ANÁLISIS DE LA ENTOMOFAUNA BENÉFICA EN UN INVERNÁCULO EN TRANSICIÓN AGROECOLÓGICA EN EL CINTURÓN HORTÍCOLA DE LA PLATA

En La Plata (Argentina) hay algunos sistemas hortícolas bajo cubierta que no responden al modelo convencional; estos sistemas “agroecológicos” se caracterizan en general por mayor grado de diversidad vegetal, tanto cultivada como espontánea y un bajo uso de agroquímicos. Esto favorece la presencia de organismos benéficos como los carábidos y las arañas, al propiciar condiciones microambientales más heterogéneas. Algunos estudios señalaron que sistemas con una alta complejidad de microhábitats tienen una mayor abundancia, riqueza y estructuras de la comunidad más complejas que aquellos sistemas simplificados [1, 2]. El objetivo de este trabajo fue analizar la abundancia, riqueza, estructura y composición de la comunidad de carábidos y arañas en un invernáculo en transición agroecológica. Se muestreó un invernáculo con un manejo basado en principios agroecológicos. La entomofauna se recolectó con trampas “pitfall” durante la primavera-verano. Se colocaron 12 trampas distribuidas en tres transectas. En cuanto a la abundancia y riqueza se capturaron un total de 98 carábidos de 4 especies y 174 arañas de 5 familia. La estructura de la comunidad de carábidos y arañas es claramente escalonada (Figura 1). Las prácticas de manejo como el uso de agroquímicos y el laboreo del suelo, cambian las condiciones edáficas, eliminando o transformando el componente vegetal [1, 3] y alterando la abundancia, riqueza, estructura y composición de la comunidad de carábidos y arañas [1, 2]. En general, en este trabajo se pudo evidenciar que una mayor heterogeneidad de la vegetación determina las condiciones de hábitat [1, 3]. La presencia de varios cultivos y de vegetación espontánea, sumado al escaso laboreo y al bajo uso de agroquímicos, asegura un ambiente estable que favorece una mayor abundancia y riqueza de carábidos y arañas. Ambas estructuras del ensamble (carábidos y arañas) presentaron una dominancia de tipo escalonada entre las especies y familias presentes en el sistema, en las cuales, si bien existen variaciones en el grado de dominancia, las mismas son poco bruscas. Esto es compatible con sistemas de una importante diversidad y complejidad microambiental [2]. Las arañas constituyen un grupo predador por excelencia, ocupando exclusivamente este nivel trófico. Las Lycosidae mostraron una dominancia relativa de más del 50%, Hahniidae se mostró como dominante y Tetragnathidae mostró una dominancia muy importante. En cuanto a los carábidos se encontraron dos especies eudominantes: Scarites anthracinus y Aspidoglossa intermedia, una especie dominante: Paranortes cordicollis y una recedente: Loxandrus planicollis. Los carábidos hallados, independientemente de sus preferencias de hábitat, fueron de hábito predador, siendo las dos más dominantes además fosores. Las familias y especies presentes estuvieron en relación con las características de manejo del sistema. En estos sistemas “agroecológicos” el manejo de la biodiversidad vegetal y el manejo ecológico del suelo generan las condiciones propicias para la presencia de estos enemigos naturales (arañas y carábidos), y de esta manera se potencia el proceso de regulación biótica de plagas

MMP-9/RECK imbalance: a mechanism associated with high-grade cervical lesions and genital infection by Human Papillomavirus (HPV) and Chlamydia trachomatis

