannerella forsythia, Prevotella intermedia , and Actinobacillus actinomycetemcomitans were found in 21%, 52%, 34%, 34%, 41%, and 17% of arteries, respectively.
Conclusion:  These results give evidence for a specific immune response associated with atherosclerosis. Whether bacteria initiate the observed inflammation in atherosclerotic lesions is not clear; however, the present study shows that maintenance of inflammation may be enhanced by the presence of periodontopathic bacteria.     

Differential block of cardiac delayed rectifier current by class Ic antiarrhythmic drugs: evidence for open channel block and unblock.

OBJECTIVE: The aim was to compare the effects of the class Ic antiarrhythmic drugs flecainide, encainide, and recainam on the delayed rectifier current, IK. METHODS: Membrane currents were studied using the single suction pipette voltage clamp technique in freshly dissociated cat ventricular myocytes bathed in HEPES buffered physiological saline at 32 degrees C. RESULTS: Flecainide and encainide decreased IK with IC50 values of 2.1 microM and 6 microM, respectively. Recainam (100 microM) reduced IK by only 7 (SEM 3)% after 20-30 min exposure and by 19% after an 80 min exposure (IC50 > 400 microM). None of the compounds blocked the inward rectifier, IK1. Block of IK by flecainide and encainide increased with depolarisation following a voltage dependence similar to that describing channel activation. Flecainide and encainide also slowed the time course of the IK tail currents, consistent with drug dissociating from open channels. CONCLUSIONS: The observed voltage dependence for IK block by flecainide and encainide resembles the interaction reported between these agents and the excitatory sodium channel, ie, depolarisation enhances block while repolarisation leads to removal of block. The results further suggest that the electrophysiological profile of class Ic agents can have a markedly different ionic basis, ie, K+ channel block by flecainide and encainide is balanced by a potent block of sodium channels, while recainam appears to be a weak but relatively specific blocker of sodium channels only. These differences are not readily accommodated by the current Harrison-Vaughan-Williams classification scheme, and suggest the possibility that potentially important drug specific differences can exist within the same antiarrhythmic drug class.     

Outcome of occupational asthma after cessation of exposure: a systematic review

BACKGROUND: Patients with occupational asthma, and their medical advisers, need valid information about the prognosis of their disease. METHODS: A systematic review of the published literature on the symptomatic and functional outcomes of occupational asthma was carried out after avoidance of exposure to the causative agent. Through a full search of electronic and bibliographic sources, original studies documenting complete recovery from asthma (n = 39,1681 patients) or improvement in non-specific bronchial hyper-responsiveness (NSBHR; n = 28,695 patients) were identified. The median duration of follow-up was 31 (range 6-240) months for studies of symptomatic recovery and 37 (6-240) months for studies of NSBHR. Most studies were of patients recruited from special clinics. RESULTS: Reported rates of symptomatic recovery varied from 0% to 100%, with a pooled estimate of 32% (95% CI 26% to 38%). These rates were lower with increasing age (p = 0.019) and among clinic based populations (p = 0.053). Patients with the shortest durations of exposure (< or =76 months) had the highest rate of recovery (36%; 95% CI 25% to 50%), but the effect was not linear. The pooled prevalence of persistent NSBHR at follow-up was 73% (95% CI 66% to 79%). This figure was higher among patients whose disease was due to high-molecular-weight agents (p = 0.006) and, less clearly, those from clinic-based populations (p = 0.561). In between-study comparisons, no clear patterns of improvement relating to total duration of exposure or follow-up were found. From within-study comparisons there was some evidence that a shorter duration of symptoms was associated with a higher rate of symptomatic recovery. CONCLUSION: The available data on the prognosis of occupational asthma are insufficiently consistent to allow confident advice to be given to patients with the disease. Clinicians and epidemiologists with an interest in this disease should consider a collaborative and carefully standardised study of the prognosis of occupational asthma.     

Bolus thrombolytic infusion during prolonged refractory cardiac arrest of undiagnosed cause

Acute myocardial infarction (AMI) and pulmonary embolism (PE) account for about 70% of cardiac arrest. Although thrombolytic therapy is an effective therapy for both AMI and PE, it is not routinely recommended during cardiopulmonary resuscitation (CPR) for fear of life threatening bleeding complications. Numerous case reports and retrospective studies have suggested a beneficial effect of thrombolytics in cardiac arrest secondary to AMI and PE; however, we present a case of successful use of bolus thrombolytics during CPR in a patient with undifferentiated cardiac arrest (undiagnosed cause) after prolonged conventional resuscitation without success.     

Unprompted Mechanical Switch Use in Individuals with Severe Multiple Disabilities: An Evaluation of the Effects of Body Position

Eight women with severe multiple disabilities were provided with simple mechanical switches that when depressed, activated battery-operated leisure items. Switches were provided for 1 hr during recreation when participants were sitting in wheelchairs and for 2 hr during therapeutic positioning when participants were lying on their beds or on wedges. No instructions or physical prompts were used to teach or maintain depression of the switch. Duration of switch depression in each session was recorded in 2 experimental conditions: (a) sessions when switch depression produced immediate activation of the leisure device and (b) sessions when switch depression produced no activation. Seven of eight participants showed higher rates of switch depression during conditions of immediate activation of the leisure device than in no-activation conditions. Seven of eight participants also showed similar rates of switch depression across conditions in both sitting and nonsitting positions.