76 research outputs found

    Agronomic Performance and Genetic Variability of \u3cem\u3ePanicum Maximum\u3c/em\u3e Accessions in the Cerrado of Federal District, Brazil

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    In the last three decades, the Brazilian Savanna (locally called Cerrado ) became the most important beef cattle production region in Brazil. Around 90% of all beef produced in the region comes from pasture-based systems. Intensively-managed and fertilised Panicum maximum pastures can be highly productive and economic. As a result, farmers are demanding new P. maximum cultivars for using in well-fertilised pastures or in crop-pasture rotation systems. This study aimed to evaluate the agronomic performance and the genetic variability of P. maximum accessions in the Brazilian Cerrado

    E-cadherin expression and bromodeoxyuridine incorporation during development of ovarian inclusion cysts in age-matched breeder and incessantly ovulated CD-1 mice

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    BACKGROUND: Female CD-1/Swiss Webster mice subjected to incessant ovulation for 8 months and 12-month breeder mice both developed ovarian inclusion cysts similar to serous cystadenomas. The majority of cysts appeared to be dilated rete ovarii tubules, but high ovulation number resulted in more cortical inclusion cysts. We hypothesized that comparison of inclusion cyst pathology in animals of the same age, but with differences in total lifetime ovulation number, might allow us to determine distinguishing characteristics of the two types of cyst. METHODS: Ovaries from breeder mice (BR) or females subjected to incessant ovulation (IO) were compared at 6-, 9- and 12-months of age. Ovaries were serially sectioned and cysts characterized with regard to location and histology, E-cadherin immunoreactivity and rates of BrdU incorporation. RESULTS: Inclusion cysts developed with age in BR and IO ovaries. The majority of cysts were connected to the ovarian hilus. Two cortical inclusion cysts were observed in ten IO ovaries and one in ten BR ovaries. Low or no E-cadherin immuno-staining was seen in the OSE of all mice studied. Conversely, strong membrane immuno-staining was observed in rete ovarii epithelial cells. Variable E-cadherin immunoreactivity was seen in cells of hilar inclusion cysts, with strong staining observed in cuboidal ciliated cells and little or no staining in flat epithelial cells. Two of the three cortical cysts contained papillae, which showed E-cadherin immuno-staining at the edge of cells. However hilar and cortical cysts were not distinguishable by morphology, cell type or E-cadherin immunoreactivity. BrdU incorporation in cyst cells (1.4% [95% CI: 1.0 to 2.1]) was greater than in OSE (0.7% [95% CI: 0.4 to 1.2]) and very few BrdU-labeled cells were observed in rete ovarii at any age. Incessant ovulation significantly increased BrdU incorporation in OSE of older animals. CONCLUSION: These experiments confirm ovarian inclusion cysts develop with age in the CD-1 mouse strain, irrespective of total ovulation burden. We conclude longer periods of incessant ovulation do not lead to significant changes in inclusion cyst formation or steroidogenesis in CD-1 mice and inclusion cyst type can not be distinguished by morphology, cell proliferation rate or E-cadherin immunoreactivity

    A Rapid Decision Sampling Plan for Implementing Area—Wide Management of the Red Palm Weevil, Rhynchophorus ferrugineus, in Coconut Plantations of India

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    The red palm weevil Rhynchophorus ferrugineus Olivier (Curculionidae/Rhynchophoridae/Dryophthoridae) is a lethal pest of young coconut palms, Cocos nucifera L. (Arecales: Arecaceae), with a highly aggregated population distribution pattern. R. ferrugineus is managed in several coconut growing countries using area-wide pheromone based programmes that need a substantial commitment of funds over a period of time. Often, decisions to implement area-wide management of R. ferrugineus are based on pheromone trap captures in surveillance traps and or infestation reports. Implementing area-wide management of this pest on the basis of such data can be inaccurate, as it may either under or over estimate the pest intensity in the field. This study presents sampling plans for rapid and accurate classification of R. ferrugineus infestation in coconut plantations of India by inspecting palms to detect infestation in a sequence until a decision to either implement or not to initiate area-wide management of R. ferrugineus can be made. The sampling plans are based on a common aggregation index of 3.45, assumed action threshold values of either 1.0 (plan A) or 0.5 (plan B) per cent infested palms and a risk factor of making the wrong decision set at 0.05. Using plans A and B, if the cummulative number of infested palms in a young 1 hectare coconut plantation is zero out of 150 palms for both plans, then area-wide management is not required, while on the other hand, if the cummulative number of infested palms for the same area is 6 (plan A), or 5 (plan B), then area-wide management of R. ferrugineus is essential. The proposed sampling plans are efficient tools in decision making, particularly at very low and high levels of infestation and can also be used to assess the performance of R. ferrugineus IPM programmes that are in progress. These plans not only save time and money as only a small area needs to be sampled to arrive at a correct decision, but are also efficient in rating the infestation level accurately

    Lethal Influenza Virus Infection in Macaques Is Associated with Early Dysregulation of Inflammatory Related Genes

