Systematic review on the biology, ecology, genetic diversity and parasite transmission potential of Panstrongylus geniculatus (Latreille 1811) in Latin America

Panstrongylus geniculatus (Latreille, 1811) is the triatomine with the largest geographic distribution in Latin America. It has been reported in 18 countries from southern Mexico to northern Argentina, including the Caribbean islands. Although most reports indicate that P. geniculatus has wild habitats, this species has intrusive habits regarding human dwellings mainly located in intermediate deforested areas. It is attracted by artificial light from urban and rural buildings, raising the risk of transmission of Trypanosoma cruzi. Despite the wide body of published information on P. geniculatus, many knowledge gaps exist about its biology and epidemiological potential. For this reason, we analysed the literature for P. geniculatus in Scopus, PubMed, Scielo, Google Scholar and the BibTriv3.0 databases to update existing knowledge and provide better information on its geographic distribution, life cycle, genetic diversity, evidence of intrusion and domiciliation, vector-related circulating discrete taxonomic units, possible role in oral T. cruzi transmission, and the effect of climate change on its biology and epidemiology.

Lutzomyia longipalpis (Diptera: Psychodidae) Argentina-Bolivia border: new report and genetic diversity

American visceral leishmaniasis (AVL) has two main scenarios of transmission as follows: scattered cases in rural areas and urban outbreaks. Urban AVL is in active dispersion from the northeastern border of Argentina-Paraguay-Brazil to the South. The presence of Lutzomyia longipalpis was initially reported in urban environments in the northwestern border of the country. The presence of Lu. longipalpis, environmental variables associated with its distribution, and its genetic diversity were assessed in Salvador Mazza, Argentina, on the border with Bolivia. The genetic analysis showed high haplotype diversity, low nucleotide diversity, and low nucleotide polymorphism index. We discuss the hypothesis of an expanding urban population with introgressive hybridisation of older haplogroups found in their path in natural forest or rural environments, acquiring a new adaptability to urban environments, and the possibility of changes in vector capacity.

Dengue virus infection induces chromatin remodeling at locus AAEL006536 in the midgut of Aedes aegypti / La infección por virus dengue induce remodelación de la cromatina en el locus AAEL006536 en el intestino medio de Aedes aegypti

Abstract: Objective: To identify and characterize Aedes aegypti's AAEL006536 gene proximal upstream cis-regulatory sequences activated by dengue virus infection. Materials and methods: A. aegypti Rockefeller strain mosquitoes were blood fed or infected with dengue virus 2. Open chromatin profiling was then carried out in pools of midguts from each group of mosquitoes. Results: The proximal upstream region does not contain open chromatin sites in the midguts of blood-fed mosquitoes as detected by FAIRE-qPCR. In contrast, two cis-regulatory sites were identified in the same upstream region of dengue virus-infected mosquito midguts. The distal sequence contains STAT-, REL- and C/EBP-type transcription factor binding sites. Conclusion: The activation of two proximal cis-regulatory sequences, induced by dengue virus infection, is mediated by chromatin remodeling mechanisms. Binding sites suggest a dengue virus infection-induced participation of immunity transcription factors in the up-regulation of this gene. This suggests the participation of the AAEL006536 gene in the mosquito's antiviral innate immune response.

Resumen: Objetivo: Identificar y caracterizar las secuencias reguladoras activadas por la infección por virus dengue en la región proximal del gen AAEL006536 de Aedes aegypti. Material y métodos: Mosquitos de la cepa Rockefeller de A. aegypti se infectaron con virus dengue o se alimentaron con sangre. Se obtuvieron los perfiles de cromatina abierta del locus en los intestinos de cada uno de los grupos. Resultados: Se identificaron dos sitios reguladores solo en los intestinos de mosquitos infectados por virus dengue. El sitio distal contiene sitios de unión a factores de transcripción tipo REL, STAT y C/EBP. Conclusiones: La activación de dos sitios reguladores proximales está mediada por la remodelación de la cromatina. Los sitios de unión a factores de transcripción en el sitio regulador distal sugieren la participación de las vías de inmunidad en la regulación del gen. Esto sugiere la participación de este gen en la respuesta inmune del mosquito frente a la infección viral.

