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Immunotherapy takes advantage of the immune system to prevent, control, and eliminate neoplastic cells. The research in the field has already led to major breakthroughs to treat cancer. In this work, we describe a platform that integrates in vitro bioassays to test the immune response and direct antitumor effects for the preclinical discovery of anticancer candidates. The platform relies on the use of dendritic cells that are professional antigen-presenting cells (APC) able to activate T cells and trigger a primary adaptive immune response. The experimental procedure is based on two phenotypic assays for the selection of chemical leads by both a panel of nine tumor cell lines and growth factor-dependent immature mouse dendritic cells (D1). The positive hits are then validated by a secondary test on human monocyte-derived dendritic cells (MoDCs). The aim of this approach is the selection of potential immunotherapeutic small molecules from natural extracts or chemical libraries.  相似文献   
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In the trapping ofTribolium castaneum (Herbst), the activity of traps baited or not baited with aggregation pheromone 4,8-dimethyldecanal is influenced by the presence in the traps of accumulate specimens trapped. This fact has been observed both in trap containing alive or dead specimens. Interactions in the different substances produced by adults of Red Flour Beetle during their communication relationship are involved in this behaviour.The results obtained in the trials suggests that the presence of alive insects in traps is attractive for other free specimens, but under conditions of overcrowding quinone produced by them regulate population density by counteracting the effect of the aggregation pheromone, causing the insects to disperse or suppressing aggregation behaviour.  相似文献   
4.
Porcine enteroviruses (PEVs) and teschoviruses (PTVs) are described as causative agents of neurological disorders, fertility disorders and dermal lesions of swine. Difficulties in the serological detection of these viruses may lead to a significant underestimation of infections with clinical symptoms. With the recent availability of genome sequence data for all the serotypes, molecular diagnosis is a possibility. The present study describes a new approach to molecular ‘serotyping’ of PTVs and PEV‐B viruses, involving the amplification and sequencing of a genomic fragment of the VP1 coding region. A molecular characterization of Italian entero‐teschovirus isolates was performed using a set of previously published and newly designed polymerase chain reaction primers. A total of 33 porcine isolates and 10 reference strains were analysed. Porcine enterovirus‐B samples were first diagnosed as positive for enterovirus by amplification of the 5′‐non‐translated region. Samples were then typed by amplification and sequencing of a portion of the VP1 coding region. Porcine enterovirus‐A and PTVs were detected by a published assay in the 5′‐NC region that allows them to be differentiated according to the size of amplification product, using the same set of primers. For serotype characterization of PTV, we evaluated four different regions: the N terminus of the capsid protein VP2, the region encoding for RNA‐dependent RNA polymerase, and the capsid VP1 and VP4 regions. The newly designed primers in the VP1 region was proved to be broad in range and suitable for serotype assessment and therefore constitute a useful diagnostic tool for molecular diagnosis of porcine teschovirus/enterovirus strains and for the study of molecular epidemiology and evolution of these viruses.  相似文献   
5.
In the trapping ofTribolium castaneum (Herbst), the activity of traps baited or not baited with aggregation pheromone 4,8-dimethyldecanal is influenced by the presence in the traps of accumulate specimens trapped. This fact has been observed both in trap containing alive or dead specimens. Interactions in the different substances produced by adults of Red Flour Beetle during their communication relationship are involved in this behaviour.The results obtained in the trials suggests that the presence of alive insects in traps is attractive for other free specimens, but under conditions of overcrowding quinone produced by them regulate population density by counteracting the effect of the aggregation pheromone, causing the insects to disperse or suppressing aggregation behaviour.The presence of dead insects in the traps, baited or not baited with pheromone, can be repellent for other free specimens ofT. castaneum, probably related to the presence of a residual alarm pheromone produced by the specimens before of death.With 10 figures and 3 tables  相似文献   
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The study evaluated the reproductive performance of primiparous sows submitted to post‐cervical insemination (PCAI) compared with cervical artificial insemination (CAI). Difficulty with catheter introduction, the occurrence of bleeding or semen backflow during insemination, and volume and sperm cell backflow up to 60 min after insemination were also evaluated. Sows were homogenously distributed, according to body weight loss in lactation, lactation length, weaned piglets, weaning‐to‐oestrus interval and total born in previous farrowing, in two treatments: PCAI (n = 165) with 1.5 × 109 sperm cells in 45 ml (2.4 ± 0.04 doses per sow) and CAI (n = 165) with 3 × 109 sperm cells in 90 ml (2.5 ± 0.04 doses per sow). During PCAI, sows were inseminated in the absence of boars. Transabdominal real‐time ultrasonography was performed at oestrus onset, immediately before the first insemination and at 24 h after last insemination. There was no difference (P > 0.05) between treatments in farrowing rate (91.5% × 89.1%) and litter size (12.5 × 11.9 piglets born, respectively for PCAI and CAI sows). Successful passage of the intrauterine catheter in all the inseminations was possible in 86.8% (165/190) of sows initially allocated to PCAI treatment. Difficulty of introducing the catheter in at least one insemination did not affect the reproductive performance of PCAI sows (P > 0.05). Bleeding during insemination did not affect (P > 0.05) the farrowing rate in both treatments, but litter size was reduced in CAI and PCAI sows (P ≤ 0.06). Percentage of spermatozoa present in backflow within 1 h after insemination was greater in CAI than PCAI sows (P < 0.01). More than 85% of primiparous sows can be successfully post‐cervical inseminated with doses containing 1.5 × 109 sperm cells in the absence of the boar during insemination without impairing the reproductive performance.  相似文献   
7.
