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991.
Carmit Chalfon Valeria Martini Stefano Comazzi Luca Aresu Damiano Stefanello Fulvio Riondato Roberta Ferrari Laura Marconato 《Veterinary and comparative oncology》2019,17(2):139-146
Most dogs with large B‐cell lymphoma (LBCL) that undergo chemotherapy and achieve clinical complete remission (CR) eventually relapse. However, time to relapse (TTR) is unpredictable. The aims of this prospective study were to assess the influence of post‐chemotherapy lymph node (LN) infiltration by large CD21+ cells using flow cytometry (FC) on TTR, and to establish a cut‐off value of prognostic significance. Dogs with newly‐diagnosed, completely staged LBCL in CR after treatment were enrolled. Minimal residual disease (MRD) analysis by FC was performed on LN aspirates. TTR was calculated between MRD and relapse. Thirty‐one dogs were enrolled: 4% had stage V disease, and diffuse large B‐cell lymphoma was the most common histotype (74%). Based on LN infiltration at MRD evaluation, three groups were created: (a) acellular samples, (b) ≤0.5% infiltration and (c) >0.5% infiltration. Overall median TTR was 154 days (range, 31‐1974): 22 (71%) dogs relapsed during the study period, whereas 9 (29%) dogs did not. The difference among the three groups was significant (P = 0.042 log‐rank test): median TTR was not reached for dogs with LN infiltration ≤0.5% (range, 195‐429 days), 164 days (range 63‐1974) for dogs with acellular LN samples, and 118 days (range, 31‐232) for dogs with LN infiltration >0.5%. These results demonstrate that MRD assessment by FC on LN aspirates in dogs with LBCL in clinical CR predicts TTR. LN infiltration by >0.5% large CD21+ cells after treatment is an unfavourable prognostic factor. 相似文献
992.
Effects of tumour necrosis factor‐alpha and interleukin‐1 beta on in vitro development of bovine secondary follicles 下载免费PDF全文
Lais R. F. M. Paulino Ellen V. Cunha Anderson W. Barbalho Silva Glaucinete B. Souza Ewerton P. F. Lopes Mariana A. M. Donato Cristina A. Peixoto Bruno G. Matos‐Brito Robert van den Hurk José Roberto V. Silva 《Reproduction in domestic animals》2018,53(4):997-1005
The objective of this study was to determine the effects of TNF‐α and IL‐1β on development and survival of bovine secondary follicle culture in vitro for 18 days. Secondary follicles (~0.2 mm) were isolated from ovarian cortex and individually cultured at 38.5°C, with 5% CO2 in air, for 18 days, in TCM‐199+ alone (cultured control) or supplemented with 10 ng/ml IL‐1β, 10 ng/ml TNF‐α or both TNF‐α and IL‐1β. The effects of these treatments on growth, follicular survival, antrum formation, viability, ultrastructure and mRNA levels for GDF‐9, c‐MOS, H1foo and Cyclin B1 were evaluated. The results showed that addition of TNF‐α to culture medium increased follicular diameter and rate of antrum formation, whereas that of IL‐1β and a mixture of IL‐1β and TNF‐α did not do so. Ultrastructural analysis showed that, among the tested cytokine treatments, follicles cultured in the presence of TNF‐α had the best‐preserved oocytes and granulosa cells. The presence of TNF‐α, IL‐1β or both did not influence the expression of mRNAs analysed. In conclusion, in contrast to IL‐1β, TNF‐α promotes growth of and antrum formation in in vitro cultured bovine secondary follicles, while their ultrastructure and viability were maintained. 相似文献
993.