Phylogenetic signal at the Cytb-SertRNA-IG1-ND1 mitochondrial region in Anopheles (Kerteszia) neivai Howard, Dyar & Knab, 1913 / Señal filogenética de la región Cytb- SertRNA -IG1-ND1 en Anopheles (Kerteszia) neivai Howard, Dyar & Knab, 1913

Abstract Introduction: Mitochondrial DNA has proven its utility for the study of insect evolution. Genes such as cytochrome b (Cytb) and the transfer gene for serine (SertRNA) can be used to compare closely related organisms. Objective: The phylogenetic utility of Cytb-SertRNA-IG1-ND1 was tested for polymorphisms, and secondary structure modeling in SertRNA was done to detect possible cryptic species in Anopheles neivai. Materials and methods: Specimens from Colombia, Guatemala, and the type locality in Panamá were collected and sequenced for specimen comparison based on DNA polymorphisms, and secondary structure modeling for the SertRNA gene. Results: Thirty-six sequences for A. neivai and A. pholidotus were obtained. Conclusions: Polymorphic variants were detected in A. neivai for Cytb-SertRNA-IG1- ND1. Despite this variation in A. neivai, cryptic species could not be detected.

Resumen Introducción. El ADN mitocondrial ha demostrado su utilidad para el estudio de la evolución en los insectos. Existen algunos genes mitocondriales como el citocromo b (Cytb) y el gen de transferencia para el aminoácido serina (SertRNA) que pueden usarse en el diagnóstico de especies estrechamente relacionadas. Objetivo. Explorar la utilidad filogenética de la región Cytb-SertRNA-IG1-ND1 para detectar posibles especies crípticas en Anopheles neivai. Materiales y métodos. Se recolectaron especímenes en Colombia, Guatemala y en la localidad tipo en Panamá, los cuales se secuenciaron y se compararon mediante el polimorfismo de ADN en toda la región y mediante la simulación de estructuras secundarias del gen SertRNA. Resultados. Se obtuvieron las secuencias de especímenes de A. neivai (34) y A. pholidotus (2). Conclusiones. Se detectaron algunos polimorfismos para la regiónCytb-SertRNA-IG1-ND1 en A. neivai, pero no así especies crípticas.

The current status of the Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) species complex

Lutzomyia longipalpis s.l. is a complex of sibling species and is the principal vector of American visceral leishmaniasis. The present review summarises the diversity of efforts that have been undertaken to elucidate the number of unnamed species in this species complex and the phylogenetic relationships among them. A wide variety of evidence, including chemical, behavioral and molecular traits, suggests very recent speciation events and complex population structure in this group. Although significant advances have been achieved to date, differential vector capacity and the correlation between structure of parasite and vector populations have yet to be elucidated. Furthermore, increased knowledge about recent epidemiological changes, such as urbanisation, is essential for pursuing effective strategies for sandfly control in the New World.

In vitro observation of haemolymph melanization and melanin-related biosynthesis enzyme genes in silkworm, Bombyx mori / 生物工程学报

The observation statistics suggested that the haemolymph melanization speed of larvae became fast and the growth inhibition of Escherichia coli was strong as the quantities of feeding on mulberry leaves increased. The RT-PCR result showed that the mRNA expressions of melanin biosynthesis enzyme BmTan, BmPo-1, BmYellow-f and BmDdc were high in the haemolyph of 5 L 3 d larvae. The qPCR analysis showed Bmtan, Bmddc, Bmyellow, Bmebony and Bmblack, especially Bmddc expression were significantly higher in black disease larvae than in normal larvae. Compared with control, Ddc inhibitors drastically inhibited the lipopolysaccharide-induced haemolymph melanization. In addition, the content of Dopa and Dopamine markedly rose after E. coli injection. These indicated that haemolymph melanization was linked to immune defenses and Bmddc may play a role in melanization response of haemolymph immune in silkworm.

A nuclear ribosomal DNA pseudogene in triatomines opens a new research field of fundamental and applied implications in Chagas disease

A pseudogene, designated as "ps(5.8S+ITS-2)", paralogous to the 5.8S gene and internal transcribed spacer (ITS)-2 of the nuclear ribosomal DNA (rDNA), has been recently found in many triatomine species distributed throughout North America, Central America and northern South America. Among characteristics used as criteria for pseudogene verification, secondary structures and free energy are highlighted, showing a lower fit between minimum free energy, partition function and centroid structures, although in given cases the fit only appeared to be slightly lower. The unique characteristics of "ps(5.8S+ITS-2)" as a processed or retrotransposed pseudogenic unit of the ghost type are reviewed, with emphasis on its potential functionality compared to the functionality of genes and spacers of the normal rDNA operon. Besides the technical problem of the risk for erroneous sequence results, the usefulness of "ps(5.8S+ITS-2)" for specimen classification, phylogenetic analyses and systematic/taxonomic studies should be highlighted, based on consistence and retention index values, which in pseudogenic sequence trees were higher than in functional sequence trees. Additionally, intraindividual, interpopulational and interspecific differences in pseudogene amount and the fact that it is a pseudogene in the nuclear rDNA suggests a potential relationships with fitness, behaviour and adaptability of triatomine vectors and consequently its potential utility in Chagas disease epidemiology and control.

