Synthesis and phytotoxic activity of ozonides     

Barbosa LC  Pereira UA  Teixeira RR  Maltha CR  Fernandes SA  Forlani G 《Journal of agricultural and food chemistry》2008,56(20):9434-9440

The [4 + 3] cycloaddition of the proper furans with the oxyallyl cation, generated in situ from 2,4-dibromopentan-3-one, produced a series of 8-oxabicyclo [3.2.1]oct-6-en-3-ones. Exposure of the oxabicycles to ozone afforded the corresponding 8,9,10,11-tetraoxatricyclo[5.2.1.1 (2,6)]undecan-4-ones in variable yields (7-100%). The phytotoxic properties of these ozonides (or 1,2,4-trioxolanes) and their oxabicycle precursors were evaluated as the ability to interfere with the growth of Sorghum bicolor and Cucumis sativus seedlings. Among oxabicycles, the highest inhibitory activity was shown by compounds possessing a alpha,beta-unsaturated carbonyl moiety. A differential sensitivity of the two crops was evident with ozonides. The most active compounds were also tested against the weed species Ipomoea grandifolia and Brachiaria decumbens. To the best of our knowledge, this is the first article describing ozonides as potential herbicides.  相似文献   

An Approach to Air Pollution Source–Receptor Solution by Angular Distances     

Jorge F Magallanes  Leonardo Murruni  Darío Gomez  Patricia Smichowski  Raquel Gettar 《Water, air, and soil pollution》2008,188(1-4):235-245

This study presents the analysis of two series of concentrations of airborne particulate matter (APM) collected in two exploratory campaigns aimed at elucidating the source–receptor problem (SRP) in the metropolitan area of Buenos Aires. Although several techniques have been previously applied to interpret these measurements, we have almost exclusively used here the method of angular distances among objects (ADO) to discuss its advantages as a tool in understanding environmental questions within the source–receptor framework. We present a simple method of calculating the ADO, explain its chemical interpretation and the information that is possible to get by classifying the angular distances. A comparison among ADO with principal component analysis and Kohonen artificial neural networks is also discussed.  相似文献   

Triploid Induction in the Yellowtail Tetra,Astyanax altiparanae,Using Temperature Shock: Tools for Conservation and Aquaculture          下载免费PDF全文

Nadya Soares de Macedo Adamov  Nivaldo Ferreira do Nascimento  Elayna Cristina Silva Maciel  Matheus Pereira‐Santos  José Augusto Senhorini  Leonardo Luiz Calado  Mariana Machado Evangelista  Laura Satiko Okada Nakaghi  Alan Hertz Marín Guerrero  Takafumi Fujimoto  George Shigueki Yasui 《Journal of the World Aquaculture Society》2017,48(5):741-750

Triploidization is an interesting tool to produce sterile fish. In the yellowtail tetra, Astyanax altiparanae, this can be applied for aquaculture and surrogate technologies. In this study, we compared the efficacy of cold (2 C) or heat shock (38 C, 40 C, and 42 C) on triploid induction in the yellowtail tetra. The eggs were treated with cold or heat shock, 2 min postfertilization (30 min in cold shock or 2 min in heat shock). Intact embryos served as the control group. Ploidy status was confirmed by karyotyping, flow cytometry, and nuclear diameter of erythrocytes. The hatching rate decreased after cold shock (12.69 ± 15.76%) and heat shock at 42 C (0.35 ± 0.69%) in comparison with the control group (63.19 ± 16.82%). At 38 C and 40 C, hatching rates (61.29 ± 17.73% and 61.75 ± 22.1%, respectively) were not decreased. Only one triploid arose at 38 C (1/80). At 40 C, a high number of triploids arose (72/78). At 42 C, very few embryos developed into the hatching stage. A large number of haploid individuals arose after cold shock (61/75), with only one triploid. Our results indicate that heat shocking of embryos at 40 C is optimum for triploid production in the yellowtail tetra.  相似文献   

Identification of mycobacterial infections in wild boars in Northern Sardinia, Italy     

Zanetti S  Bua A  Molicotti P  Delogu G  Mura A  Ortu S  Sechi LA 《Acta veterinaria Hungarica》2008,56(2):145-152