Tatiana H. Ferreira Leandro B.C. Teixeira Carrie A. Schroeder Cristina de Miguel Garcia Kristopher M. Schroeder 《Veterinary anaesthesia and analgesia》2018,45(6):811-819
Objectives
To describe an ultrasound-guided thoracic paravertebral block and determine the distribution after injection of two volumes of methylene blue in dog cadavers.Study design
Prospective experimental cadaveric study.Animals
Twelve dog cadavers weighing 11 ± 3 kg.Methods
Ultrasound-guided injections aimed at the fifth thoracic (T5) paravertebral space were performed in randomized order using 0.1 or 0.3 mL kg–1 dye solution (six dogs for each volume). Anatomic dissections determined dye spread characteristics, including the presence and degree of staining of spinal nerves, and the presence of intercostal and sympathetic trunk spread. Staining of mediastinum, epidural, intrapleural and contralateral thoracic paravertebral space was recorded.Results
There was no significant difference in dye distribution between groups. The use of anatomic landmarks resulted in the inaccurate identification of the T5 paravertebral space. The T4, T5 and T6 paravertebral spaces were injected in four, five and three of 12 dogs, respectively. Complete staining of the spinal nerve of the thoracic paravertebral space injected was observed in 11 of 12 dogs, and partial staining in one dog in the low-volume group. Multisegmental distribution was demonstrated with staining of contiguous spinal nerves in one dog in the high-volume group, and multiple segments of intercostal (three dogs) and sympathetic trunk (four dogs) spread in both groups. No mediastinal, epidural, intrapleural or contralateral thoracic paravertebral space staining was observed.Conclusions and clinical relevance
Ultrasound-guided injection at the thoracic paravertebral space resulted in staining of the spinal nerve in all dogs. However, T5 paravertebral space was not accurately identified using anatomic landmarks. Dye distribution was not significantly different between the two groups; therefore, the use of the lower-volume and multiple-site injections would be potentially necessary in clinical cases to achieve ipsilateral blockade of the thoracic wall. 相似文献994.
995.
996.
Ferrari M Brack A Romanelli MG Mettenleiter TC Corradi A Dal Mas N Losio MN Silini R Pinoni C Pratelli A 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2000,47(10):753-762
The capacity of a TK-negative (TK-) and gI/gE-negative (gI/gE-) pseudorabies virus (PRV) mutant to protect pigs against Aujeszky's disease carried out by experimental infection with a virulent PRV strain, was tested. There were three groups, each of four susceptible pigs which were inoculated twice by two different schedules. Group 1 received the modified virus by the intradermal (first inoculation)-intramuscular (second inoculation) routes; group 2 was treated by the intranasal (first inoculation)-intramuscular (second inoculation) routes. The third group was left untreated as the control. All of the pigs were challenged intranasally with a virulent PRV strain and they were subsequently injected with dexamethasone. Two pigs in each group were necropsied on days 5 and 15 after dexamethasone inoculation. The challenge exposure resulted in mild clinical signs, increase in growth and a shorter period of virus shedding in vaccinated pigs, whereas the control group showed severe signs of Aujeszky's disease. No difference in the titre of the virulent virus which was excreted by pigs of all three groups, was observed and all animals seroconverted. Both the mutant strain and the wild-type virus established a latent infection although only the latter was reactivated and shed. Slight lesions were observed in target tissues of the vaccinated animals and no significant differences were detected between the two inoculation schedules. 相似文献
997.
Rambozzi L Menzano A Mannelli A Romano S Isaia MC 《Journal of Feline Medicine and Surgery》2007,9(5):392-396
An epidemiological study was carried out to identify factors associated with the risk of cryptosporidian infection in cats. Faecal samples from 200 domestic cats were collected in the small animal clinic at the Faculty of Veterinary Medicine in Turin (north-west Italy). The faecal samples were analysed for the presence of Cryptosporidium species oocysts using a centrifugation concentration floatation method. For each cat, age, sex, breed, indoor/outdoor status, diet, diarrhoea and presence of other enteric parasites were analysed for association with Cryptosporidium species infection. Cryptosporidia oocysts were identified in 49 cats (24.5%) aged from 2 months to 18 years. Statistical analysis revealed that four variables are significantly associated with an increased risk of infection: less than 1 year of age (chi(2)=6.5, P=0.01), feeding home-cooked diet (chi(2)=6.92, P<0.01), presence of diarrhoea (chi(2)=4.34, P<0.037), and presence of other enteric parasites (chi(2)=10.31, P<0.01). No statistical differences were found for sex (chi(2)=1.56, P=0.21), breed (chi(2)=0.78, P=0.38) and outdoor/indoor status (chi(2)=1.49, P=0.22). Cryptosporidium species was the parasite most frequently detected in the cats surveyed. 相似文献
998.
