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We conducted a study to investigate the relationship between exposure to cyanobacteria and microcystins and the incidence of symptoms in humans living in close proximity to lakes affected by cyanobacteria. The design was a prospective study of residents living around three lakes (Canada), one of which has a water treatment plant supplying potable water to local residents. Participants had to keep a daily journal of symptoms and record contact (full or limited) with the water body. Samples were collected to document cyanobacteria and microcystin concentrations. Symptoms potentially associated with cyanobacteria (gastrointestinal: 2 indices (GI1: diarrhea or abdominal pain or nausea or vomiting; GI2: diarrhea or vomiting or [nausea and fever] or [abdominal cramps and fever]); upper and lower respiratory tract; eye; ear; skin; muscle pain; headaches; mouth ulcers) were examined in relation with exposure to cyanobacteria and microcystin by using Poisson regression. Only gastrointestinal symptoms were associated with recreational contact. Globally, there was a significant increase in adjusted relative risk (RR) with higher cyanobacterial cell counts for GI2 (<20,000 cells/mL: RR=1.52, 95% CI=0.65-3.51; 20,000-100,000 cells/mL: RR=2.71, 95% CI=1.02-7.16; >100,000 cells/mL: RR=3.28, 95% CI=1.69-6.37, p-trend=0.001). In participants who received their drinking water supply from a plant whose source was contaminated by cyanobacteria, an increase in muscle pain (RR=5.16; 95% CI=2.93-9.07) and gastrointestinal (GI1: RR=3.87; 95% CI=1.62-9.21; GI2: RR=2.84; 95% CI=0.82-9.79), skin (RR=2.65; 95% CI=1.09-6.44) and ear symptoms (RR=6.10; 95% CI=2.48-15.03) was observed. The population should be made aware of the risks of gastrointestinal symptoms associated with contact (full or limited) with cyanobacteria. A risk management plan is needed for water treatment plants that draw their water from a source contaminated with cyanobacteria., (© 2013.)

High and low lines resulting from 30 generations of bidirectional selection for open-field activity have nonoverlapping distributions and more than a thirtyfold difference in mean activity. Open-field defecation scores of low-active lines are approximately 7 times higher than those of high-active lines, substantiating earlier reports of a large, negative genetic correlation between these characters. Since the selection experiment is replicated, other variables which are found to be reliably different among the high, control, and low lines are likely to be causally related to open-field activity; thus these selected lines of mice may be of use to other investigators.

Twenty immigrants from Mali and West Senegal were treated in Paris. Onchocerciasis was diagnosed by six skin snips using a Holth punch. Ivermectine was given in a single oral dose: ten patients were given 50 mcg/kg, three were given 75 mcg/kg and seven received 100 mcg/kg. No patients had ocular symptoms. The results were as follows: Pruritus disappeared rapidly in 9 out of 11 patients who itched before treatment. The microfilarial load decreased rapidly, especially in cases treated with 75 mcg/kg and 100 mcg/kg as all patients tested on day 60 were negative. Clinical signs of the Mazzotti reaction and ocular reactions were not observed following the treatment. Pruritus was briefly aggravated in only two patients. No cardiovascular, hematological, hepatic or renal toxicity was noted.