During a six-month period a region of Northern Sardinia was monitored to check the presence of mycobacterial infections in wild boars. Forty-eight serum and 229 biopsy samples were collected from different animals and examined by both traditional diagnostic techniques (culture, bacterioscopic and molecular tests) and enzyme-linked immunosorbent assay (ELISA). The latter was used to determine the antibody response against both methylated and nonmethylated Heparin-Binding Haemagglutinin (HBHA) protein. Nine mycobacterial strains were isolated: three M. avium ssp. paratuberculosis (Map), three M. avium, one M. interjectum and two M. scrofulaceum strains. By PCR, only one animal was positive for M. bovis, whereas 10 animals were positive for Map. Out of the 48 sera tested, 19 showed a good humoral response to methylated HBHA and 17 to nonmethylated HBHA. Our data provide new information on the prevalence of mycobacterial infection among wild boars in Northern Sardinia and suggest that a more effective program should be developed to monitor mycobacterial infections in the wild animal population.  相似文献   

Establishment of three‐dimensional canine osteosarcoma cell lines showing vasculogenic mimicry and evaluation of biological properties after treatment with 17‐AAG     

Marcella Massimini  Raffaella De Maria  Daniela Malatesta  Mariarita Romanucci  Angela D'Anselmo  Leonardo Della Salda 《Veterinary and comparative oncology》2019,17(3):376-384

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Genetic association between different criteria to define sexual precocious heifers with growth,carcass, reproductive and feed efficiency indicator traits in Nellore cattle using genomic information     

Martin Bonamy  Sabrina Kluska  Elisa Peripolli  Marcos Vinícius Antunes de Lemos  Sabrina Thaise Amorim  Roberto Jose Vaca  Raysildo Barbosa Lbo  Letícia Mendes de Castro  Carina Ubirajara de Faria  Fabio Borba Ferrari  Fernando Baldi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(1):15-22

The aim of this study was to estimate genetic parameters for different precocious calving criteria and their relationship with reproductive, growth, carcass and feed efficiency in Nellore cattle using the single‐step genomic BLUP. The reproductive traits used were probability of precocious calving (PPC) at 24 (PPC24), 26 (PPC26), 28 (PPC28) and 30 (PPC30) months of age, stayability (STAY) and scrotal circumference at 455 days of age (SC455). Growth traits such as weights at 240 (W240) and 455 (W455) days of age and adult weight (AW) were used. Rib eye area (REA), subcutaneous fat thickness (SFT), rump fat thickness (RFT) and residual feed intake (RFI) were included in the analyses. The estimation of genetic parameters was performed using a bi‐trait threshold model including genomic information in a single‐step approach. Heritability for PPC traits was moderate to high (0.29–0.56) with highest estimates for PPC24 (0.56) and PPC26 (0.50). Genetic correlation estimates between PPC and STAY weakened as a function of calving age. Correlation with SC455, growth and carcass traits were low (0.25–0.31; ?0.22 to 0.04; ?0.09 to 0.18, respectively), the same occurs with RFI (?0.09 to 0.08), this suggests independence between female sexual precocity and feed efficiency traits. The results of this study encourage the use of PPC traits in Nellore cattle because the selection for such trait would not have a negative impact on reproductive, growth, carcass and feed efficiency indicator traits. Stayability for sexual precocious heifers (PPC24 and PPC26) must be redefined to avoid incorrectly phenotype assignment.  相似文献   

Application of recombinant antibody library for screening specific antigens in a bovine sperm cell subpopulation     

Sandro Gomes Soares  Jose Elpidio Barbosa   《Livestock Science》2008,114(2-3):188-193

Antibody phage display libraries are a useful tool in proteomic analyses. This study evaluated an antibody recombinant library for identification of sex-specific proteins on the sperm cell surface. The Griffin.1 library was used to produce phage antibodies capable of recognizing membrane proteins from Nelore sperm cells. After producing soluble monoclonal scFv, clones were screened on Simental sperm cells by flow cytometry and those that bound to 40–60% of cells were selected. These clones were re-analyzed using Nelore sperm cells and all clones bound to 40–60% of cells. Positive clones were submitted to a binding assay against male and female bovine leukocytes by flow cytometry and one clone preferentially bound to male cells. The results indicate that phage display antibodies are an alternative method for identification of molecules markers on sperm cells.  相似文献   

Comparison of serological assays for the diagnosis of canine visceral leishmaniasis in animals presenting different clinical manifestations   总被引：1，自引：0，他引：1  

Ferreira Ede C  de Lana M  Carneiro M  Reis AB  Paes DV  da Silva ES  Schallig H  Gontijo CM 《Veterinary parasitology》2007,146(3-4):235-241

