1,720,966 research outputs found
Failure in dry period vaccination strategy for bovine viral diarrhea virus
No full textBovine viral diarrhea is a common disease of cattle and has significant impact on animal welfare worldwide. There are fundamental approaches i.e. elimination of persistently infected animals, vaccination and biosecurity measures for effective control and eradication of BVD virus (BVDV). By this study, the presence of persistent infection with divergent BVDV subgenotype in the calves in a dairy herd having regular vaccination program was investigated. In the herd, vaccinated with a killed whole virion trivalent vaccine (composed of BVDV-1a) during the dry period of the cows, abortion cases were existed in the late autumn 2019. During herd screening by BVDV antigen-ELISA, 2 out of 300 dams were detected positive. Following, by ear notch-based BVDV antigen-ELISA, 30 calves were detected positive. Confirmation of persistent BVDV infection was performed 3 weeks later by testing with antigen-ELISA, where 8 of 9 selected newborn calves were positive for the second time. The entire antigen-ELISA positive samples were subjected to virus isolation on MDBK cell culture and identified as non-cytopathogenic pestiviruses by indirect immunoperoxidase assay. Presence of pestivirus RNA was detected in the 8 isolates by panpestivirus RT-PCR. Analysis of the 5'UTR regions revealed that BVDV-1 r circulate in the herd. Results of this study lead to questioning the efficiency of dry period vaccination strategy against BVDV. But otherwise, vaccination with BVDV-1a can be inefficient for complete protection against BVDV-1 r. Therefore, serological relationship between mentioned subgenotypes or protection by current vaccines against latest field isolates needs to be investigated before development of new BVDV vaccine candidates
Determination of inactivation kinetics in vaccine candidate local BVD virus strains and immunization studies in experimental animals
No full textBovine viral diarrhea virus (BVDV) ülkemizde ve dünyada yaygın olarak görülmekle birlikte hastalığa karşı koruma ve kontrol stratejileri geliştirilmektedir. Koruma kontrol programlarında ön plana çıkan önlemlerden biri de aşılama olarak görülmektedir. Tez çalışmasında aşı adayı yerel BVDV suşlarının çoğalma karakterizasyonlarının, inaktivasyon kinetiğinin ve farklı adjuvantlarla hazırlanan inaktif BVDV aşı formülasyonlarının deney hayvanlarındaki serolojik yanıtlarının belirlenmesi amaçlandı. BVDV TR-21, TR-26 ve TR-15 suşlarının optimum MOI değerleri sırasıyla 1, 0,1 ve 0,1 MOI olarak tespit edildi. Ayrıca TR-21, TR-26 ve TR-15 suşlarının çoğalma eğrileri oluşturularak virus ekimini takiben en yüksektitrelere sırasıyla 48., 12., ve 36. saatlerde ulaştığı saptandı. Kimyasal olarak BEI maddesi kullanılarak yapılan inaktivasyon kinetiği çalışmasında TR-21, TR-26 ve TR-15 suşları sırasıyla 16., 10., ve 10. saatte tamamen inaktive olduğu tespit edilmiştir. Yağ bazlı, AlOH3 bazlı ve saponin adjuvantları kullanılarak oluşturulan formülasyonlarla kobay ve farelere immunizasyon işlemi gerçekleştirildi. Aşı sonrası gelişen humoral immun yanıtı belirlemek için in-house ELISA ve nötralizasyon testi uygulanarak verilerin birbirini teyit ettiği gösterildi. AlOH3 bazlı adjuvant gruplarına nazaran yağ bazlı adjuvant gruplarının aşıda etkili şekilde çalıştığı belirlendi. Yağ bazlı adjuvant gruplarında F-3 formülasyonunun 21. ve 51. günlerdeki antikor titreleri yüksek olsa da 81. ve 111. günlerde F-4 grubunun aşağısında kaldığı tespit edilmiştir. Aynı zamanda F-4 grubunda kullanılan adjuvantın yapısı gereği (w/o/w) aşı formülasyonu aşamasında kullanımının daha rahat olması açısından kolaylık sağlayacağı düşünülmektedir. Aşılarda bulunan yerel suşların önemiyle beraber homolog ve heterolog suşlara karşı etkinlikleri ortaya koyulmuştur. İleriki süreçlerde inaktif yerel aşı üretimi için uygulanabilir güncel veriler elde edilmiştir.Although bovine viral diarrhea virus (BVDV) is common in our country and in the world, protection and control strategies are being developed against the disease. One of the prominent measures in protection control programs is seen as vaccination. In the thesis study, it was aimed to determine the proliferation characteristics, inactivation kinetics of vaccine candidate local BVDV strains and the serological responses of inactive BVDV vaccine formulations prepared with differentadjuvants in experimental animals. Optimum MOI values of BVDV TR-21, TR-26 and TR-15 strains were determined as 1, 0,1 and 0,1, respectively. In addition,growth curves of TR-21, TR-26 and TR-15 strains were created and it was determined that they reached the highest titers at 48, 12, and 36 hours, respectively, after virus cultivation. In the inactivation kinetic study using BEI as a chemical, itwas determined that the TR-21, TR-26 and