Artículos Científicos

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A new method for the detection of phospholipase A2 variants: Identification of isozymes in the venoms of newborn and adult Bothrops asper (terciopelo) snakes
(Elsevier B.V, 1988) Moreno, Edgardo; Alape, Alberto; Sánchez, Manuel; Gutiérrez, José María
E. Moreno, A. Alape, M. Sánchez and J. M. Gutiérrez. A new method for the detection of phospholipase A2 variants: identification of isozymes in the venoms of newborn and adult Bothrops asper (terciopelo) snakes. Toxicon 26, 363 - 371, 1988. - A new method for the identification of phospholipase A2 isozymes in snake venoms is described. The technique is based on the separation of the venom components by isoelectric focusing in agarose gels, transfer of the protein bands by diffusion onto nitrocellulose paper and detection of the phospholipolytic activity of the enzymes by a hemolytic assay either in agarose gels or by benzidine reaction on a solid matrix. Striking differences in the electrophoretic patterns of the phospholipase A2 isozymes between the Atlantic and Pacific venoms and between the newborn and adult venoms from Bothrops asper specimens were observed. The method allowed the detection of 9 different phospholipase A2 isozymes in the venom of adult Atlantic, 7 isozymes in the venom of adult Pacific, and 2 - 3 isozymes in the venoms of newborn specimens. Horse polyvalent antivenom varied in its capacity to neutralize the phospholipolytic activity of the different isozymes in the same venom and among different venoms.
Agreement among equine veterinarians and between equine veterinarians and inertial sensor system during clinical examination of hindlimb lameness in horses
(Equine Veterinary Journal Ltd, 2019-06-24) LEELAMANKONG, P.; MÂHLMANN, K.; LISCHER, C.; Estrada, Roberto
Background: Hindlimb lameness evaluation is known to be challenging. Experience is essential for the ability of equine veterinarians to detect lameness. Nevertheless, even an experienced veterinarian is still subject to bias. Objective lameness detecting methods have been established to aid veterinarians. Objectives: 1) To estimate the effect of experience on the interobserver agreement and the agreement between a body-mounted inertial sensor system (BMISS) and veterinarians on detecting hindlimb lameness, and 2) to estimate the agreement between the BMISS and highly experienced veterinarians on change in lameness after diagnostic analgesia. Study design: Cross-sectional study. Methods: Twenty-six horses with hindlimb lameness were evaluated in clinical conditions by clinicians and simultaneously measured by the BMISS. Videos of their lameness examination were recorded and shown to 13 veterinarians from three groups of varying experience for evaluation. The interobserver agreement and the agreement between veterinarians and the BMISS were calculated. Results: Interobserver agreement from all three groups was recorded as ‘fair’. The strength of agreement between veterinarians and BMISS was ‘fair’ for the highly experienced group, ‘slight to fair’ for the moderately experienced group and ‘slight’ in the inexperienced group. The BMISS and the highly experienced veterinarians declared a ‘strong’ agreement in assigning an improvement in lameness after diagnostic analgesia. Main limitations: Lameness evaluation through video viewing might be more challenging for some evaluators than live situations. Conclusions: Given the task of evaluating videos of horses trotting in a straight line, the more experienced veterinarians did not show more reliability than those with less experience. Due to 1) the moderate agreement between the BMISS and clinicians (highly experienced and moderately experienced) in the live clinical evaluation in determining hindlimb lameness, and 2) the strong association between the BMISS and highly experienced veterinarians in determining improvement of lameness after anaesthesia, therefore the use of the BMISS as a supporting tool for veterinarians is encouraged.
