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The biology of Episimus utilis Zimmerman, a natural enemy of Brazilian peppertree, Schinus terebinthifolius Raddi, was investigated in a quarantine laboratory as part of a classical biological control program against this invasive weed in Florida. Adults lived on average 6.8 ± 0.8 d, and a generation was completed in 43.6 d at a temperature of 22.0°C and a photoperiod of 12:12 (L:D) h. Peak egg production occurred 2 d after females eclosed from the pupal stage. Females deposited a maximum of 172 eggs, with an average daily maximum of 13.6 eggs. The durations of the egg, larval, and pupal stages were 5.9, 23.7 (five instars), and 12.0 d, respectively. Stage-specific life tables were constructed to calculate basic population statistics. Under laboratory conditions where predation and food supply were not limiting factors, a population of E. utilis was capable of multiplying its population by 1.17 times per day, and a doubling of the population would occur every 4.4 d. To date, 10 consecutive generations of E. utilis have been produced on potted Brazil peppertree plants in the laboratory. The potential effectiveness of F. uulis as a biological control agent of Brazilian peppertree in Florida was examined using Goeden's revision of the Harris scoring system. [ABSTRACT FROM AUTHOR]

Ocular tissue (conjunctiva and iris) was obtained from 12 adult African men with active ocular onchocerciasis and from nine age-matched persons from the same endemic region but without onchocercal infection. These tissues were examined immunohistologically and two major findings were noted. First, mild-to-moderate chronic inflammatory cellular infiltration was present in the conjunctiva of the onchocerciasis patients. T lymphocytes (CD3+) were the major inflammatory cells, and the T suppressor/cytotoxic (CD8+) subset was significantly increased in the ocular onchocerciasis patients (P < 0.03). Second, in the onchocerciasis patients, non-lymphoid cells of the conjunctiva and iris, such as vascular endothelium, pericytes and fibroblasts were in an activated slate, as shown by increased expression of Class M MHC antigens (P < 0.02, conjunctiva; P < 0.05, iris). These concomitant findings of lymphocyte infiltration and resident ceil activation indicate a dynamic state of localized host responsiveness presumably to the microfilarial parasites and their products in the anterior segments of the eyes of patients with ocular onchocerciasis. [ABSTRACT FROM AUTHOR]