TR-15 strains were completely inactivated at the 16th, 10th and 10th hours, respectively. Guinea pigs and mice were immunized with formulations using oil-based (ISA 50 and 206), AlOH3-based and saponin adjuvants. In-house ELISA and neutralization test were applied to determine the humoral immune response developed after vaccination, and it was shown that the data confirmed each other. It was determined that oil-based adjuvant groups worked effectively in the vaccine compared to AlOH3-based adjuvant groups. Although the antibody titers of the F-3 formulation on the 21st and 51st days were high in the oil-based adjuvant groups, it was found to be below the F-4 group on the 81st and 111th days. At the same time, due to the nature of the adjuvant used in the F-4 group (w/o/w), it is thought that it will provide convenience in terms of being more comfortable to use in the vaccine formulation stage. The importance of local strains in vaccines and their effectiveness against homologous and heterologousstrains have been demonstrated. Applicable up-to-date data were obtained for the production of inactivated local vaccines in the future
Determination of inactivation kinetics in vaccine candidate local BVD virus strains and immunization studies in experimental animals
No full textBovine viral diarrhea virus (BVDV) ülkemizde ve dünyada yaygın olarak görülmekle birlikte hastalığa karşı koruma ve kontrol stratejileri geliştirilmektedir. Koruma kontrol programlarında ön plana çıkan önlemlerden biri de aşılama olarak görülmektedir. Tez çalışmasında aşı adayı yerel BVDV suşlarının çoğalma karakterizasyonlarının, inaktivasyon kinetiğinin ve farklı adjuvantlarla hazırlanan inaktif BVDV aşı formülasyonlarının deney hayvanlarındaki serolojik yanıtlarının belirlenmesi amaçlandı. BVDV TR-21, TR-26 ve TR-15 suşlarının optimum MOI değerleri sırasıyla 1, 0,1 ve 0,1 MOI olarak tespit edildi. Ayrıca TR-21, TR-26 ve TR-15 suşlarının çoğalma eğrileri oluşturularak virus ekimini takiben en yüksektitrelere sırasıyla 48., 12., ve 36. saatlerde ulaştığı saptandı. Kimyasal olarak BEI maddesi kullanılarak yapılan inaktivasyon kinetiği çalışmasında TR-21, TR-26 ve TR-15 suşları sırasıyla 16., 10., ve 10. saatte tamamen inaktive olduğu tespit edilmiştir. Yağ bazlı, AlOH3 bazlı ve saponin adjuvantları kullanılarak oluşturulan formülasyonlarla kobay ve farelere immunizasyon işlemi gerçekleştirildi. Aşı sonrası gelişen humoral immun yanıtı belirlemek için in-house ELISA ve nötralizasyon testi uygulanarak verilerin birbirini teyit ettiği gösterildi. AlOH3 bazlı adjuvant gruplarına nazaran yağ bazlı adjuvant gruplarının aşıda etkili şekilde çalıştığı belirlendi. Yağ bazlı adjuvant gruplarında F-3 formülasyonunun 21. ve 51. günlerdeki antikor titreleri yüksek olsa da 81. ve 111. günlerde F-4 grubunun aşağısında kaldığı tespit edilmiştir. Aynı zamanda F-4 grubunda kullanılan adjuvantın yapısı gereği (w/o/w) aşı formülasyonu aşamasında kullanımının daha rahat olması açısından kolaylık sağlayacağı düşünülmektedir. Aşılarda bulunan yerel suşların önemiyle beraber homolog ve heterolog suşlara karşı etkinlikleri ortaya koyulmuştur. İleriki süreçlerde inaktif yerel aşı üretimi için uygulanabilir güncel veriler elde edilmiştir.Although bovine viral diarrhea virus (BVDV) is common in our country and in the world, protection and control strategies are being developed against the disease. One of the prominent measures in protection control programs is seen as vaccination. In the thesis study, it was aimed to determine the proliferation characteristics, inactivation kinetics of vaccine candidate local BVDV strains and the serological responses of inactive BVDV vaccine formulations prepared with differentadjuvants in experimental animals. Optimum MOI values of BVDV TR-21, TR-26 and TR-15 strains were determined as 1, 0,1 and 0,1, respectively. In addition,growth curves of TR-21, TR-26 and TR-15 strains were created and it was determined that they reached the highest titers at 48, 12, and 36 hours, respectively, after virus cultivation. In the inactivation kinetic study using BEI as a chemical, itwas determined that the TR-21, TR-26 and TR-15 strains were completely inactivated at the 16th, 10th and 10th hours, respectively. Guinea pigs and mice were immunized with formulations using oil-based (ISA 50 and 206), AlOH3-based and saponin adjuvants. In-house ELISA and neutralization test were applied to determine the humoral immune response developed after vaccination, and it was shown that the data confirmed each other. It was determined that oil-based adjuvant groups worked effectively in the vaccine compared to AlOH3-based adjuvant groups. Although the antibody titers of the F-3 formulation on the 21st and 51st days were high in the oil-based adjuvant groups, it was found to be below the F-4 group on the 81st and 111th days. At the same time, due to the nature of the adjuvant used in the F-4 group (w/o/w), it is thought that it will provide convenience in terms of being more comfortable to use in the vaccine formulation stage. The importance of local strains in vaccines and their effectiveness against homologous and heterologousstrains have been demonstrated. Applicable up-to-date data were obtained for the production of inactivated local vaccines in the future