Analysis of the association between density of Helicobacter spp and gastric lesions in dogs
(American Journal of Veterinary Research, 2017-12) Suárez-Esquivel, Marcela; Alfaro-Alarcón, Alejandro; Guzman-Verri, Caterina; BARQUERO-CALVO, ELIAS
OBJECTIVE To evaluate the correlation between the density of native gastric Helicobacter spp and the presence of gastric lesions in dogs. ANIMALS 80 dogs of various breeds, sexes, and ages. PROCEDURES Gastroscopic and histologic examinations were performed for all dogs. Helicobacter spp were detected by combining evaluation of urease activity and results of bacteriologic culture, microscopic observation, and a 16S rRNA PCR assay. The density of Helicobacter-like organisms was evaluated with light microscopy by use of Warthin-Starry modified stain. Correlations were evaluated by use of the Spearman correlation analysis. RESULTS Gastritis was found in 55 of 80 dogs and classified as mild (n = 31), moderate (16), or severe (8). Of these 55 dogs, only 8 had clinical signs. Histologic examination revealed some degree of lymphocytic-plasmacytic infiltrate, mild eosinophilia, and neutrophilic inflammation in the lamina propria. Seventy-six dogs had positive results for Helicobacter spp. Helicobacter pylori DNA was not detected. Low density and homogeneous distribution of Helicobacter spp were observed in all gastric zones. CONCLUSIONS AND CLINICAL RELEVANCE A significant correlation between density of Helicobacter spp and gastroscopic or histologic lesions was not detected. These findings supported the contention that there is no correlation between general Helicobacter spp density or numbers and gastritis in dogs.
Anthelmintic resistance in commercial sheep farms in Costa Rica
(Elsevier B.V., 2021) Castro Arnáez, Isabel Cristina; Álvarez Calderón, Victor; Soto Barrientos, Natalia; Montenegro Hidalgo, Victor Manuel; Vargas Leitón, Bernardo
Forty-eight commercial sheep farms were sampled between the years 2017 and 2019 to evaluate the percentage of reduction of the three families of broad-spectrum anthelmintic drugs available in Costa Rica - benzimidazoles (albendazole), macrocyclic lactones (ivermectin) and imidazothiazoles (levamisole) - in grazing animals by using the fecal egg count reduction test. Animals were selected based on their egg per gram counts after their fecal samples were processed by a modified McMaster technique. The remaining fecal samples were taken to the laboratory for fecal culture and larval identification. The prevalence of farms with albendazole resistance was 100%, ivermectin 96% and levamisole 17%. Seven (n = 47) farms resulted with triple resistance, 39 with double and 1 farm was resistant to 1 AH tested. Haemonchus spp. was the most commonly isolated parasite in pre- and post-treatment larval culture. This is the first report of Oesophagostomum spp. and Teladorsagia sp. resistant to albendazole, Oesophagostomum spp., Teladorsagia sp., Chabertia sp. and Cooperia sp. resistant to ivermectin, and the presence of strains of Haemonchus spp. and Trichostrongylus sp. resistant to the 3 anthelmintics tested. The results of this study demonstrate that anthelmintic resistance is widespread, particularly in Haemonchus spp., and that the major drugs available in the country have lost much of their effectiveness against sheep nematodes.
Antimicrobial resistance and genetic diversity of Campylobacter spp. isolated from broiler chicken at three levels of the poultry production chain in Costa Rica
(International Association for Food Protection, 2021-07-29) Lazo Láscarez, Sabrina; Zumbado Gutiérrez, Leana; Duarte-Martínez , Francisco; ROMERO-ZUÑIGA, JUAN JOSE; Arias Echandi, María Laura; MUNOZ VARGAS, LOHENDY
Campylobacter spp. are considered the most common bacterial cause of human gastroenteritis, one of the four main causes of diarrheal disease worldwide, and they are one of the main foodborne pathogens causing hospitalizations and deaths. Here, 148 strains of Campylobacter spp. isolated from poultry at farms, processing plants, and retail stores in Costa Rica were examined for resistance to six antibiotics. An agar dilution test was used to determine the MIC and susceptibility profiles against doxycycline, ciprofloxacin, nalidixic acid, enrofloxacin, chloramphenicol, and erythromycin. In addition, a pulsed-field gel electrophoresis analysis was carried out to determine the genotype relatedness of a representative subset of the isolates. Approximately 136 (92%) of the 148 analyzed isolates showed resistance to the tested drugs. Nalidixic acid, ciprofloxacin, and enrofloxacin were the antibiotics for which resistance occurred most frequently (91.2, 85.8, and 85.8%, respectively); followed by doxycycline (25.0%), chloramphenicol (5.4%), and erythromycin (2.7%). The profile conferring only resistance to quinolones was the most frequently found, and only 2.0% of the isolates showed resistance to quinolones and macrolides simultaneously. Results showed a high frequency of resistant Campylobacter spp. strains and evidenced the distribution, selection, and circulation of resistant strains along the poultry chain from farms to consumers. Cross-contamination and resistance seem to play important roles in the dissemination of these strains at specific points of the poultry chain, even when control measures are being taken. The establishment of effective surveillance and control strategies represents an essential tool for foodborne diseases mitigation. The rational use of antibiotics, especially those still showing efficacy, should be a priority in both human and veterinary medicine to contain the progress of this phenomenon and its consequences.