Cambios genéticos temporales y microgeográficos de Aedes aegypti en Medellín, Colombia / Microgeographic and temporal genetic changes of Aedes aegypti from Medellín, Colombia

Introducción. Las poblaciones de Aedes aegypti pueden experimentar cambios en cuanto a su abundancia y diversidad genética y, con ello, su potencial evolutivo para responder al control vectorial. El conocimiento de los cambios en la variación genética a escala espacio-temporal, permite entender mejor la epidemiología del dengue y contribuye al diseño adecuado y oportuno de estrategias antivectoriales. Objetivo. Evaluar los cambios genéticos, la diversidad y el flujo génico en seis poblaciones microgeográficas de Ae. aegypti en Medellín en diferentes períodos epidemiológicos del dengue. Materiales y métodos. En 255 especímenes provenientes de seis barrios de Medellín, se evaluó la variación en la composición de los haplotipos mtDNA CO1 , así como la diversidad y la diferenciación genética en un período epidémico (2010) y en otro endémico (2012). Resultados. Se detectaron dos grupos de haplotipos muy diferenciados entre sí en ambos períodos, al igual que un haplotipo de alta frecuencia presente en todos los barrios. La mayor diversidad de haplotipos se registró en el 2012, pero la mayor diversidad de nucleótidos se presentó en el 2010. No se observó correlación significativa entre las distancias genéticas y geográficas. Conclusión. La composición genética de Ae. aegypti varía temporalmente sin un patrón predecible. La presencia de un haplotipo de gran frecuencia en ambos períodos podría ser indicio de una variación persistente adaptada al control vectorial. Sin embargo, la circulación simultánea de haplotipos CO1 muy diferenciados y compatibles con múltiples introducciones, sugiere que diversos acervos genéticos serían aptos para la transmisión. Estos resultados son compatibles con la dispersión del mosquito por efecto de actividades antrópicas, lo cual posibilitaría la diseminación rápida del virus durante epidemias en Medellín.

Introduction: Aedes aegypti populations may experience changes in abundance and genetic diversity in addition to changes in their evolutionary capability to respond to vector control. The knowledge on the changes in genetic variation on a spatio-temporal scale improves the epidemiological understanding of dengue and supports the appropriate and timely design of vector control strategies. Objective: To assess the genetic changes, diversity and gene flow in six microgeographical populations of Ae. aegypti in Medellín for different epidemiological periods of dengue. Materials and methods: A total of 255 specimens from six different neighborhoods in Medellín were used to assess variations in the CO1 mtDNA haplotype composition, diversity and genetic differentiation for an epidemic period (2010) and an endemic period (2012). Results: Two groups of highly differentiated haplotypes were present in both periods, and a high-frequency haplotype was assessed for all neighborhoods. The highest haplotype diversity was recorded in 2012, but the maximum nucleotide diversity was recorded in 2010. No significant correlation between genetic and geographic distances was observed. Conclusions: The genetic composition of Ae. aegypti varies over time without a predictable pattern. In addition, the presence of a high-frequency haplotype in both periods could indicate a persistent variation adapted to vector control. However, the simultaneous movement of highly differentiated CO1 haplotypes compatible with multiple introductions suggests that different gene pools would be suitable for transmission. These results are consistent with mosquito dispersion due to human activities, which would enable the rapid spread of the virus during epidemics in Medellin.

Relationship between Neutrophil-To-Lymphocyte Ratio and Electrocardiographic Ischemia Grade in STEMI / Associação entre a Relação Neutrófilos/Linfócitos e o Grau de Isquemia Eletrocardiográfica no IAMEST