"Manuscript"BACKGROUND: Matrix metalloproteinases (MMP) are important enzymes in the tumor microenvironment associated with progression of cervical intraepithelial neoplasia (CIN) toward squamous cell carcinoma (SCC) of the cervix. However, the role of MMPs in the inflammatory process associated with Chlamydia trachomatis infection concomitant with the carcinogenic process driven by HPV has not yet been addressed. In the present study, we analyzed the state of the MMP-9-RECK axis in cervical carcinogenesis. METHODS: The levels of MMP-9 and RECK expression were analyzed by immunocytochemistry in liquid-based cytology samples from 136 women with high-grade cervical lesions (CIN2/CIN3) and cervical SCC diagnosed by LLETZ, and in 196 women without cervical neoplasia or CIN1. Real-time qPCR was performed to analyze expression of MMP-9 and RECK in 15 cervical samples. The presence of HPV-DNA and other genital pathogens was evaluated by PCR. RESULTS: We found a higher expression of MMP-9 [OR, 4.2; 95% confidence interval (CI), 2.2-7.8] and lower expression of RECK (OR, 0.4; 95% CI, 0.2-0.7) in women with CIN2/CIN3/SCC when compared with women from the control group (no neoplasia/CIN1). A statistically significant association was also found between MMP-9/RECK imbalance and infection by alpha-9 HPV and C. trachomatis. The prevalence of C. trachomatis infection was significantly higher in women with high-grade cervical disease (OR, 3.7; 95% CI, 1.3-11.3). CONCLUSIONS: MMP-9/RECK imbalance in cervical smears is significantly associated with high-grade cervical diseases and infection by alpha-9 HPV and C. trachomatis. IMPACT: MMP-9/RECK imbalance during cervical inflammation induced by C. trachomatis might play a role in HPV-mediated cervical carcinogenesis.This work was supported by Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP), numbers 2008/03232-1 (to L.L. Villa) and 2012/09746-2 (to M.G. Discacciati and S.S. Maria-Engler) and National Counsel of Technological and Scientific Development pharmaceutical innovation (CNPQ-INCT-if; to S.S. Maria-Engler)

Targeted molecular-genetic imaging and ligand-directed therapy in aggressive variant prostate cancer

Aggressive variant prostate cancers (AVPC) are a clinically defined group of tumors of heterogeneous morphologies, characterized by poor patient survival and for which limited diagnostic and treatment options are currently available. We show that the cell surface 78-kDa glucose-regulated protein (GRP78), a receptor that binds to phage-display-selected ligands, such as the SNTRVAP motif, is a candidate target in AVPC. We report the presence and accessibility of this receptor in clinical specimens from index patients. We also demonstrate that human AVPC cells displaying GRP78 on their surface could be effectively targeted both in vitro and in vivo by SNTRVAP, which also enabled specific delivery of siRNA species to tumor xenografts in mice. Finally, we evaluated ligand-directed strategies based on SNTRVAP-displaying adeno-associated virus/phage (AAVP) particles in mice bearing MDA-PCa-118b, a patient-derived xenograft (PDX) of castration-resistant prostate cancer bone metastasis that we exploited as a model of AVPC. For theranostic (a merging of the terms therapeutic and diagnostic) studies, GRP78-targeting AAVP particles served to deliver the human Herpes simplex virus thymidine kinase type-1 (HSVtk) gene, which has a dual function as a molecular-genetic sensor/reporter and a cell suicide-inducing transgene. We observed specific and simultaneous PET imaging and treatment of tumors in this preclinical model of AVPC. Our findings demonstrate the feasibility of GPR78-targeting, ligand-directed theranostics for translational applications in AVPC

The genomes of two key bumblebee species with primitive eusocial organization

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. Results: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. Conclusions: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation

Central Exercise Action Increases the AMPK and mTOR Response to Leptin

AMP-activated protein kinase (AMPK) and mammalian Target of Rapamycin (mTOR) are key regulators of cellular energy balance and of the effects of leptin on food intake. Acute exercise is associated with increased sensitivity to the effects of leptin on food intake in an IL-6-dependent manner. To determine whether exercise ameliorates the AMPK and mTOR response to leptin in the hypothalamus in an IL-6-dependent manner, rats performed two 3-h exercise bouts, separated by one 45-min rest period. Intracerebroventricular IL-6 infusion reduced food intake and pretreatment with AMPK activators and mTOR inhibitor prevented IL-6-induced anorexia. Activators of AMPK and fasting increased food intake in control rats to a greater extent than that observed in exercised ones, whereas inhibitor of AMPK had the opposite effect. Furthermore, the reduction of AMPK and ACC phosphorylation and increase in phosphorylation of proteins involved in mTOR signal transduction, observed in the hypothalamus after leptin infusion, were more pronounced in both lean and diet-induced obesity rats after acute exercise. Treatment with leptin reduced food intake in exercised rats that were pretreated with vehicle, although no increase in responsiveness to leptin-induced anorexia after pretreatment with anti-IL6 antibody, AICAR or Rapamycin was detected. Thus, the effects of leptin on the AMPK/mTOR pathway, potentiated by acute exercise, may contribute to appetite suppressive actions in the hypothalamus

