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The scorpionism in Panama is notorious for the confluence and coexistence of buthid scorpions from the genera Centruroides and Tityus. This communication describes an overview of the larger representative toxic venom fractions from eight dangerous buthid scorpion species of Panama: Centruroides (C. granosus, C. bicolor, C. limbatus and C. panamensis) and Tityus (T. (A.) asthenes, T. (A.) festae, T. (T.) cerroazul and T. (A.) pachyurus). Their venoms were separated by HPLC and the corresponding sub-fractions were tested for lethality effects on mice and insects. Many fractions toxic to either mice or insects, or both, were found and have had their molecular masses determined by mass spectrometry analysis. The great majority of the lethal components had a molecular mass close to 7000 Da, assumed to be peptides that recognize Na+-channels, responsible for the toxicity symptoms observed in other buthids scorpion venoms. A toxic peptide isolated from the venom of T. pachyurus was sequenced by Edman degradation, allowing the synthesis of nucleotide probe for cloning the correspondent gene. The mature toxin based on the cDNA sequencing has the C-terminal residue amidated, contains 62 amino acid packed by 4 disulfide linkages, with molecular mass of 7099.1 Da. This same toxic peptide seems to be present in scorpions of the species T. pachyurus collected in 5 different regions of Panama, although the overall HPLC profile is quite different. The most diverse neurotoxic venom components from the genus Centruroides were found in the species C. panamensis, whereas T. cerroazul was the one from the genus Tityus. The most common neurotoxins were observed in the venoms of T. festae, T. asthenes and T. pachyurus with closely related molecular masses of 7099.1 and 7332 Da. The information reported here is considered very important for future generation of a neutralizing antivenom against scorpions from Panama. Furthermore, it will contribute to the growing interest in using bioactive toxins from scorpions for drug discovery purposes.

The present research evaluated the presence of Rickettsia spp. on ectoparasites of horses and dogs (using PCR techniques), and their sera (using immunofluorescence assay) in El Valle de Antón town in Panama. A total of 20 horses and 20 dogs were sampled, finding four species of ectoparasites on dogs (the ticks Rhipicephalus sanguineus, Amblyomma ovale, Amblyomma oblongoguttatum, and the flea Ctenocephalides felis), and two tick species on horses (Amblyomma cajennense and Dermacentor nitens). DNA of Rickettsia amblyommii was found in pools of A. cajennense, D. nitens, and R. sanguineus, while Rickettsia felis was detected in C. felis pools. Overall, 70% (14/20) and 65% (13/20) of the horses and dogs, respectively, were seroreactive (titer ≥ 64) to spotted fever group rickettsiae. Sera from six dogs and five horses reacted to R. amblyommii antigens with titers at least four-fold higher than those for the other antigens tested (Rickettsia bellii, Rickettsia parkeri, Rickettsia rhipicephali, R. felis, and R. rickettsii). These serological results, coupled with our molecular findings, suggest that these dogs and horses were infected by Rickettsia amblyommii. More studies need to be realized afford to identify the Rickettsia species responsible for other serological and molecular positive results, and their ecological importance.

Background To report the first case of an anaphylactic shock, almost lethal, in the Republic of Panama, produced by ingestion of pancakes contaminated by mites. Methods A 21 year-old male patient was evaluated due to an anaphylactic shock after the ingestion of pancakes, eggs and milk. The patient had a background of a moderate allergic rhinitis. Not asthma. Skin prick test was performed on the patient with standardized extract of mites and food items, including, flour, milk and egg. After twenty minutes the results were read and considered positive since the wheal was 2 mm larger than the control (histamine 1 mg/mL). The Total IgE was determined by the chemiluminescence method. The determination of the specific IgE for mites and food was performed by the enzyme immunoassay technique. The counting and identification of the mites in the pancake samples that were eaten by the patient were placed in a microscopic slide using a Hoyer medium and analyzed in a stereomicroscope. Results The skin prick test performed was considered positive for Blomia tropicalis, Dermatophagoides pteronyssinus and negative for flour, milk and egg. The total IgE was increased and the specific IgE resulted positive for Dermatophagoides pteronyssinus and Blomia tropicalis, but negative for flour, egg and milk. The microscopic examination of the pancake wheat showed 3 different species of mites: Blomia tropicalis, Blomia sp. and Dermatophagoides pteronyssinus, the first one in major proportion. Conclusions The anaphylactic shock of the patient was produced by the ingestion of a commercial pancake contaminated by mites to which the patient was sensitized. Flour kept in open containers becomes a fertile ground for the growth of mites in tropical climates. Allergic patients should be warned of the danger of anaphylaxis in such conditions.