ASGARD+: A New Modular Platform for Bacterial Antibiotic-Resistant Analysis
(Wiley Online Library, 2023-03-09) Montero Vargas, Maripaz; Saenz Rojas, Alex; Ramirez Carvajal, Lizbeth; Suárez-Esquivel, Marcela
ASGARD+ (Accelerated Sequential Genome-analysis and Antibiotic Re- sistance Detection) is a command-line platform for automatic identification of antibiotic-resistance genes in bacterial genomes, providing an easy-to-use interface to process big batches of sequence files from whole genome se- quencing, with minimal configuration. It also provides a CPU-optimization algorithm that reduces the processing time. This tool consists of two main pro- tocols. The first one, ASGARD, is based on the identification and annotation of antimicrobial resistance elements directly from the short reads using different public databases. SAGA, enables the alignment, indexing, and mapping of whole-genome samples against a reference genome for the detection and call of variants, as well as the visualization of the results through the construction of a tree of SNPs. The application of both protocols is performed using just one short command and one configuration file based on JSON syntax, which modulates each pipeline step, allowing the user to do as many interventions as needed on the different software tools that are adapted to the pipeline. The modular ASGARD+ allows researchers with little experience in bioinfor- matic analysis and command-line use to quickly explore bacterial genomes in depth, optimizing analysis times and obtaining accurate results. © 2023 Wiley Periodicals LLC.
Bactericidal activity of Lys49 and Asp49 myotoxic phospholipases A2 from Bothrops asper snake venom Synthetic Lys49 myotoxin II-(115−129)-peptide identifies its bactericidal region
(FEBS, 1998) Páramo, Leandro; Lomonte, Bruno; Pizarro Cerda, Javier; Bengoechea, José Antonio; Gorvel, Jean Pierre; Moreno, Edgardo
Mammalian group-II phospholipases A2 (PLA2) of inflammatory fluids display bactericidal properties, which are dependent on their enzymatic activity. This study shows that myotoxins II (Lys49) and III (Asp49), two group-II PLA2 isoforms from the venom of Bothrops asper, are lethal to a broad spectrum of bacteria. Since the catalytically inactive Lys49 myotoxin II isoform has similar bactericidal effects to its catalytically active Asp49 counterpart, a bactericidal mechanism that is independent of an intrinsic PLA2 activity is demonstrated. Moreover, a synthetic 13-residue peptide of myotoxin II, comprising residues 115-129 (common numbering system) near the C-terminal loop, reproduced the bactericidal effect of the intact protein. Following exposure to the peptide or the protein, accelerated uptake of the hydrophobic probe N-phenyl-N-naphthylamine was observed in susceptible but not in resistant bacteria, indicating that the lethal effect was initiated on the bacterial membrane. The outer membrane, isolated lipopolysaccharide (LPS), and lipid A of susceptible bacteria showed higher binding to the myotoxin II-(115-129)-peptide than the corresponding moieties of resistant strains. Bacterial LPS chimeras indicated that LPS is a relevant target for myotoxin II-(115-129)-peptide. When heterologous LPS of the resistant strain was present in the context of susceptible bacteria, the chimera became resistant, and vice versa. Myotoxin II represents a group-II PLA2 with a direct bactericidal effect that is independent of an intrinsic enzymatic activity, but adscribed to the presence of a short cluster of basic/hydrophobic amino acids near its C-terminal loop.