Background: Neutrophil-to-lymphocyte ratio (NLR) has been found to be a good predictor of future adverse cardiovascular outcomes in patients with ST-segment elevation myocardial infarction (STEMI). Changes in the QRS terminal portion have also been associated with adverse outcomes following STEMI. Objective: To investigate the relationship between ECG ischemia grade and NLR in patients presenting with STEMI, in order to determine additional conventional risk factors for early risk stratification. Methods: Patients with STEMI were investigated. The grade of ischemia was analyzed from the ECG performed on admission. White blood cells and subtypes were measured as part of the automated complete blood count (CBC) analysis. Patients were classified into two groups according to the ischemia grade presented on the admission ECG, as grade 2 ischemia (G2I) and grade 3 ischemia (G3I). Results: Patients with G3I had significantly lower mean left ventricular ejection fraction than those in G2I (44.58 ± 7.23 vs. 48.44 ± 7.61, p = 0.001). As expected, in-hospital mortality rate increased proportionally with the increase in ischemia grade (p = 0.036). There were significant differences in percentage of lymphocytes (p = 0.010) and percentage of neutrophils (p = 0.004), and therefore, NLR was significantly different between G2I and G3I patients (p < 0.001). Multivariate logistic regression analysis revealed that only NLR was the independent variable with a significant effect on ECG ischemia grade (odds ratio = 1.254, 95% confidence interval 1.120–1.403, p < 0.001). Conclusion: We found an association between G3I and elevated NLR in patients with STEMI. We believe that such an association might provide an additional prognostic value for risk stratification in patients with STEMI when combined with standardized risk scores. .

Fundamento: A relação neutrófilos/linfócitos (N/L) tem sido descrita como boa preditora de eventos cardiovasculares adversos futuros em pacientes com infarto agudo do miocárdio com elevação do segmento ST (IAMEST). Mudanças na porção terminal do complexo QRS também têm sido associadas a eventos adversos após IAMEST. Objetivo: Investigar a associação entre o grau de isquemia no ECG e a relação N/L em pacientes com IAMEST para determinar fatores de risco convencionais adicionais na estratificação precoce de risco. Métodos: Pacientes com IAMEST foram investigados. O grau de isquemia foi analisado a partir do ECG obtido à admissão. A contagem de leucócitos e seus subtipos foi realizada a partir de hemograma automatizado. De acordo com o grau de isquemia presente no ECG de admissão, os pacientes foram classificados em dois grupos, isquemia grau 2 (IG2) e isquemia grau 3 (IG3). Resultados: Pacientes com IG3 apresentaram valores médios significativamente menores de fração de ejeção do ventrículo esquerdo do que os pacientes com IG2 (44,58 ± 7,23 versus 48,44 ± 7,61; p = 0,001). Como esperado, a taxa de mortalidade intra-hospitalar aumentou proporcionalmente com o aumento no grau de isquemia (p = 0,036). Houve diferenças significativas nas porcentagens de linfócitos (p = 0,010) e de neutrófilos (p = 0,004) e, portanto, a relação N/L diferiu significativamente entre pacientes com IG2 e IG3 (p < 0,001). À análise de regressão logística multivariada, apenas a relação N/L emergiu como variável independente com efeito significativo sobre o grau de isquemia no ECG (odds ratio = 1,254; intervalo de confiança de 95% 1,120-1,403; p < 0,001). Conclusão: Nós encontramos uma associação entre IG3 e relação N/L aumentada em pacientes com IAMEST. Acreditamos que esta associação possa oferecer um valor prognóstico adicional para estratificação de risco em pacientes com IAMEST quando usado em combinação com escores de risco padronizados. .

Total clipless cholecystectomy by means of harmonic sealing / Colecistectomia laparoscópica totalmente ultrassônica sem uso de clipe metálico

BACKGROUND: In traditional laparoscopic cholecistectomy, the cystic duct and artery are commonly closed by metallic clips just before their division. Although the placement of these clips for occluding cystic artery and duct can be considered safe, biliary leaks and bleeding may occur especially by its dislodgement. AIM: To report a prospective case-series in total clipless cholecystectomy by means of harmonic shears for closure and division of the artery and cystic duct as well removal of the gallbladder from the liver. METHODS: Was evaluate a series of 125 patients who underwent laparoscopic cholecystectomy where the sealing and division of cystic artery and duct was carried out only by harmonic shears. The intact extracted gallbladder was submitted to a reverse pressure test for assessment of the technique safety by means of CO2 insuflation. RESULTS: The most common indication for surgery was gallstones. The mean operative time was 26 min and all gallbladders were dissected intact from the liver bed. There was no mortality and the overall morbidity rate was 0.8% with no hemorrhage or leaks. The reverse pressure test showed that all specimens support at least 36-mmHg of pressure without leaking. CONCLUSION: The harmonic shears is effective and safe in laparoscopic cholecystectomy as a sole instrument for sealing and division of the artery and cystic duct. The main advantages could be related to the safety and decreased operative time. .

