A highly sensitive and specific chemiluminescent enzyme-linked immunosorbent assay for diagnosis of active Trypanosoma cruzi infection

BACKGROUND: Chagas' disease is transmitted to man either by the bite of insects harboring Trypanosoma cruzi or by the transfusion of blood from infected donors. The conventional serologic testing as presently used in blood banks in South America is unsatisfactory, because of a high number of inconclusive and false-positive results. Other methods such as polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA) with recombinant antigens have been proposed, but inherent difficulties have so far precluded their adoption in the large-scale screening required by blood banks. STUDY DESIGN AND METHODS: A highly sensitive and specific chemiluminescent ELISA using a purified trypomastigote glycoconjugate antigen and a complex epimastigote antigen was devised for the diagnosis of active T. cruzi infection. RESULTS: Chemiluminescent ELISA was 100-percent sensitive in the diagnosis of 100 cases of confirmed Chagas' disease. Inconclusive results and false-positive reactions were eliminated in a panel of 115 sera.The specificity of the chemiluminescent ELISA was 100 percent with a purified trypomastigote glycoconjugate antigen and 99.7 percent with a complex epimastigote antigen when applied to 1000 normal human sera and 288 heterologous sera from patients with other infections, including leishmaniasis, and vaccinated individuals. CONCLUSION: The chemiluminescent ELISAs provide a test that is highly sensitive (purified trypomastigote glycoconjugate and complex epimastigote antigens) and specific (purified trypomastigote glycoconjugate antigen) for Chagas' disease diagnosis. It can be used in blood bank screening and to monitor the treatment of patients undergoing chemotherapy.     

Naratriptan: biological profile in animal models relevant to migraine

The biological profile of naratriptan (N-methyl-3-(1-methyl-4-piperidinyl)-1H-indole-5-ethane-sulphona-mide), a novel 5HT_1B/1D receptor agonist, was investigated in a variety of experimental models of relevance to migraine. Naratriptan has high affinity for human recombinant 5HT_1B and 5HT_1D receptors (pKi = 8.70.03 and 8.30.1, respectively) and causes contractions of dog isolated basilar and middle cerebral artery (EC₅₀ values of 0.11 and 0.07 M, respectively). Naratriptan causes small contractions of human isolated coronary arteries (EC₅₀ value of 0.17 M; maximum contraction equivalent to 33% of 5HT maximum). In anaesthetized dogs, naratriptan causes selective vasoconstriction of the carotid arterial bed (CD₅₀ dose = 193 g kg⁻¹) and, in anaesthetized rats, naratriptan selectively inhibits neurogenic plasma protein extravasation in the dura (ID₅₀ = 4.1 g kg⁻¹). In a variety of antinociceptive tests, naratriptan has no effect even at high doses. In conscious rats and dogs, naratriptan has high oral bioavailability (71% and 95%, respectively). The data show that naratriptan is a selective agonist at 5HT_1B/1D receptors, with a pharmacological profile very similar to that of sumatriptan, albeit 2-3 fold more potent. These observations, coupled with high oral bioavailability in animals, suggest that naratriptan has the profile of an orally effective anti-migraine drug.     

Cytokine-targeting biologics for allergic diseases

Objective

Asthma and allergic diseases continue to increase in prevalence, creating a financial burden on the health care system and affecting the quality of life for those who have these diseases. Many intrinsic and extrinsic factors are involved in the initiation and maintenance of the allergic response. Cytokines are proteins with growth, differentiation, and activation functions that regulate and direct the nature of immune responses.

Comparative effects of insulin on adipose tissue segments and isolated fat cells of rat and man

In vitro metabolism of glucose-1-¹⁴C by adipose tissue into ¹⁴CO₂ and total ¹⁴C lipids in rat and man was compared employing both adipose tissue segments and isolated fat cells prepared from the same donor. In the rat, the basal glucose metabolism and response to insulin decreased with increasing body weight for both adipose tissue segments and isolated cells. Regardless of age, the isolated cells exhibited a persistently higher metabolic activity. Of the parameters selected, conversion to CO₂ was more pronounced than that to lipid.     

Aplastic crisis as a complication of congenital dyserythropoietic anemia type II

A transient aplastic crisis (TAC) is a well-known complication in all types of chronic hemolytic anemia but only 2 cases of such an event were described in congenital dyserythropoietic anemias (CDAs). Here, we report a third case, and by retrospective chart review of 78 cases we found evidence of TAC in 8 further patients with CDA II, with serological evidence of previous human parvovirus B19 (B19V) infection in all but one. Although B19V infection results in TAC in only a minority of patients with CDA, physicians responsible for these patients should be aware of such a potentially life-threatening complication. Testing for B19V-specific IgG is recommended in patients with CDA to estimate the risk of a possible future aplastic crisis.     

Development of the Manchester framework for the evaluation of emergency department pharmacy services

International Journal of Clinical Pharmacy - Many countries, including the United Kingdom, have established Emergency Department (ED) pharmacy services where some ED pharmacists now work as...