Pathogenicity assessment of a bovine viral diarrhea virus type 1l (bvdv-1l) strain in experimentally infected calves
No full textBovine viral diarrhea is a widespread and economically important viral disease for livestock which can cause clinically diverse manifestations. The number of established BVDV subgenotypes has increased, not only the serological relationships of recently described subgenotypes but virulence and pathogenic characteristics have not yet been mostly elaborated. The dominant BVDV subgenotype in Turkiye was elaborated to be BVDV-1l, that involves more than half of field strains and there is no scientific data to identify the pathogenicity of this strain so far. This study investigated the pathogenicity of a selected field strain (TR-72) from subgenotype BVDV-1l. Experimental infection was implemented by intranasal inoculation of the strain TR-72 (10 x105.5) to four young calves which were previously not vaccinated and were free both for BVDV antibodies and antigens. Clinical changes as well as blood parameters, body temperature, and viremia were monitored for 14 days. Only mild clinical signs associated with respiratory signs of BVDV infection were observed. Detected clinical signs included nasal discharge, conjunctivitis, cough, fatigue, high rectal temperature reaching 40.7 celcius, and white blood cell counts depression started from the 2nd day and 40.4% decreased between the 12th and 14th days post-infection (poi). The presence of viremia was investigated by virus isolation, RT-PCR, and real-time RT-PCR from blood samples. The efficiency of experimental infection was established not only by observed clinical signs but also by virus isolation from blood leukocytes between the 5th and 8th days poi., virus detection was obtained by realtime PCR between the 3rd - 13th days poi. Besides, the recorded mild clinical signs, high fever, long duration of viremia , and high decrease in blood parameters obtained in this study, it was shown that the noncytopathogenic BVDV-1l strain TR-72 has a moderate virulence in naive cattle
Optimum processing conditions for a trivalent-inactivated bovine viral diarrhea virus (BVDV) vaccine using field strains and immunogenicity of candidate formulations with different adjuvants
No full textBovine viral diarrhea virus (BVDV) is among the common bovine pathogens worldwide. One of the prominent protection measures of BVDV is vaccination. This study aimed to determine the growth characteristics, inactivation kinetics of vaccine candidates using local BVDV strains [TR-26 (BVDV-1f), TR-21 (BVDV-1l), and TR-15 (BVDV-2b)], and the serological response in experimental animals to inactivated BVDV vaccine formulations prepared with different adjuvants. Optimum MOI values for BVDV strains TR-26, TR-21, and TR-15 were determined as 0.1, 1.0, and 0.01, respectively. In addition, growth curves of TR-26, TR-21, and TR-15 strains were created, and it was determined that they reached the highest titers at 12, 48, and 36 h p.i., respectively. The strains TR-26, TR-21, and TR-15 with titers of 106.5, 106.5, and 105.25 TCID50/ml were completely inactivated by 1 mM binary ethyleneimine (BEI) at the 10th, 16th, and 10th hours of treatment, respectively. Guinea pigs were immunized with four vaccine formulations (F1, F2, F3, F4), two with aluminum-based [Al(OH)3, Al(OH)3+Saponin] and two with oil-based (ISA 50 and ISA 206) adjuvants. Neutralization tests were applied to determine the humoral immune response developed after vaccination. Both homologous and heterologous BVDV strains were used for evaluations. Oil adjuvanted vaccines were more efficient to induce antibody titers compared to Al(OH)3-based vaccines. In addition, between the oil adjuvanted vaccines, the titers of neutralizing antibodies obtained by Montanide® ISA 206 formulation were significantly higher than in Montanide® ISA 50 (p < 0.05). Post-vaccinal neutralizing antibodies were detected in the first sampling at 21st day and lasted longer than a 111 days period. The highest antibody response in Guinea pigs was for the strain TR-15. The availability of using BVDV-lf, 1l, and 2b local strains in vaccines and their effectiveness against homologous and heterologous strains have been demonstrated.Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) 119 O 57
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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