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    The enormous toll on human life during the 1918–1919 Spanish influenza pandemic is a constant reminder of the potential lethality of influenza viruses. With the declaration by the World Health Organization of a new H1N1 influenza virus pandemic, and with continued human cases of highly pathogenic H5N1 avian influenza virus infection, a better understanding of the host response to highly pathogenic influenza viruses is essential. To this end, we compared pathology and global gene expression profiles in bronchial tissue from macaques infected with either the reconstructed 1918 pandemic virus or the highly pathogenic avian H5N1 virus A/Vietnam/1203/04. Severe pathology was observed in respiratory tissues from 1918 virus-infected animals as early as 12 hours after infection, and pathology steadily increased at later time points. Although tissues from animals infected with A/Vietnam/1203/04 also showed clear signs of pathology early on, less pathology was observed at later time points, and there was evidence of tissue repair. Global transcriptional profiles revealed that specific groups of genes associated with inflammation and cell death were up-regulated in bronchial tissues from animals infected with the 1918 virus but down-regulated in animals infected with A/Vietnam/1203/04. Importantly, the 1918 virus up-regulated key components of the inflammasome, NLRP3 and IL-1β, whereas these genes were down-regulated by A/Vietnam/1203/04 early after infection. TUNEL assays revealed that both viruses elicited an apoptotic response in lungs and bronchi, although the response occurred earlier during 1918 virus infection. Our findings suggest that the severity of disease in 1918 virus-infected macaques is a consequence of the early up-regulation of cell death and inflammatory related genes, in which additive or synergistic effects likely dictate the severity of tissue damage

    A third generation vaccine for human visceral leishmaniasis and post kala azar dermal leishmaniasis : First-in-human trial of ChAd63-KH

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    BACKGROUND: Visceral leishmaniasis (VL or kala azar) is the most serious form of human leishmaniasis, responsible for over 20,000 deaths annually, and post kala azar dermal leishmaniasis (PKDL) is a stigmatizing skin condition that often occurs in patients after successful treatment for VL. Lack of effective or appropriately targeted cell mediated immunity, including CD8+ T cell responses, underlies the progression of VL and progression to PKDL, and can limit the therapeutic efficacy of anti-leishmanial drugs. Hence, in addition to the need for prophylactic vaccines against leishmaniasis, the development of therapeutic vaccines for use alone or in combined immuno-chemotherapy has been identified as an unmet clinical need. Here, we report the first clinical trial of a third-generation leishmaniasis vaccine, developed intentionally to induce Leishmania-specific CD8+ T cells. METHODS: We conducted a first-in-human dose escalation Phase I trial in 20 healthy volunteers to assess the safety, tolerability and immunogenicity of a prime-only adenoviral vaccine for human VL and PKDL. ChAd63-KH is a replication defective simian adenovirus expressing a novel synthetic gene (KH) encoding two Leishmania proteins KMP-11 and HASPB. Uniquely, the latter was engineered to reflect repeat domain polymorphisms and arrangements identified from clinical isolates. We monitored innate immune responses by whole blood RNA-Seq and antigen specific CD8+ T cell responses by IFNγ ELISPOT and intracellular flow cytometry. FINDINGS: ChAd63-KH was safe at intramuscular doses of 1x1010 and 7.5x1010 vp. Whole blood transcriptomic profiling indicated that ChAd63-KH induced innate immune responses characterized by an interferon signature and the presence of activated dendritic cells. Broad and quantitatively robust CD8+ T cell responses were induced by vaccination in 100% (20/20) of vaccinated subjects. CONCLUSION: The results of this study support the further development of ChAd63-KH as a novel third generation vaccine for VL and PKDL. TRIAL REGISTRATION: This clinical trial (LEISH1) was registered at EudraCT (2012-005596-14) and ISRCTN (07766359)

    Potential biological role of poly (ADP-ribose) polymerase (PARP) in male gametes

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    Maintaining the integrity of sperm DNA is vital to reproduction and male fertility. Sperm contain a number of molecules and pathways for the repair of base excision, base mismatches and DNA strand breaks. The presence of Poly (ADP-ribose) polymerase (PARP), a DNA repair enzyme, and its homologues has recently been shown in male germ cells, specifically during stage VII of spermatogenesis. High PARP expression has been reported in mature spermatozoa and in proven fertile men. Whenever there are strand breaks in sperm DNA due to oxidative stress, chromatin remodeling or cell death, PARP is activated. However, the cleavage of PARP by caspase-3 inactivates it and inhibits PARP's DNA-repairing abilities. Therefore, cleaved PARP (cPARP) may be considered a marker of apoptosis. The presence of higher levels of cPARP in sperm of infertile men adds a new proof for the correlation between apoptosis and male infertility. This review describes the possible biological significance of PARP in mammalian cells with the focus on male reproduction. The review elaborates on the role played by PARP during spermatogenesis, sperm maturation in ejaculated spermatozoa and the potential role of PARP as new marker of sperm damage. PARP could provide new strategies to preserve fertility in cancer patients subjected to genotoxic stresses and may be a key to better male reproductive health
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