RACIONAL: A colecistectomia laparoscópica na técnica tradicional oclui o ducto cístico e a artéria cística por clipes cirúrgicos, que podem se deslocar ou desprender no pós-operatório, possibilitando a ocorrência de fístula biliar ou hemorragia. OBJETIVO: Relato prospectivo de série de casos de colecistectomias laparoscópicas sem uso de clipe cirúrgico, sendo que a ligadura e secção da artéria cística e do ducto cístico foram realizadas por meio de bisturi ultrassônico. MÉTODO: Foram incluídos 125 pacientes submetidos à colecistectomia laparoscópica sem utilização de clipe cirúrgico metálico, onde a ligadura da artéria e do ducto cístico e também a remoção da vesícula biliar de seu leito hepático foram realizadas por meio de tesoura ultrassônica. Realizou-se teste de pressão reversa na vesícula biliar removida intacta do leito hepático para verificar a segurança da técnica. RESULTADOS: A principal indicação cirúrgica foi a colelitíase. O tempo cirúrgico médio foi de 26 min e todas as vesículas biliares foram retiradas intactas do leito hepático. Não houve mortalidade e a taxa global de morbidade foi de 0,8%, sem hemorragias ou fístulas. O teste de pressão reversa mostrou que o ducto cístico ocluído pelo bisturi harmônico suportou ao pelo menos 36 mmHg de pressão sem que ocorresse nenhum vazamento. CONCLUSÃO: O bisturi harmônico é eficaz e seguro em colecistectomias laparoscópicas eletivas como um instrumento único para ocluir e seccionar tanto a artéria cística quanto o ducto cístico. Vantagens podem ser apontadas ao método com relação a sua segurança e diminuição do tempo cirúrgico. .

Transcriptome responses to heat- and cold-stress in ladybirds (Cryptolaemus montrouzieri Mulasnt) analyzed by deep-sequencing

BACKGROUND: Changed temperature not only threaten agricultural production, but they also affect individual biological behavior, population and community of many insects, and consequently reduce the stability of our ecosystem. Insect's ability to respond to temperature stress evolved through a complex adaptive process, thus resulting in varied temperature tolerance among different insects. Both high and low extreme temperatures are detrimental to insect development since they constitute an important abiotic stress capable of inducing abnormal biological responses. Many studies on heat or cold tolerance of ladybirds have focused on measurements of physiological and biochemical indexes such as supercooling point, higher/lower lethal temperatures, survival rate, dry body weight, water content, and developmental duration. And studies of the molecular mechanisms of ladybird responses to heat or cold stress have focused on single genes, such as those encoding heat shock proteins, but has not been analyzed by transcriptome profiling. RESULTS: In this study, we report the use of Digital Gene Expression (DGE) tag profiling to gain insight into transcriptional events associated with heat- and cold-stress in C. montrouzieri. About 6 million tags (49 bp in length) were sequenced in a heat stress group, a cold stress group and a negative control group. We obtained 687 and 573 genes that showed significantly altered expression levels following heat and cold shock treatments, respectively. Analysis of the global gene expression pattern suggested that 42 enzyme-encoding genes mapped to many Gene Ontology terms are associated with insect's response to heat- and cold-stress. CONCLUSIONS: These results provide a global assessment of genes and molecular mechanisms involved in heat and cold tolerance.

Effect of curcumin on aged Drosophila melanogaster: a pathway prediction analysis / 中国结合医学杂志

<p><b>OBJECTIVE</b>To re-analyze the data published in order to explore plausible biological pathways that can be used to explain the anti-aging effect of curcumin.</p><p><b>METHODS</b>Microarray data generated from other study aiming to investigate effect of curcumin on extending lifespan of Drosophila melanogaster were further used for pathway prediction analysis. The differentially expressed genes were identified by using GeneSpring GX with a criterion of 3.0-fold change. Two Cytoscape plugins including BisoGenet and molecular complex detection (MCODE) were used to establish the protein-protein interaction (PPI) network based upon differential genes in order to detect highly connected regions. The function annotation clustering tool of Database for Annotation, Visualization and Integrated Discovery (DAVID) was used for pathway analysis.</p><p><b>RESULTS</b>A total of 87 genes expressed differentially in D. melanogaster melanogaster treated with curcumin were identified, among which 50 were up-regulated significantly and 37 were remarkably down-regulated in D. melanogaster melanogaster treated with curcumin. Based upon these differential genes, PPI network was constructed with 1,082 nodes and 2,412 edges. Five highly connected regions in PPI networks were detected by MCODE algorithm, suggesting anti-aging effect of curcumin may be underlined through five different pathways including Notch signaling pathway, basal transcription factors, cell cycle regulation, ribosome, Wnt signaling pathway, and p53 pathway.</p><p><b>CONCLUSION</b>Genes and their associated pathways in D. melanogaster melanogaster treated with anti-aging agent curcumin were identified using PPI network and MCODE algorithm, suggesting that curcumin may be developed as an alternative therapeutic medicine for treating aging-associated diseases.</p>