Coevolution of mammals and their gut microbiota has profoundly affected their radiation into myriad habitats. We used shotgun sequencing of microbial community DNA and targeted sequencing of bacterial 16S ribosomal RNA genes to gain an understanding of how microbial communities adapt to extremes of diet. We sampled fecal DNA from 33 mammalian species and 18 humans who kept detailed diet records, and we found that the adaptation of the microbiota to diet is similar across different mammalian lineages. Functional repertoires of microbiome genes, such as those encoding carbohydrate-active enzymes and proteases, can be predicted from bacterial species assemblages. These results illustrate the value of characterizing vertebrate gut microbiomes to understand host evolutionary histories at a supraorganismal level.  相似文献   
8.
Supercritical fluid extraction (SFE) from aniseed using carbon dioxide was performed at 30 degrees C and pressures of 80-180 bar. The chemical composition of the SFE extract was determined by GC-MS; the quantitative analysis was done by GC-FID and TLC. The total amount of extractable substances or global yield (mass of extract/mass of feed) for the SFE process varied from 3.13 to 10.67% (mass). The solubilities of the anise essential oil in CO(2) were 0.0110, 0.0277, 0.0143, and 0.0182 kg of solute/kg of CO(2) at 80, 100, 140, and 180 bar, respectively. The major compounds identified and quantified in the extracts were anethole ( approximately 90%), gamma-himachalene (2-4%), p-anisaldehyde (<1%), methylchavicol (0.9-1.5%), cis-pseudoisoeugenyl 2-methylbutyrate ( approximately 3%), and trans-pseudoisoeugenyl 2-methylbutyrate ( approximately 1.3%). The Sovová model described quite well the experimental overall extraction curves.  相似文献   
9.
Winter cover crops are essential in conservation tillage systems to protect soils from erosion and for improving soil productivity. Black oat (Avena strigosa Schreb) and oilseed radish (Raphanus sativus L.) could be useful cover crops in the southeastern USA, but successful adoption requires understanding their influence on N availability in conservation tillage systems. Black oat and oilseed radish were compared to crimson clover (Trifolium incarnatum L.) and rye (Secale cereale L.) for biomass production and effects on N mineralization during the summer crop growing season from fall 1998 through summer 2002 near Watkinsville, GA. Rye produced 40 to 60% more biomass, although N contents were less than the other cover crops. Oilseed radish and black oat N contents were similar to crimson clover. Black oat, oilseed radish, and crimson clover C/N ratios were less than 30, whereas rye averaged 39. Amount of N mineralized in 90 days (N min90) measured with in situ soil cores was 1.3 to 2.2 times greater following black oat, crimson clover, and oilseed radish than following rye. No differences in N min90 were found between black oats, crimson clover, and oilseed radish in 1999 and 2000. The amount of potentially mineralizable N (N 0) was not different due to cover crop, but was 1.5 times greater in 2000 and 2002 than in 1999. The rate of N mineralization (k) was 20 to 50% slower following rye than the other three cover crops. Black oat and oilseed radish biomass production and soil N mineralization dynamics were more similar to crimson clover than to rye, which indicates that they could be used as cover crops in the southeast without significant changes in N recommendations for most crops.
Harry H. SchombergEmail:
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