Rodrigues CA Batista LF Teixeira MC Pereira AM Santos PO de Sá Oliveira GG de Freitas LA Veras PS 《Veterinary parasitology》2007,143(3-4):197-205
Leishmania chagasi is the causative agent of visceral leishmaniasis in both humans and dogs in the New World. The dog is the main domestic reservoir and its infection displays different clinical presentations, from asymptomatic to severe disease. Macrophages play an important role in the control of Leishmania infection. Although it is not an area of intense study, some data suggest a role for canine macrophages in parasite killing by a NO-dependent mechanism. It has been proposed that control of human disease could be possible with the development of an effective vaccine against canine visceral leishmaniasis. Development of a rapid in vitro test to predict animal responses to Leishmania infection or vaccination should be helpful. In this study, an in vitro model was established to test whether peripheral blood mononuclear cell (PBMC) supernatants from dogs immunized with promastigote lysates and infected with L. chagasi promastigotes could stimulate macrophages from healthy dogs in order to control parasite infection. PBMC from a majority of the immunized and experimentally infected dogs expressed IFN-gamma mRNA and secreted IFN-gamma when stimulated with soluble L. chagasi antigen (SLA) in vitro. Additionally, the supernatants from stimulated PBMC were able to reduce the percentage of infected donor macrophages. The results also indicate that parasite killing in this system is dependent on NO, since aminoguanidine (AMG) reversed this effect. This in vitro test appears to be useful for screening animal responses to parasite inoculation as well as studying the lymphocyte effector mechanisms involved in pathogen killing by canine macrophages. 相似文献
999.
1000.
Gabriella Tait Alberto Grassi Ferdinand Pfab Cristina M. Crava Daniel T. Dalton Roger Magarey Lino Ometto Silvia Vezzulli M. Valerio Rossi-Stacconi Angela Gottardello Andrea Pugliese Giuseppe Firrao Vaughn M. Walton Gianfranco Anfora 《Journal of pest science》2018,91(4):1213-1224
Drosophila suzukii (Diptera: Drosophilidae) is an invasive alien species devastating soft fruit crops in newly invaded territories. Little is known about the importance and potential of long-distance dispersal at a regional scale. The goal of this work is to investigate D. suzukii dispersal ability during different times of the season, and along an elevational gradient in a mountain valley in Trentino Province, Italy. We employed a mark–release–recapture strategy using protein markers. Flies were recaptured using fruit-baited traps. The protein-marked flies were positively identified using ELISA procedure. Additional microsatellite analyses were performed on D. suzukii collected during autumn at different elevations to characterize the population structure. Results suggest that a portion of the local D. suzukii population moves from low to high elevations during spring and summer and travels back to low elevations in autumn. Genetic analysis further revealed that samples collected during autumn at different elevations belong to the same population. These results show that D. suzukii are able to fly up to about 9000 m away from the marking point and that seasonal breezes likely facilitate long-distance movement. We suggest that these migrations have multiple functions for D. suzukii, including conferring the ability to exploit gradual changes of temperature, food, and ovipositional resources in spring and autumn, as well as to assist in the search for suitable overwintering sites in late autumn. Our findings help to unveil the complex ecology of D. suzukii in Italian mountainous regions and provide important clues for improving the efficacy of integrated pest management control techniques to combat this pest. 相似文献