Un primer análisis de la investigación en México sobre los determinantes sociales de la salud: 2005-2012 / A first analysis of research on social determinants of health in Mexico: 2005-2012

Objetivo. Examinar la investigación hecha en México sobre los determinantes sociales de la salud (DSS) durante el periodo 2005-2012 con base en la caracterización del sistema nacional de investigación en salud y la producción científica sobre este tema. Material y métodos. Análisis en dos etapas: revisión documental de fuentes oficiales sobre investigación en salud en México y búsqueda sistemática de literatura sobre DSS. Resultados. Los DSS fueron mencionados en el Programa de Acción Específico de Investigación en Salud 2007-2012, pero no figuran en las estrategias y objetivos; en su lugar, se enfatizan primordialmente aspectos de infraestructura y administrativos. En el periodo se publicaron 145 artículos sobre DSS, cuyas temáticas más abordadas fueron "condiciones de salud", "sistemas de salud" y "nutrición y obesidad". Conclusiones. A pesar de que existe investigación en México sobre DSS, la instrumentación de esos hallazgos en políticas de salud no se ha implementado. El Programa Sectorial de Salud 2013-2018 representa una ventana de oportunidad para posicionar resultados de investigación que promuevan políticas de equidad en salud.

Objective. To examine the research on social determinants of health (SDH) produced in Mexico during the period 2005-2012, based on the characterization of the national health research system and the scientific production on this topic. Materials and methods. Two-stage analyses: Review of Mexican documents and official sources on health research and systematic bibliographic review of the literature on SDH. Results. Although SDH were mentioned in the Specific Action Plan for Health Research 2007-2012, they are not implemented in strategies and goals, as the emphasis is put mostly in infrastructure and administrative aspects of research. In the period studied, 145 articles were published on SDH topics such as health conditions, health systems and nutrition and obesity. Conclusions. In spite of the availability of research on SDH in Mexico, the operationalization of such findings into health policies has not been possible. The current Sectorial Program on Health 2013-2018 represents a window of opportunity to position research findings that promote health equity policies.

Cloning, identification and preliminary functional analysis of odorant receptor 7 gene of Aedes albopictus / 南方医科大学学报

<p><b>OBJECTIVE</b>To clone and identify olfactory receptor odorant receptor 7 (OR7) gene of Aedes albopictus and analyze its expression profile and calcium regulation function.</p><p><b>METHOD</b>RT-PCR was used to amplify the olfactory receptor OR7 gene of Ae. albopictus and OR7 expression was detected in different tissues and organs. The coding sequence of OR7 gene was cloned in eukaryotic expression vector pME18s, which was then transfected into HEK293 cells. The calcium callback function in response to odor molecule stimulation was analyzed by calcium imaging technique.</p><p><b>RESULTS</b>The OR7 gene of Ae. albopictus was cloned and sequence analysis showed that its coding region was 1395 bp. RT-PCR detected OR7 expression in the larvae, pupae and adult mosquitoes, especially in female mosquitos. Preliminary analysis of calcium callback function demonstrated the specific regulation of calcium absorption by OR7 in response to odor molecule stimulation.</p><p><b>CONCLUSION</b>The OR7 gene of Ae. albopictus has been cloned successfully. OR7 is highly expressed in female mosquitos and is capable of specific recognition of the odor molecules.</p>

Diferencias genéticas entre poblaciones de Aedes aegypti de municipios del norte de Colombia, con baja y alta incidencia de dengue / Genetic differences between populations of Aedes aegypti from municipalities in northern Colombia, with high and low dengue incidence

Introducción. Aedes aegypti es el principal vector del dengue en zonas urbanas. A pesar de su importancia epidemiológica, se desconoce la variabilidad genética de las poblaciones del vector en Colombia. Objetivo. Determinar la variabilidad genética del gen mitocondrial ND4 , que codifica para la subunidad 4 de la enzima NADH-deshidrogenasa, entre poblaciones de Ae. aegypti de los municipios de Sincelejo y Guaranda, donde se registra alta y baja incidencia de dengue, respectivamente. Materiales y métodos. A partir del material genético extraído de 36 hembras de Ae. aegypti , se determinó la secuencia parcial del gen mitocondrial ND4 y se estimaron los parámetros de diversidad de nucleótidos, diversidad haplotípica, estructura genética y flujo de genes entre las poblaciones de Sincelejo y Guaranda. También, se analizó la varianza molecular y se construyó una red haplotípica. Resultados. Se obtuvieron 36 secuencias de nucleótidos de 282 pb; éstas presentaron doce sitios polimórficos y se agruparon en diez haplotipos, dos presentes en ambas poblaciones, tres exclusivos de la población de Sincelejo y cinco de la población de Guaranda. Los estimadores de estructura genética ( F ST =0,15) y de flujo de genes ( Nm =1,40) evidencian diferenciación genética y un limitado intercambio de genes entre las poblaciones. Conclusión. Las poblaciones de Ae. aegypti de Sincelejo y Guaranda son genéticamente divergentes.

