Natural infection of Lutzomyia spp. with Leishmania was studied with the aid of the polymerase chain reaction (PCR) in Chaute, Lima, Perú, a locality endemic for Andean cutaneous leishmaniasis (uta). The PCR, with primers specific for the L. braziliensis complex, was applied to sandfly pools. Sandflies were sampled from April 1990 to May 1991 with CDC light traps in homes, and from near homes with a Shannon trap using protected human bait. Lu. verrucarum (4 pools) and Lu. peruenis (2 pools) from the anthropophilic collections, and Lu. verrucarum (2 pools) from indoors were found to be infected with Leishmania. The majority of infected sandflies were recorded mainly in April 1991 (4 pools), coinciding with the highest sandfly densities and the maximum number of new cases of uta (7). Non-infected sandflies were found from May to October 1990 and January to March 1991. Thus, these 2 sandfly species play a role in the spread of leishmaniasis among humans and other animals in Chaute.
Evidence that domestic dogs may act as reservoir hosts for cutaneous leishmaniasis in the Peruvian Andes is provided by the isolation, for the first time, from naturally infected dogs of parasites identified (by isoenzymes) as Leishmania peruviana. Leishmania parasites were isolated from nasal aspirates or biopsies from 5 (1.8%) of 279 asymptomatic dogs samples in endemic villages of the Peruvian Andes. In addition, Leishmania (Viannia) infections were identified in 15 (5.4%) of 276 nasal samples by the polymerase chain reaction (PCR) using subgenus-specific primers. Further circumstantial evidence for a reservoir role for dogs comes from the finding of a relatively high dog blood index among the sandfly vectors collected inside houses (29% for Lutzomyia peruensis and 17% for Lu. verrucarum). Possible wild mammal reservoir hosts for Andean cutaneous leishmaniasis were also detected in endemic villages. At least 8 species were identified among the 1266 small mammals trapped. Leishmania parasites were isolated from blood or skin biopsies taken from 2 (2.6%) of 78 Didelphis albiventris and 6 (1.2%) of 511 Phyllotis andinum. Three isolates were identified by isoenzymes as L. peruviana, and the other 5 were identified by PCR as Leishmania (Viannia) species. Leishmania (Viannia) infections were also identified by PCR directly on skin biopsies taken from 2 (2.8%) of 72 D. albiventris, 1 (0.2%) of 499 P. andinum, and 4 (2.6%) of 153 Akodon sp.
This study aimed to determine the aetiology of community-acquired pneumonia (CAP) by adding polymerase chain reaction (PCR) to conventional methods and to describe the clinical and laboratory features between patients with bacterial pneumonia (BP) and viral pneumonia (VP). Adults with CAP admitted from November 2009 to October 2010 were included. Demographics, comorbidities, severity and clinical features were recorded. Conventional microbiological methods included blood and sputum cultures, acute and convalescent serologic samples, and antigen urinary detection. New methods included multiplex PCR for Mycoplasma pneumoniae, Legionella pneumophila, Chlamydophila pneumoniae, Bordetella pertussis and 15 respiratory viruses. A total of 169 patients were included. Using conventional methods, we identified a pathogen in 51 % of cases. With PCR, up to 70 % of cases had an aetiological diagnosis. Forty-five patients had BP (34 %), 22 had VP (17 %) and 25 (19 %) had co-infection (BP and VP). Pneumococci and respiratory syncytial virus (RSV) were the most frequently identified pathogens. Procalcitonin (PCT) and C-reactive protein (CRP) median values were significantly higher in BP than in VP patients. Shaking chills, higher CURB score and shock were significantly more frequent in BP. A viral infection was identified in more than one-third of patients with CAP. Clinical and laboratory features could help to differentiate between VP and BP and to guide empirical therapy.
Following the examination of 53 Lutzomyia spp., seven Phlebotomus spp. and five Sergentomyia spp. (Diptera: Psychodidae) new observations are recorded on the presence of pheromone disseminating structures on the tergites of male phlebotomine sandflies. Descriptions are given of 11 of the species which include structures such as simple cuticular pores in craters, pores with emergent spines, and mammiform papules with or without spiny processes. Pheromone papule distribution on the tergites of Lutzomyia pessoai (Coutinho & Barretto) is plotted and gas chromatography and GC-mass spectroscopy have been used to demonstrate the presence of a diterpene compound similar to a sexual attractant pheromone observed in some L. longipalpis (Lutz & Neiva) populations.
The composition of the rectal gland secretion and volatiles emitted by female Queensland fruit fly, Bactrocera tryoni was investigated. Esters were found to be the main compounds in the gland extracts and headspace, while amides were the minor compounds in the gland extracts and headspace. Ethyl dodecanoate, ethyl tetradecanoate, ethyl (Z9)-hexadecenoate and ethyl palmitate were the main esters in the gland extracts, while ethyl dodecanoate and ethyl tetradecanoate were the main esters in the headspace. Four amides (N-(3-methylbutyl)acetamide), N-(2-methylbutyl)propanamide, N-(3-methylbutyl)propanamide, and N-(3-methylbutyl)-2-methylpropanamide were found in the gland extracts and the headspace. Among the amides, N-(3-methylbutyl)acetamide and N-(3-methylbutyl)propanamide were the main amides in the gland extracts and the headspace. Traces of three spiroacetals were found both in the gland extracts and in the headspace. (E,E)-2,8-Dimethyl-1,7-dioxaspiro[5.5]undecane, (E,E)-2-ethyl-8-methyl-1,7-dioxaspiro[5.5]undecane, (E,E)-2-propyl-8-methyl-1,7-dioxaspiro[5.5]undecane. All compounds found in the headspace were present in the extract of the rectal gland suggesting that the rectal gland is the main source of the headspace volatiles, whose function remains to be elucidated. This is the first comprehensive chemical analysis of the rectal gland secretions and volatiles of female B. tryoni, and further laboratory and field bioassays are required to determine the function of compounds identified in this study. Discovery of the same amides previously identified in the male rectal gland in the female rectal gland raises questions about the pheromonal role previously suggested for these compounds.
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