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de Lima VM Peiro JR de Oliveira Vasconcelos R 《Veterinary immunology and immunopathology》2007,115(1-2):189-193
We investigated the production of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) during canine visceral leishmaniasis (VL) to gain a better understanding of the role of such multi-functional cytokines in parasite resistance. IL-6 and TNF-α levels were measured by capture ELISA in sera from 8 healthy dogs from a non-endemic area (control group) and in sera from 16 dogs from Araçatuba, SP, Brazil, an area endemic for leishmaniosis. The dogs from the endemic area were selected by positive ELISA serology against total Leishmania chagasi antigen, positive spleen imprints for Leishmania, and the presence of at least three clinical signs associated with active visceral leishmaniasis (fever, dermatitis, lymphoadenopathy, onychogryphosis, weight loss, cachexia, locomotory difficulty, conjunctivitis, epistaxis, hepatosplenomegaly, edema, and apathy).Enhanced systemic IL-6 production was found in sera from dogs with the active disease compared to healthy dogs (t-test, P < 0.05). In contrast, TNF-α did not differ between the two groups studied. There was no correlation between IL-6 production and anti-leishmanial antibody titers in the sera. Our findings suggest that IL-6 is a good marker of active disease during leishmaniasis, and that other cytokines may be involved in the hypergammaglobulinemia characteristic of canine visceral leishmaniasis. 相似文献
244.
Annalisa Liotta Valeria Busoni Maria Valentina Carrozzo Charlotte Sandersen Annick Gabriel Géraldine Bolen 《Veterinary radiology & ultrasound》2015,56(2):220-228
Epidural injections are commonly performed blindly in veterinary medicine. The aims of this study were to describe the lumbosacral ultrasonographic anatomy and to assess the feasibility of an ultrasound‐guided epidural injection technique in dogs. A cross sectional anatomic atlas of the lumbosacral region and ex vivo ultrasound images were obtained in two cadavers to describe the ultrasound anatomy and to identify the landmarks. Sixteen normal weight canine cadavers were used to establish two variations of the technique for direct ultrasound‐guided injection, using spinal needles or epidural catheters. The technique was finally performed in two normal weight cadavers, in two overweight cadavers and in five live dogs with radiographic abnormalities resulting of the lumbosacral spine. Contrast medium was injected and CT was used to assess the success of the injection. The anatomic landmarks to carry out the procedure were the seventh lumbar vertebra, the iliac wings, and the first sacral vertebra. The target for directing the needle was the trapezoid‐shaped echogenic zone between the contiguous articular facets of the lumbosacral vertebral canal visualized in a parasagittal plane. The spinal needle or epidural catheter was inserted in a 45° craniodorsal–caudoventral direction through the subcutaneous tissue and the interarcuate ligament until reaching the epidural space. CT examination confirmed the presence of contrast medium in the epidural space in 25/25 dogs, although a variable contamination of the subarachnoid space was also noted. Findings indicated that this ultrasound‐guided epidural injection technique is feasible for normal weight and overweight dogs, with and without radiographic abnormalities of the spine. 相似文献
245.
Genetic Variation and Population Structure in a Eurasian Collection of <Emphasis Type="Italic">Isatis tinctoria</Emphasis> L. 总被引:2,自引:0,他引:2
Giorgia Spataro Paola Taviani Valeria Negri 《Genetic Resources and Crop Evolution》2007,54(3):573-584
Isatis tinctoria L. is a biennial species which was cultivated in Europe until the 18th century to produce indigo, a pigment used for dyestuffs.
Today there is renewed interest in this ancient crop because of a market demand for natural dyes. Cultivation of the species
appears to be particularly suitable for marginal areas. Information about the evolutionary and genetic patterns of I. tinctoria is needed if varieties or to be developed in future breeding programs. The aim of this study was to assess the genetic variation
and similarity levels among and within natural populations of I. tinctoria from Europe and central Asia. Fifteen populations were used to carry out the genetic analyses with AFLP and SAMPL molecular
markers. Data collected were analysed by the UPGMA method and were used to perform AMOVA. The results are consistent with
the hypothesis that the crop originated in an eastern centre of origin and moved westward giving rise to a gene pool that
is quite different from the original. The wide within-population variation revealed by this study suggests that effective
breeding work to develop varieties suitable for marginal environments can be carried out easily. 相似文献
246.
Alessia Caso Fernanda Barbosa da Silva Germana Esposito Roberta Teta Gerardo Della Sala Laura P. A. Nunes Cavalcanti Alessandra Leda Valverde Roberto Carlos C. Martins Valeria Costantino 《Marine drugs》2021,19(12)
Porifera, commonly referred to as marine sponges, are acknowledged as major producers of marine natural products (MNPs). Sponges of the genus Phorbas have attracted much attention over the years. They are widespread in all continents, and several structurally unique compounds have been identified from this species. Terpenes, mainly sesterterpenoids, are the major secondary metabolites isolated from Phorbas species, even though several alkaloids and steroids have also been reported. Many of these compounds have presented interesting biological activities. Particularly, Phorbas sponges have been demonstrated to be a source of cytotoxic metabolites. In addition, MNPs exhibiting cytostatic, antimicrobial, and anti-inflammatory activities have been isolated and structurally characterized. This review provides an overview of almost 130 secondary metabolites from Phorbas sponges and their biological activities, and it covers the literature since the first study published in 1993 until November 2021, including approximately 60 records. The synthetic routes to the most interesting compounds are briefly outlined. 相似文献
247.