Introduction: Aedes aegypti is the principal vector of dengue in urban areas. Despite its epidemiological importance, the genetic variability of Colombian populations of this species is unknown. Objetive: To determine the genetic variability of mitocondrial gene ND4, which codes for subunit 4 of the enzyme NADH deshydrogenase, between populations of Ae. aegypti from municipalities of Sincelejo and Guaranda. The incidences of dengue reported from these two localities are high and low, respectively. Materials and methods: Genetic material extracted from 36 females of Ae. aegypti was used to determine the partial sequence of the mitocondrial gene ND4 as well as to estimate the parameters of nucleotidic and haplotypic diversities, genetic structure and gene flow between the Sincelejo and Guaranda populations. The molecular variance was also analysed and a haplotypic network constructed. Results: In all 36 nucleotide sequences of 282pb were obtained. These presented 12 polymorphic sites and could grouped into 10 haplotypes, two of them present in both populations, three exclusive to the Sincelejo population and five to that of Guaranda. The estimators of genetic structure ( F ST = 0.15) and gene flow ( Nm = 1.40) are both indicative of genetic differentiation and a limited exchange of genes between the populations. Conclusions: The Sincelejo and Guaranda populations of Ae. aegypti are genetically divergent.

Isolation and expression profiling of transformer 2 gene in Aedes aegypti / 南方医科大学学报

<p><b>OBJECTIVE</b>To isolate, identify and analyze the sex-determining gene Transformer 2 (Aaetra2) of the major vector mosquito Aedes aegypti.</p><p><b>METHODS</b>tBLASTn program, RT-PCR and RACE methods were used to obtain the full-length cDNA of Aaetra2. Multiple alignments of nucleotide and amino acid sequences were conducted, and the different domains in tra2 protein were indentified. RT-PCR of the total RNA extracted from different tissue from the mosquitoes in different developmental stages was performed using specific primers.</p><p><b>RESULTS</b>Two genes, namely Aaetra2-α and Aaetra2-β, were identified in different supercontig locations. The multi-transcripts were expressed by means of alternative promoters or terminators. The different domains in tra2 protein were defined as RS-rich N-terminal region, RNA recognition motif-RRM, linker region, and RS-rich C-terminal region. Both Aaetra2-α and Aaetra2-β showed sustained expression throughout the developmental stages of Ae.aegypti, and in all the tissues without a sex specificity.</p><p><b>CONCLUSION</b>Aaetra2 gene has multiple isoforms and is mapped to multiple locations in the genome. Aaetra2 has conservative functional domains of the sex-determining gene tra2. For Ae.agypti, Aaetra2 shows the potential as a new target for release of insects carrying a dominant lethal (RIDL) technology based on transgenic mosquitoes.</p>

Low genetic diversity in Wolbachia-Infected Culex quinquefasciatus (Diptera: Culicidae) from Brazil and Argentina / Baixa diversidade genética em Culex quinquefasciatus (Diptera: Culicidae) infectado por Wolbachia do Brasil e Argentina

Culex quinquefasciatus is a vector of human pathogens, including filarial nematodes and several viruses. Although its epidemiological relevance is known to vary across geographical regions, an understanding of its population genetic structure is still incipient. In light of this, we evaluated the genetic diversity of Cx. quinquefasciatus and Cx. pipiens x Cx. quinquefasciatus hybrids collected from nine localities in Brazil and one site in Argentina. We used mitochondrial genes cox1 and nd4, along with the coxA and wsp genes of the maternally-inherited Wolbachia endosymbiont. The nd4 fragment was invariant between samples, whilst cox1 exhibited four haplotypes that separated two types of Cx. quinquefasciatus, one clustered in southern Brazil. Low sequence diversity was generally observed, being discussed. Both Brazilian and Argentinian mosquitoes were infected with a single Wolbachia strain. As reported in previous studies with these populations, cox1 and nd4 diversity is not congruent with the population structure revealed by nuclear markers or alar morphology. Future Cx. quinquefasciatus research should, if possible, evaluate mtDNA diversity in light of other markers.