Human Papillomaviruses and genital co-infections in gynaecological outpatients

<p>Abstract</p> <p>Background</p> <p>High grade HPV infections and persistence are the strongest risk factors for cervical cancer. Nevertheless other genital microorganisms may be involved in the progression of HPV associated lesions.</p> <p>Methods</p> <p>Cervical samples were collected to search for human Papillomavirus (HPV), bacteria and yeast infections in gynaecologic outpatients. HPV typing was carried out by PCR and sequencing on cervical brush specimens. <it>Chlamydia trachomatis </it>was identified by strand displacement amplification (SDA) and the other microorganisms were detected by conventional methods.</p> <p>Results</p> <p>In this cross-sectional study on 857 enrolled outpatients, statistical analyses revealed a significant association of HPV with <it>C. trachomatis </it>and <it>Ureaplasma urealyticum (</it>at high density) detection, whereas no correlation was found between HPV infection and bacterial vaginosis, <it>Streptococcus agalactiae</it>, yeasts, <it>Trichomonas vaginalis </it>and <it>U. urealyticum</it>. <it>Mycoplasma hominis </it>was isolated only in a few cases both in HPV positive and negative women and no patient was infected with <it>Neisseria gonorrhoeae</it>.</p> <p>Conclusion</p> <p>Although bacterial vaginosis was not significantly associated with HPV, it was more common among the HPV positive women. A significant association between HPV and <it>C. trachomatis </it>was found and interestingly also with <it>U. urealyticum </it>but only at a high colonization rate. These data suggest that it may be important to screen for the simultaneous presence of different microorganisms which may have synergistic pathological effects.</p

PCR colorimetric dot-blot assay and clinical pretest probability for diagnosis of Pulmonary Tuberculosis in Smear-Negative patients

<p>Abstract</p> <p>Background</p> <p>Smear-negative pulmonary tuberculosis (SNPTB) accounts for 30% of Pulmonary Tuberculosis (PTB) cases reported annually in developing nations. Polymerase chain reaction (PCR) may provide an alternative for the rapid detection of <it>Mycobacterium tuberculosis </it>(MTB); however little data are available regarding the clinical utility of PCR in SNPTB, in a setting with a high burden of TB/HIV co-infection.</p> <p>Methods</p> <p>To evaluate the performance of the PCR dot-blot in parallel with pretest probability (Clinical Suspicion) in patients suspected of having SNPTB, a prospective study of 213 individuals with clinical and radiological suspicion of SNPTB was carried out from May 2003 to May 2004, in a TB/HIV reference hospital. Respiratory specialists estimated the pretest probability of active disease into high, intermediate, low categories. Expectorated sputum was examined by direct microscopy (Ziehl-Neelsen staining), culture (Lowenstein Jensen) and PCR dot-blot. Gold standard was based on culture positivity combined with the clinical definition of PTB.</p> <p>Results</p> <p>In smear-negative and HIV subjects, active PTB was diagnosed in 28.4% (43/151) and 42.2% (19/45), respectively. In the high, intermediate and low pretest probability categories active PTB was diagnosed in 67.4% (31/46), 24% (6/25), 7.5% (6/80), respectively. PCR had sensitivity of 65% (CI 95%: 50%–78%) and specificity of 83% (CI 95%: 75%–89%). There was no difference in the sensitivity of PCR in relation to HIV status. PCR sensitivity and specificity among non-previously TB treated and those treated in the past were, respectively: 69%, 43%, 85% and 80%. The high pretest probability, when used as a diagnostic test, had sensitivity of 72% (CI 95%:57%–84%) and specificity of 86% (CI 95%:78%–92%). Using the PCR dot-blot in parallel with high pretest probability as a diagnostic test, sensitivity, specificity, positive and negative predictive values were: 90%, 71%, 75%, and 88%, respectively. Among non-previously TB treated and HIV subjects, this approach had sensitivity, specificity, positive and negative predictive values of 91%, 79%, 81%, 90%, and 90%, 65%, 72%, 88%, respectively.</p> <p>Conclusion</p> <p>PCR dot-blot associated with a high clinical suspicion may provide an important contribution to the diagnosis of SNPTB mainly in patients that have not been previously treated attended at a TB/HIV reference hospital.</p