Under the name of lipophilic marine toxins, there are included more than 1000 toxic secondary metabolites, produced by phytoplankton, with the common chemical property of lipophilicity. Due to toxicological effects and geographical distribution, in European legislation relevant compounds are regulated, and their determination is accomplished with the reference liquid chromatography-tandem mass spectrometry method. In this study a modified ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method has been developed for the identification and quantification of EU-regulated lipophilic toxins. The method optimization included a refinement of SPE-C18 clean-up, in order to reduce matrix interferences. Improved LC conditions and upgraded chromatographic ammonia-based gradient ensured the best separation of all analytes and, in particular, of the two structural isomers (OA and DTX2). Also, different MS parameters were tested, and confirmation criteria finally established. The validation studies confirmed that all parameters were satisfactory. The requirements for precision (RSD% < 11.8% for each compound), trueness (recoveries from 73 to 101%) and sensitivity (limits of quantification in the range 3–8 µg kg−1) were fulfilled. The matrix effect, ranging from −9 to 19%, allowed the use of a calibration curve in solvent (3–320 µg kg−1 in matrix) for quantification of real samples. Method relative uncertainty ranged from 12 to 20.3%. Additionally, a total of 1000 shellfish samples was analysed, providing a first preliminary surveillance study that may contribute to the knowledge of lipophilic marine toxins contamination. Increase in algae proliferation events and intoxication cases, EFSA suggestions for modification of maximum permitted levels and toxicity equivalency factors, and new studies of important toxic effects underline that implementation of reference methods still represents an important task for health and food safety laboratories. 相似文献
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249.
Halil Özçelik Yiğit Taştan Ertugrul Terzi Adem Yavuz Sönmez 《Journal of fish diseases》2020,43(10):1325-1330
This study was designed to prevent fungal disease (Saprolegnia parasitica) that occurs on rainbow trout eggs (Oncorhynchus mykiss) by using wastes of onion (Allium cepa) and garlic (Allium sativum) plants. For this purpose, fertilized rainbow trout eggs were exposed to garlic skin, garlic stem and onion skin aqueous methanolic extracts by bathing in concentrations of 0.4, 0.8, 1.6 and 3.2 g/L, whereas the control group was left untreated. The larvae in all groups were monitored until they become free-swimming larvae, the number of eggs died due to fungus was recorded, and the data obtained from experimental groups and control group were compared. As a result, it was determined that onion skin had no effect on the number of eggs that died due to fungus (p > .05), while garlic skin and garlic stem extracts significantly reduced the number of fungal infestations without affecting the number of live larvae or the embryological development of the eggs (p < .05). In light of these data, we conclude that garlic skin (0.4, 0.8, and 1.6 g/L) and garlic stem (0.8 and 1.6 g/L) aqueous methanolic extracts are effective at preventing Saprolegnia parasitica infestation on rainbow trout eggs and may be used in aquaculture. 相似文献
250.
Isabel E. Gómez Villafañe Carla M. Bellomo Malena Rospide Paula Blanco Rocío Coelho Daniel O. Alonso Diana Arnica Julián Sanchez Loria Iara Figini Josefina Campos Valeria P. Martínez María Marcela Orozco 《Zoonoses and public health》2024,71(2):210-216
Hantavirus Pulmonary Syndrome (HPS) is an emerging infectious disease caused by orthohantaviruses in the Americas. In Argentina, since 1995, several reservoirs and virus variants have been described, but the northeastern and central endemic zones in the country include an area without human or rodent infections, despite sharing rodent species with areas with that disease. The aim of this study was to search for orthohantavirus in rodent communities that inhabit this area, which borders two endemic areas of HPS. Small rodents were captured in June of 2022 through a total effort of 644 trap nights distributed in five grids located in the Iberá National Park, Corrientes, Northeastern Argentina. All rodents were sexed, weighed, and the species was recorded. Blood samples were extracted to detect ANDV-specific immunoglobulin G (IgG), and to extract the RNA virus. Trimmed sequences were mapped against reference sequences from GenBank. We captured a total of 36 Oligoryzomys flavescens and 15 Oxymycterus rufus. We detected the O. flavescens species infected with Lechiguanas orthohantavirus in the camping area of the National Park. A nucleotide comparison with previously published sequences shows a 98.34% similarity to the virus obtained from a human case of HPS reported in the adjacent Misiones province. This study demonstrated, for the first time, that O. flavescens is a host of the Lechiguanas orthohantavirus in this zone and contributes to closing information gaps on the distribution of orthohantavirus in Argentina. Additionally, the high similarity with the hantavirus found in the human case of Misiones suggests that the reservoir in that province would also be O. flavescens (not previously confirmed). This information permits us to focus on the preventive measurements to protect the human population. 相似文献