Biologic and genetic characteristics of Toxoplasma gondii isolates in free-range chickens from Costa Rica, Central America
(Elsevier B.V, 2006-02-23) Dubey, J.P.; Su, C.; Vindas Bolaños, Rafael; Sundar, N; Kwok, O.C.; Shen, S.K.; Morales, Juan Alberto; De Oliveira, Jaqueline
The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of T. gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gondii in 144 free-range chickens (Gallus domesticus) from Costa Rica was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT), and found in 60 (40.1%) of 144 chickens with titers of 1:5 in 16, 1:10 in 5, 1:20 in 2, 1:40 in 3, 1:80 in 5, and 1:160 or higher in 29. Tissues of all chickens were bioassayed for T. gondii in mice or cats. Hearts and brains of 52 chickens with titers of 1:5 or higher and 16 chickens with doubtful titers were pooled and bioassayed in mice. Tissues from 76 chickens with MAT titers of 1:10 or less were pooled and fed to three T. gondii-free cats. Fecal floats of cats were bioassayed orally in mice but were negative for T. gondii oocysts. T. gondii was isolated by bioassay in mice from 32 chickens with MAT titers of 1:10 or higher. All infected mice from 4 of the 32 isolates died of toxoplasmosis. Genotyping of these 32 isolates using polymorphisms at the loci SAG1, SAG2, SAG3, BTUB and GRA6 revealed five genotypes. Five isolates had type I alleles and one isolate had type III alleles at all loci. The rest 26 isolates contained the combination of type I and II or I and III alleles and were divided into three genotypes. None was found to have genotype II alleles at all five loci. This is the first report of genetic characterization of T. gondii isolates from Costa Rica, Central America.
Bone lesions caused by pythium insidiosum in a horse
(Oxford University Press, 1987-10-02) MENDOZA, L.; ALFARO, A. A.; VILLALOBOS, J.
A 5-year-old, female saddle horse developed a tumoral mass anterolaterally on the metacarpal region of its right front leg. Histopathological study showed hyaline, aseptate, broad hyphae in the sequestered coral-like necrotic masses. Radiographs revealed an extensive osteomyelitis with disorganized bone proliferation of the metacarpal bones, as well as exostosis of the distal radius and the proximal and distal row of carpal bones. The etiologic agent was detected histologically, isolated in culture and identified as Pythium insidiosum. Serological tests were positive. Immunotherapy was applied but no cure resulted. The horse was sacrificed and necropsy confirmed the X-ray findings.
Bovine Leukaemia‐virus infection in Costa Rica
(Blackwell Wissenschaft, 1995) BONILLA, J. A.; HERRERO, L.; Jiménez Sánchez, Carlos; Dolz, Gaby; Rodríguez, L.R.; Bolaños, E.; Cortéz Campos, María del Rocio; Moreno, Edgardo
The geographical distribution of bovine leukaemia‐virus (BLV)‐infected herds in Costa Rica and the isolation of BLV from cases of enzootic bovine leukosis are presented. It was found that BLV is prevalent throughout the country, affecting mostly dairy cattle (Bos taurus) located in the highlands around the central valley of Costa Rica. By contrast, beef cattle (Bos indicus) raised in the lowlands were affected to a lesser extent. One out of four isolates of BLV obtained from local cattle with lymphosarcomatous tumours was analysed and had similar physical, serological and biological characteristics to a reference strain of BLV isolated in the USA. However, different patterns of recognition of BLV‐protein p24 were observed among naturally infected cattle using the western‐blotting technique.
Breeding soundness evaluation of extensively managed bulls in Costa Rica
(Elsevier, 1999-02-17) Pérez, E.; Müller, E.; Soderquist, L; Rodrigues Martínez, H.; Chacón, Jorge
This paper describes the results of single breeding soundness evaluations (BSE) in 898 Bos indicus, Bos taurus and B. indicus x B. taurus bulls, 1 to 12 yr. old, extensively reared in different climatic regions of Costa Rica and representing approximately 2% of the total breeding bull population. Thirty-three percent (n= 296) of the bulls were classified as unsound for breeding owing to clinical problems (9.1%, n= 82), low scrotal circumference (SC) being the most common finding, followed by unsatisfactory sperm morphology (23.9%, n= 214). The prevalence of bulls unsound for breeding was lowest in Bos indicus (29%, P<0.01), intermediate in B. taurus (41%), and highest in B. indicus x B. taurus (48%). The percentages of abnormal sperm heads, acrosomes and midpieces tended to be higher in the ejaculates of bulls with softer testicular consistency (P<0.001), a long scrotum (P<0.01) or a low SC (P<0.05), and such bulls were more often classified as being unsound for breeding (P<0.05). Frequencies of sperm abnormalities were higher in bulls < 2 yr of age than in older males (P<0.01) and were highest in B. indicus x B. taurus bulls (P<0.001). The results confirm differences between species in their adaptability to a tropical environment and support earlier evidence of an association between SC, testicular consistency and scrotal length clinical parameters, and testicular function in bulls.
