Environmental Risk Assessment of Drugs in Tropical Freshwaters Using Ceriodaphnia silvestrii as Test Organism.

In this study we evaluated the acute (immobility/mortality) and chronic (survival and reproduction) effects of the drugs caffeine, diclofenac sodium salt, ketoprofen, paracetamol and salicylic acid on the cladoceran Ceriodaphnia silvestrii. The environmental risks of these substances for tropical freshwaters were estimated from the risk quotient MEC/PNEC. Sensitivity in acute exposures varied up on the drug as follows: salicylic acid (EC50 = 69.15 mg L- 1) < caffeine (EC50 = 45.94 mg L- 1) < paracetamol (EC50 = 34.49 mg L- 1) < ketoprofen (EC50 = 24.84 mg L- 1) < diclofenac sodium salt (EC50 = 14.59 mg L- 1). Chronic toxicity data showed negative effects of the drugs on reproduction. Paracetamol and salicylic acid caused reduction in fecundity in concentrations starting from 10 mg L- 1 and 35 mg L- 1, respectively. Ketoprofen caused total inhibition at 5 mg L- 1. MEC/PNEC values were relatively low for all drugs. The risk was estimated as low or insignificant, except for caffeine, whose MEC/PNEC value was greater than 1 (moderate risk).

Refractory mucocutaneous leishmaniasis resolved with combination treatment based on intravenous pentamidine, oral azole, aerosolized liposomal amphotericin B, and intralesional meglumine antimoniate.

INTRODUCTION: Mucocutaneous leishmaniasis (MCL) is a complication of tegumentary leishmaniasis, causing potentially life-threatening lesions in the ear, nose, and throat (ENT) region, and most commonly due to Leishmania (Viannia) braziliensis. We report a case of relapsing MCL in an Italian traveler returning from Argentina. CASE DESCRIPTION: A 65-year-old Italian male patient with chronic kidney disease, arterial hypertension, prostatic hypertrophy, and type-2 diabetes mellitus was referred for severe relapsing MCL acquired in Argentina. ENT examination showed severe diffuse pharyngolaryngeal edema and erythema, partially obstructing the airways. A nasopharyngeal biopsy revealed a lymphoplasmacytic inflammation and presence of Leishmania amastigotes, subsequently identified as L. (V.) braziliensis by hsp70 PCR-RFLP analysis and sequencing. Despite receiving four courses of liposomal amphotericine B (L-AmB) and two courses of miltefosine over a 2-year period, the patient presented recurrence of symptoms a few months after the end of each course. After the patient was referred to us, a combined treatment was started with intravenous pentamidine 4 mg/kg on alternate days for 10 doses, followed by one dose per week for an additional seven doses, intralesional meglumine antimoniate on the nasal lesion once per week for six doses, oral azoles for three months, and aerosolized L-AmB on alternate days for three months. The treatment led to regression of mucosal lesions and respiratory symptoms. Renal function temporarily worsened, and the addition of insulin was required to maintain glycemic compensation after pentamidine discontinuation. CONCLUSIONS: This case highlights the difficulties in managing a life-threatening refractory case of MCL in an Italian traveler with multiple comorbidities. Even though parenteral antimonial derivatives are traditionally considered the treatment of choice for MCL, they are relatively contraindicated in cases of chronic kidney disease.The required dose adjustment in cases of impaired renal function is unknown, therefore the use of alternative drugs is recommended. This case was resolved with combination treatment, including aerosolized L-AmB, which had never been used before for MCL.

Impact of runoff water from an experimental agricultural field applied with Vertimec® 18EC (abamectin) on the survival, growth and gill morphology of zebrafish juveniles.