Three serological methods, indirect fluorescent immunoassay (IFI), enzyme-linked immunosorbent assay (ELISA) and direct agglutination test (DAT) that are commonly employed in the diagnosis of canine visceral leishmaniasis (CVL), have been assessed. A total of 234 domestic dogs, drawn from an area in the municipality of Belo Horizonte, Minas Gerais, Brazil, endemic for visceral leishmaniasis, were submitted to clinical and parasitological examinations and serological assay. Sera collected from confirmed non-infected dogs (n=20), and from dogs with other parasitic diseases including Trypanosoma cruzi (n=7), Leishmania braziliensis (n=5), Toxoplasma gondii (n=5) and Ehrlichia canis (n=3), were also included in the study. IFI presented a lower sensitivity (72%) than ELISA (95%), although the specificities of these assays were low (52 and 64%, respectively) and both exhibited cross-reactivity with sera from dogs infected with T. cruzi, L. braziliensis and E. canis. In contrast, DAT exhibited a high sensitivity (93%) and a high specificity (95%) and cross-reacted with only one serum sample derived from an E. canis-infected dog. The reproducibilities of the ELISA and DAT assays were excellent, whilst that of IFI was considered to be acceptable. The results produced by ELISA and DAT were in complete agreement, those between ELISA and IFI were at an acceptable level of agreement, whilst the concurrence between the IFI and DAT results were either acceptable or poor depending on the clinical conditions of the group of dogs examined. Since there is no readily accessible method for the diagnosis of CVL that offers 100% specificity and sensitivity, the choice of technique employed must depend on the aim of the investigation.  相似文献   

Intraspecific breeding for reduced glucosinolate content in Ethiopian mustard (Brassica carinata A. Braun)     

Leonardo Velasco  José M. Fernández-martínez  Antonio De Haro 《Euphytica》1999,106(2):125-130

A total of six Ethiopian mustard ( Brassica carinata A. Braun) lines showing reduced levels of total glucosinolate content were developed through two different approaches. In the first case, eight lines with good agronomic performance under southern-Spanish conditions were first evaluated during two years for glucosinolate content, and a pedigree selection was then performed during three further generations. The line N2-142, with an average glucosinolate content of 82 μmoles g-1 seed, was developed from the original line C-49, with an average glucosinolate content of 115 μmoles g-1 seed. In the second case, chemical mutagenesis (EMS 1% v/v) was applied to seeds from the line C- 101, with an average glucosinolate content of 125 μmoles g- 1 seed. Five mutant lines showing an average glucosinolate content between 20 and 30 μmoles g-1 seed lower than the wild line C-101 were isolated in the M_3 or M_4 generation. The reduced glucosinolate content of these mutants was confirmed by developing and analysing the M_5 generation. Previous results in B. juncea suggest that a further reduction of total glucosinolate content might be achieved through genetic recombination between the different lines developed in this work. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Growth and feeding of Patagonian pejerrey Odontesthes hatcheri reared in net cages     

Juan Pablo Hualde  Walter Damián Ceferino Torres  Pablo Moreno  Mirna Ferrada  Mariela Ana Demicheli  Leonardo Javier Molinari  Carlos Marcelo Luquet 《Aquaculture Research》2011,42(6):754-763

An experiment was performed to evaluate the performance of Patagonian pejerrey during net cage rearing in the oligomesotrophic reservoir Exequiel Ramos Mexía. Survival, growth, nutrition and reproduction were evaluated for two lots of pejerrey, initial weights 4.0 and 2.5 g, reared in net cages for 22 and 14 months respectively. Fish were stocked at 29 and 48 individuals m^?3 densities and fed with an experimental pejerrey feed. During the experiment, temperature fluctuated between 6.6 and 19.6 °C. The two lots did not show substantial differences in survival (pooled survival at the end of the experiment >80%) and the thermal‐unit growth coefficient (TGC), daily feed intake and feeding efficiency were 0.43±0.19, 1.70±0.80 and 53.6±9.9 respectively. Digestive tract analysis showed that caged pejerrey can consume substantial quantities of natural food, taking advantage of its planktivorous condition. Pejerrey showed high percentage survival, slow growth and early sexual maturation in captivity. The use of the TGC is proposed as a model for describing the growth pattern of this species and other pejerrey under culture conditions.  相似文献