Canine brucellosis in Costa Rica reveals widespread Brucella canis infection and the recent introduction of foreign strains
(Elsevier, 2021-04-16) Foster, Jeffrey; Guzman-Verri, Caterina; Suárez Esquivel, Marcela; Ruiz Villalobos, Nazareth; Hidalgo Jara, Warren; Chacon Díaz, Carlos; Zúniga Pereira, Ana Mariel; Masís Mora, Mario; Fernández Fernández, Ericka; Hernández Mora, Gabriela; BARQUERO-CALVO, ELIAS; Chaves Olarte, Esteban; Thomson, Nicholas R.; Moreno, Edgardo
Brucellosis is a prevalent disease in Costa Rica (CR), with an increasing number of human infections. Close to half of homes in CR have one or more dogs, corresponding to ∼1.4 million canines, most of them in the Central Valley within or near the cities of San José, Heredia, and Alajuela. From 302 dog sera collected from this region, 19 were positive for Brucella canis antigens, and five had antibodies against smooth lipopolysaccharide, suggesting infections by both B. canis and other Brucella species. B. canis strains were isolated in the Central Valley from 26 kennel dogs and three pet dogs, all displaying clinical signs of canine brucellosis. We detected three recent introductions of different B. canis strains in kennels: two traced from Mexico and one from Panama. Multiple locus-variable number tandem repeats (MLVA-16) and whole-genome sequencing (WGSA) analyses showed that B. canis CR strains comprise three main lineages. The tree topologies obtained by WGSA and MLVA-16 just partially agreed, indicating that the latter analysis is not suitable for phylogenetic studies. The fatty acid methyl ester analysis resolved five different B. canis groups, showing less resolution power than the MLVA-16 and WGSA. Lactobacillic acid was absent in linages I and II but present in linage III, supporting the recent introductions of B. canis strains from Mexico. B. canis displaying putative functional cyclopropane synthase for the synthesis of lactobacillic acid are phylogenetically intertwined with B. canis with non-functional protein, indicating that mutations have occurred independently in the various lineages.
Canine mycotic keratoconjuntivitis caused by Acremonium kiliense
(Oxford University Press, 1985) Mendoza, Leonel; Donato, Anne; Padhye, Arvind
Mycotic keratoconjuntivitis caused by Acremonium kiliense in a German Shepherd bitch was diagnosed with the aid of laboratory tests. The dog presented with photophobia, tearing, corneal edema and reduction of the visual capacity. A thick white layer partially covered the right eye. The left eye showed irritation and small brown stains which were diagnosed as pigmentary keratitis. The initial treatment consisted of 2% yellow mercury oxide. Natamycin was used as final treatment. Seven days later, the natural brightness of the eye as well as the visual capacity were restored.
Chagas' disease: Risk factors for house infestation by Triatoma dimidiata, the major vector of Trypanosoma cruzi in Costa Rica
(The Johns Hopkins University School of Hygiene and Public Health., 1991) Starr, Mark D; Rojas, Julio C; Zeledon, Rodrigo; Hird, David W; Carpenter, Tim E
The reduction of domiciliary infestation by insect vectors, the key to controlling Chagas' disease, depends on identification of housing features associated with infestation. In this study, log-linear modeling was used to reanalyze data collected in 1964-1968 from 371 houses on characteristics potentially associated with infestation by the vector Triatoma dimidiata in a Costa Rican town with endemic Chagas' disease. A possible increased risk of infestation was observed for houses with a dirt floor (as compared with houses with another floor type) and for houses in poor sanitary condition (as compared with houses in good sanitary condition). A new risk factor for house infestation, the presence of roof tiles, was identified; the odds of infestation for houses with a tile roof were 2.4 times greater than the odds for houses with a galvanized metal roof. This significantly increased risk is probably due to the harboring of T. dimidiata in stacks of spare tiles next to house walls rather than to the tile roofs themselves.