Edge-of-field waterbodies in tropical agroecosystems have been reported to be especially prone to pesticide contamination through runoff resulting from intensive irrigation practices and tropical rainfall. In the present study, the effects of runoff from an experimental agricultural field applied with Vertimec(®) 18EC (active ingredient: abamectin) on zebrafish were evaluated. To this end, the experimental field was applied with the Vertimec(®) 18EC dose recommended for strawberry crop in Brazil, whereas another field was treated with water only to serve as control. No effects of runoff water from either plot were recorded on survival. Water from the treated field led to increased growth and gill alterations. In general, these alterations were of the first and second degree, including proliferation of cells between the secondary lamellae, dilation at the lamellar apex, detachment of the respiratory epithelium and aneurism. These results confirm the high toxic potential of Vertimec(®) 18EC and provide evidence that environmental risks are likely to occur in areas subject to runoff containing this pesticide.

Detection, treatment, and prevention of carbapenemase-producing Enterobacteriaceae: recommendations from an International Working Group.

The prevalence of carbapenemase-producing Enterobacteriaceae (CPE) has increased during the past 10 years. Its detection is frequently difficult, because they do not always show a minimum inhibitory concentration (MIC) value for carbapenems in the resistance range. Both broth microdilution and agar dilution methods are more sensitive than disk diffusion method, Etest and automated systems. Studies on antimicrobial treatment are based on a limited number of patients; therefore, the optimal treatment is not well established. Combination therapy with two active drugs appears to be more effective than monotherapy. Combination of a carbapenem with another active agent--preferentially an aminoglycoside or colistin--could lower mortality provided that the MIC is ≤4 mg/l and probably ≤8 mg/l, and is administered in a higher-dose/prolonged-infusion regimen. An aggressive infection control and prevention strategy is recommended, including reinforcement of hand hygiene, using contact precautions and early detection of CPE through use of targeted surveillance.

Field and laboratory studies to assess the effects of Vertimec(®) 18EC on Daphnia similis.

The present study aimed to evaluate the interactions of the pesticide Vertimec(®) 18EC in aquatic ecosystems. In this respect, soil plots were contaminated with Vertimec(®) 18EC at the concentration indicated for strawberry crops (0.125L of solution m(-2)). After the contamination, torrential rainfall was simulated and the surface runoff was collected and transferred to mesocosm tanks in five treatments, run in triplicate: (1) control-C; (2) runoff from an uncontaminated plot-UR; (3) runoff from the plot contaminated with Vertimec(®) 18EC-CR; (4) direct application of Vertimec(®) 18EC in the water-V and (5) water samples gathered randomly to verify whether there was contamination between the mesocosms-RS. Water samples from these tanks were also submitted to ecotoxicological tests with Daphnia similis and analyses to evaluate the limnological characteristics, in five collection periods over 10 days (240h). Physical and chemical differences were observed in the water samples, mainly related to increased turbidity, suspended solids and nutrients (nitrogen and phosphate forms). Acute toxicity was observed for the direct application treatment for the entire experimental period, and in some periods for the CR treatment (from 48h to 168h). The results obtained suggest that the pesticide did not fully degrade during the study period (10 days) in the direct application treatment, demonstrating that the presence of other substances in the commercial formulation contribute to the maintenance of toxicity. This represents a potential risk for aquatic ecosystems in areas adjacent to where the chemical is applied.

Lethal effects of abamectin on the aquatic organisms Daphnia similis, Chironomus xanthus and Danio rerio.

Abamectin is used as an acaricide and insecticide for fruits, vegetables and ornamental plants, as well as a parasiticide for animals. One of the major problems of applying pesticides to crops is the likelihood of contaminating aquatic ecosystems by drift or runoff. Therefore, toxicity tests in the laboratory are important tools to predict the effects of chemical substances in aquatic ecosystems. The aim of this study was to assess the potential hazards of abamectin to the freshwater biota and consequently the possible losses of ecological services in contaminated water bodies. For this purpose, we identified the toxicity of abamectin on daphnids, insects and fish. Abamectin was highly toxic, with an EC(50) 48 h for Daphnia similis of 5.1 ng L(-1), LC(50) 96 h for Chironomus xanthus of 2.67 µg L(-1) and LC(50) 48 h for Danio rerio of 33 µg L(-1).