Culex quinquefasciatus é vetor de patógenos humanos, incluindo nematódeos filarídeos e vários vírus. Embora a sua relevância epidemiológica varie entre as diferentes regiões geográficas, o conhecimento da estrutura genética da população é ainda incipiente. Em vista disso, foram avaliados os níveis de diversidade genética de Cx. quinquefasciatus e de híbridos Cx. quinquefasciatus x Cx. pipiens de nove cidades do Brasil e em La Plata, na Argentina. Para os testes foram utilizados fragmentos dos genes mitocondriais cox1 e nd4, juntamente com coxA e wsp do endossimbionte Wolbachia, herdado maternalmente. O fragmento nd4 não apresentou variação entre as amostras, e o cox1 exibiu quatro haplótipos que separaram dois tipos de Cx. quinquefasciatus, com um deles agrupado no sul do Brasil. Os dados de sequência mostraram baixa diversidade, sendo esta discutida. Ambas as amostras de mosquitos brasileiros e argentinos estão infectados com uma única cepa de Wolbachia. A diversidade apresentada por nd4 e cox1 não é congruente com a estrutura da população revelada por marcadores nucleares e morfologia alar de estudos anteriores com estas mesmas populações. Pesquisas com Cx. quinquefasciatus devem, se possível, avaliar a diversidade por DNA mitocondrial na luz de outros marcadores.

Molecular phylogeny of the Myzorhynchella Section of Anopheles (Nyssorhynchus) (Diptera: Culicidae): genetic support for recently described and resurrected species

Phylogenetic relationships among species of the Myzorhynchella Section of Anopheles (Nyssorhynchus) were investigated using the nuclear ribosomal DNA second internal transcribed spacer (ITS2), the nuclear whitegene and mitochondrial cytochrome oxidase subunit I (COI) regions. The recently described Anopheles pristinus and resurrected Anopheles guarani were also included in the study. Bayesian phylogenetic analyses found Anopheles parvus to be the most distantly related species within the Section, a finding that is consistent with morphology. An. pristinus and An. guarani were clearly resolved from Anopheles antunesi and Anopheles lutzii, respectively. An. lutzii collected in the same mountain range as the type locality were found within a strongly supported clade, whereas individuals from the southern state of Rio Grande do Sul, tentatively identified as An. lutzii based on adult female external morphology, were distinct from An. lutzii, An. antunesi and from each other, and may therefore represent two new sympatric species. A more detailed examination of An. lutzii sensu latoalong its known geographic range is recommended to resolve these anomalous relationships.

Molecular divergence in the timeless and cpr genes among three sympatric cryptic species of the Anopheles triannulatus complex

Anopheles triannulatus s.l. is a malaria vector with a wide geographic distribution, ranging from Argentina-Nicaragua and Trinidad. Here we analysed sequences of two genes, timeless and cpr, to assess the genetic variability and divergence among three sympatric cryptic species of this complex from Salobra, central-western Brazil. The timeless gene sequences did not conclusively differentiate Anopheles halophylus and An. triannulatus species "C". However, a partial separation has been observed between these species and An. triannulatus s.s. Importantly, the analysis of the cpr gene sequences revealed fixed differences, no shared polymorphisms and considerable genetic differentiation among the three species of the An. triannulatus complex. The results confirm that An. triannulatus s.s., An. halophylus and An. triannulatus species C are distinct taxa, with the latter two likely representing a more recent speciation event.

Insights into the transcriptome of oenocytes from Aedes aegypti pupae

Oenocytes are ectodermic cells present in the fat body of several insect species and these cells are considered to be analogous to the mammalian liver, based on their role in lipid storage, metabolism and secretion. Although oenocytes were identified over a century ago, little is known about their messenger RNA expression profiles. In this study, we investigated the transcriptome of Aedes aegypti oenocytes. We constructed a cDNA library from Ae. aegypti MOYO-R strain oenocytes collected from pupae and randomly sequenced 687 clones. After sequences editing and assembly, 326 high-quality contigs were generated. The most abundant transcripts identified corresponded to the cytochrome P450 superfamily, whose members have roles primarily related to detoxification and lipid metabolism. In addition, we identified 18 other transcripts with putative functions associated with lipid metabolism. One such transcript, a fatty acid synthase, is highly represented in the cDNA library of oenocytes. Moreover, oenocytes expressed several immunity-related genes and the majority of these genes were lysozymes. The transcriptional profile suggests that oenocytes play diverse roles, such as detoxification and lipid metabolism, and increase our understanding of the importance of oenocytes in Ae. aegypti homeostasis and immune competence.