Childhood leukaemia in Costa Rica, 1981-96
(Blackwell Science, 2002) Monge, Patricia; Wesseling, Catharina; Rodríguez, Ana Cecilia; Cantor, Kenneth P; Weiderpass, Elisabete; Reutfors, Johan; Ahlbom, Anders; Partanen, Timo
Childhood leukaemia incidence in Costa Rica during 1981-96, among the highest in the world, was analysed by histology, gender, birth year, time period of diagnosis, age at diagnosis and region. Numbers of cases were extracted from the database of the National Cancer Registry (RNT) of Costa Rica. Person-years at risk were calculated from census data and post-census population estimates. During the follow-up, 918 cases of leukaemia in children under 15 years (510 boys, 408 girls) were reported to the RNT (41% of all childhood malignancies), with an overall age-standardised incidence rate of 56 per million person-years. Acute lymphocytic leukaemia (ALL) represented 79% and acute non-lymphocytic leukaemia (ANLL) 16% of the cases, with rates of 43 and 9 per million person-years respectively. There were downward trends in incidence of total leukaemias, ALL and ANLL and 'not otherwise specified' (NOS) combined. Incidence of ALL was highest at 1-4 years of age in boys and girls, whereas ANLL peaked in girls during the first year of life. During 1991-96, the decrease in ALL was significant (P = 0.042). A multivariable Poisson regression model identified significant excesses of ALL for boys, for age groups 1-4 and 5-9 years and for three out of seven regions. Possible reasons for the high rates in Costa Rica are discussed.
Clinical and pathological findings of a sac-like formation in the tunica vaginalis of a nelore (Bos indicus) bull
(Blackwell, 2010) Chacón, Jorge; Berrocal, Alexis
Contents A seven-month-old purebred Nelore calf was diagnosed with a bilateral finger-shaped swelling although more prominent at the left side of the scrotum, located longitudinal and parallel to epididymis corpus. The finding was present from 7 months of age up to castration (performed at 25 months of age). Scrotal circumference, testicular and epididymis consistency and symmetry as well as seminal quality were normal during the follow-up period. The ultrasonographic appearance of the scrotal wall, pampiniform plexus, gonad and epididymis was normal. However, an anechoic region surrounded by a wall forming a sac-like structure with a blind end at its dorsal pole was seen on the swelling area. The examination of fluid aspirated from the saccular contents revealed the presence of mononuclear cells mainly from lymphocytic and histiocytic type as well as some loosing degenerated mesothelial cells. Gross examination at castration revealed a blind sac-like appendix derived from an evagination in the parietal layer of the tunica vaginalis. The structure of approximately 5.0 cm in length extended from the dorsal edge of the epididymis cauda. No adherences with surrounded tissues were observed. Histopathology of the sac wall showed a smooth inner surface composed by scarce mesothelial cells forming in some areas papillary-like projections protruding to the vaginal cavity. Underneath, a thick layer of fibrous tissue mixed with collagen fibres and mononuclear inflammatory cells were seen. The potential consequences of this saccular formation at an older age in a bull are unknown.
Deferred bulls: are cycles per conception and pregnancy rate determined by the type of spermiogramme deviation under natural mating?
(Elsevier, 2016) Navarro, Leonel; Chacón Calderón, Jorge
Deferred bulls undergo clinical deviations that could be transitory or have an uncertain potential fertility output. Data in Costa Rica showed no significant differences in conception rate (CR) between sound vs. deferred sires (DS), although it was 5% lower in the latter group (Navarro et al., Rep. Dom. Animals, 43, Suppl:3, 2008). Decreased potential fertility in (DS) could be concealed by using multiple sired breeding and/or when the mating season length allows many estrous cycles/cow. When impaired semen quality justified the deferred classification, the fertility output could be influenced by the type of spermiogramme abnormality. We aimed to determine whether the rate cycles/conception, as well as CR achieved by DS diverge according to the type of spermiogramme deviation under natural mating in tropical cattle farms.
Density dependence in a seasonal time series of the bamboo mosquito, Tripteroides bambusa (Diptera: Culicidae)
(Entomological Society of Canada, 2017) Hoshi, Tomonori; Imanishi-Kobayashi, Nozomi; Moji, Kazuhiko; Chaves, Luis Fernando
The bamboo mosquito, Tripteroides bambusa (Yamada) (Diptera: Culicidae), is a mosquito species ubiquitous across forested landscapes in Japan. During 2014 we sampled adult mosquitoes from May to November using a sweep net in Nagasaki, Japan. We recorded and managed our field data using Open Data Kit, which eased the overall process of data management before performing their statistical analysis. Here, we analyse the resulting biweekly time series of the bamboo mosquito abundance using time-series statistical techniques. Specifically, we test for density dependence in the population dynamics fitting the Ricker model. Parameter estimates for the Ricker model suggest that the bamboo mosquito is under density dependence regulation and that its population dynamics is stable. Our data also suggest the bamboo mosquito increased its abundance when temperature was more variable at our study site. Further work is warranted to better understand the linkage between the observed density dependence in the adults and the larvae of this mosquito species.
