An inexpensive point-of-care immunochromatographic test for Talaromyces marneffei infection based on the yeast phase specific monoclonal antibody 4D1 and Galanthus nivalis agglutinin

Talaromyces marneffei is a thermally dimorphic fungus that causes opportunistic systemic mycoses in patients with AIDS or other immunodeficiency syndromes. The purpose of this study was to develop an immunochromatographic strip test (ICT) based on a solid phase sandwich format immunoassay for the detection of T. marneffei antigens in clinical urine specimens. The T. marneffei yeast phase specific monoclonal antibody 4D1 (MAb4D1) conjugated with colloidal gold nanoparticle was used as a specific signal reporter. Galanthus nivalis Agglutinin (GNA) was adsorbed onto nitrocellulose membrane to serve as the test line. Similarly, a control line was created above the test line by immobilization of rabbit anti-mouse IgG. The immobilized GNA served as capturing molecule and as non-immune mediated anti-terminal mannose of T. marneffei antigenic mannoprotein. The MAb4D1–GNA based ICT showed specific binding activity with yeast phase antigen of T. marneffei, and it did not react with other common pathogenic fungal antigens. The limit of detection of this ICT for T. marneffei antigen spiked in normal urine was approximately 0.6 μg/ml. The diagnostic performance of the ICT was validated using 341 urine samples from patents with culture- confirmed T. marneffei infection and from a control group of healthy individuals and patients with other infections in an endemic area. The ICT exhibited 89.47% sensitivity, 100% specificity, and 97.65% accuracy. Our results demonstrate that the urine-based GNA–MAb4D1 based ICT produces a visual result within 30 minutes and that the test is highly specific for the diagnosis of T. marneffei infection. The findings validate the deployment of the ICT for clinical use.     

Giant prolactinoma presented as unilateral exophthalmos in a prepubertal boy: response to cabergoline

We report the case of a giant prolactinoma in a 7-year-old boy, which was complicated by unilateral exophthalmos. The initial levels of prolactin (PRL) were about 80,000 microU/ml. Treatment with cabergoline (CAB) resulted in rapid normalization of serum PRL (6 weeks after initiation of treatment) and reduction of tumor size. In particular, magnetic resonance imaging (MRI), which was done 2.5 months after the patient was put on CAB, revealed tremendous improvement with a decrease in the size of the tumor which now showed no extrasellar extension. Subsequent MRI studies demonstrated further improvement. Exophthalmos, anisocoria and visual fields improved. In summary, this patient represents the first report of the therapeutic use of CAB as the primary mode of treatment in a 7-year-old boy with infiltrative giant prolactinoma complicated by unilateral exophthalmos. It is a noninvasive treatment that can preserve and restore vision, as well as pituitary function, and is preferable to surgery or radiation in the treatment of prolactin-secreting macroadenoma in childhood and adolescence.     

Intraspecific differentiation of social behavior and shelter selection in Mesobuthus gibbosus (Brullé, 1832) (Scorpiones: Buthidae)

We compared seasonal shelter selection and social behavior of Mesobuthus gibbosus from autumn to mid-summer in two similar phryganic ecosystems, in continental Greece (near Volos city) and in insular Greece (eastern Crete), and in the laboratory under simulated abiotic conditions. Our results showed that shelter selection is a critical indicator of the seasonal social behavior of the species. The abrupt climatic changes in spring caused a differentiation in shelter selection between the cold period (November–February) and the warm period (March–June) at both sites. Sociality was exhibited only during winter in the field and was more extensive under cold conditions in the laboratory. Co-occurrence of scorpions proved to be age-specific, facilitated by population density and by harsh abiotic conditions during winter, and negatively influenced by intraspecific competition, which was higher in continental Greece. The response of scorpions to changes of abiotic factors reveals synchronization of seasonal shelter selection with climatic changes.