Detection of proteins antigenically related to Bothrops asper myotoxin in crotaline snake venoms
(Pergamon Press, 1987-03-05) Lomonte, Bruno; Moreno, Edgardo; Gutiérrez, José María
H. Loxtoxre, E, Moatnvo and J . M. GurtEsaez . Detation of proteins antigenically rdated to Bothrops riper myotoxin in crotaline snake venoms. Tadcon 25, 947 -953, 1987 . - The presence of componrnts antigenically related to Bothrop asps myotoxin was investigated by Western blotting and immunoeledrophoretic techniques . B. asps myotoxin is a non-glycosylated monomeric phospholipase A with a molecular weight by SDS-PAGE of 16,000 and isoeiectric point of pH 9.8 - 10 .0 . Results showed that proteins in the venoma of B. numntjjer, B. at7dntani, B. srhlegelü, B. picadoi, and A;kEsrrodon bllineatrrs were recognized by monospecific antibodies to B. riper myotoxin raised in rabbit and sheep . Western blotting indicated that cross-reacting proteins have a molecular weight of 16,000, with the extxpdon of that of B. pècadoi, which is of 24,000 mol. wt. However, immunadectrophoreais indicated that these componrnts are highly heterogeneous in charge, ranging from basic to adtüc proteins . The cross-reacting tomponent(s) present in newborn B. aspen venom has a different charge from that of the 'txluh-type' . Vrnoms from newborn sptximens :bowed an additional crow-reading band of 18,000 mol. wt. Mytxoxin is an abundant component in adult B. aspen venom. Myotoxin - antimyotoxin complexes had different dedrophoretic mobilities in rocket immunoeledrophoreais depending upon the species in which monoapecific immune sera were produced.
Detection of Rickettsia monacensis and Rickettsia amblyommatis in ticks collected from dogs in Costa Rica and Nicaragua
(Elsevier B.V, 2018-08-04) Springer, Andrea; Schicht, Sabine; Wölfel, Silke; Schaper, Sabine R.; Chitimia-Dobler, Lidia; Siebert, Susanne; Strube, Christina; Montenegro Hidalgo, Víctor Manuel
The neotropical climate of Central America provides ideal conditions for ticks, which may transmit several human pathogens, including spotted-fever group Rickettsia. Dogs may act as sentinels or reservoirs for human tick-borne diseases due to shared tick species. Here, ticks were collected from 680 client-owned dogs in Nicaragua and Costa Rica, and a total of 316 tick pools were investigated for Rickettsia infection by quantitative real-time PCR (qPCR) targeting the gltA gene. Subsequently, up to six further genomic targets (16S rDNA, gltA, sca4, ompA, ompB and the 23S-5S intergenic spacer) were investigated for Rickettsia species determination. The predominant tick species was Rhipicephalus sanguineus sensu lato (s.l.) (19.9% of dogs infested in Costa Rica, 48.0% in Nicaragua), followed by Ixodes boliviensis (3.1% in Costa Rica / none in Nicaragua) and Amblyomma ovale (4.8% in Costa Rica, 0.9% in Nicaragua). In total, 22 of 316 tick pools containing 60 of 1023 individual ticks were Rickettsia-positive as determined by qPCR, resulting in a minimum infection rate (MIR) of 2.2%. In detail, MIR in Rh. sanguineus s.l. was 0.7% (7/281 pools), in I. boliviensis 33.3% (12/13 pools) and in A. ovale 9.7% (3/22 pools). For 11 of 12 positive I. boliviensis pools and one of six positive Rh. sanguineus s.l. pools, the species could be determined as R. monacensis. R. amblyommatis was identified in one Rh. sanguineus s.l. pool from Costa Rica and one A. ovale pool from Nicaragua. Nine of 12 R. monacensis-positive tick pools were collected in San Rafael de Heredia, Costa Rica, indicating a high local occurrence in this area. This study supports recent evidence that R. monacensis is present on the American continent. Its high local occurrence among dog-asso ciated I. boliviensis, which may also parasitize humans, in Costa Rica gives cause for concern, as R. monacensis is also pathogenic to humans

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