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1.
Poult Sci ; 102(3): 102412, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36621101

RESUMO

Phenotypes on individual animals are required for breeding programs to be able to select for traits. However, phenotyping individual animals can be difficult and time-consuming, especially for traits related to health, welfare, and performance. Individual broiler behavior could serve as a proxy for these traits when recorded automatically and reliably on many animals. Sensors could record individual broiler behavior, yet different sensors can differ in their assessment. In this study a comparison was made between a passive radio frequency identification (RFID) system (grid of antennas underneath the pen) and video tracking for the determination of location and movement of 3 color-marked broilers at d 18. Furthermore, a systems comparison of derived behavioral metrics such as space usage, locomotion activity and apparent feeding and drinking behavior was made. Color-marked broilers simplified the computer vision task for YOLOv5 to detect, track, and identify the animals. Animal locations derived from the RFID-system and based on video were largely in agreement. Most location differences (77.5%) were within the mean radius of the antennas' enclosing circle (≤128 px, 28.15 cm), and 95.3% of the differences were within a one antenna difference (≤256 px, 56.30 cm). Animal movement was not always registered by the RFID-system whereas video was sensitive to detection noise and the animal's behavior (e.g., pecking). The method used to determine location and the systems' sensitivities to movement led to differences in behavioral metrics. Behavioral metrics derived from video are likely more accurate than RFID-system derived behavioral metrics. However, at present, only the RFID-system can provide individual identification for non-color marked broilers. A combination of verifiable and detailed video with the unique identification of RFID could make it possible to identify, describe, and quantify a wide range of individual broiler behaviors.


Assuntos
Dispositivo de Identificação por Radiofrequência , Animais , Dispositivo de Identificação por Radiofrequência/métodos , Galinhas , Comportamento de Ingestão de Líquido , Locomoção
2.
Pol J Vet Sci ; 25(2): 231-235, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35861962

RESUMO

The aims of this study were to evaluate the prevalence of Coxiella burnetii on both herd and animal level based on ELISA and PCR tests. Antibodies to C. burnetii were detected in 22 out of the 24 bulk tank milk samples (91.6%) tested by ELISA and the IS1111 element of C. burnetii was detected in 10 out of the 24 samples (41.6%) by real-time polymerase chain reaction (PCR). ELISA testing showed individual seropositivity in 67 out of the 165 cows (40.6%) examined in 24 dairy cattle farms in different parts of the Czech Republic. Our study revealed that the prevalence of C. burnetii has increased substantially in the Czech Republic over the past 30 years, and that the causative agent is a potential risk factor for some reproductive problems in dairy farms and a possible risk factor for human infection.


Assuntos
Doenças dos Bovinos , Coxiella burnetii , Febre Q , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Coxiella burnetii/genética , República Tcheca/epidemiologia , Fazendas , Feminino , Humanos , Leite , Prevalência , Febre Q/epidemiologia , Febre Q/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária
3.
Prev Vet Med ; 183: 105124, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32889487

RESUMO

Paratuberculosis is a chronic incurable disease caused by Mycobacterium avium subsp. paratuberculosis (MAP), which leads to extensive economic losses on dairy farms, and may also pose serious public health risk to the consumers. The aim of our study was to estimate the true prevalence of paratuberculosis in commercial dairy cattle herds participating in a voluntary MAP testing programme that started in February 2018 in Hungary. Milk samples collected during official milk recording were used for MAP ELISA testing. A Bayesian two-stage hierarchical (herd and animal level) model was fitted to the data. Altogether, 26,437 cows from 51 herds were sampled, which represents 14.4 % of the Hungarian dairy cow population. The median herd size was 477 cows (interquartile range: 331-709). Each studied farm had at least one ELISA positive cow, resulting in a herd-level apparent prevalence of 100 %. The overall within herd apparent prevalence was 5.5 %. Herd-level true prevalence was estimated at 89.1 % [95 % credible interval (CrI): 80.3-95.6%]. Within the infected herds, the median animal-level true prevalence was 4.4 % (3.2-5.8%) for primiparous and 10.3 % (7.9-12.9%) for multiparous cows, respectively. The probability of having an animal-level true prevalence of at least 5% among primiparous cows, within infected herds, was 17.8 %. Similarly, the probability of having an animal-level true prevalence of at least 5% or 10 % among multiparous cows was 100 % and 56 %, respectively. Simulations assuming herd-level true prevalence varying from 50 to 100 % revealed high accuracy of our Bayesian model. Our study showed that a large percentage of the studied Hungarian dairy cattle herds was infected with MAP.


Assuntos
Doenças dos Bovinos/epidemiologia , Leite/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/epidemiologia , Animais , Teorema de Bayes , Bovinos , Indústria de Laticínios , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Hungria/epidemiologia , Prevalência , Probabilidade
4.
Animal ; 12(11): 2401-2406, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29433595

RESUMO

As a result of the increase in herd size and the intensification of production, the complexity of reproductive management has been growing in dairy herds. The aim of our study was to examine the associations of management practices and reproductive performance in Holstein cows on large commercial dairy farms. Management practices applied to cows were surveyed between 22 May and 6 November 2015 in 34 large Holstein-Friesian dairy herds in Hungary. Individual data of 23 784 cows that calved between 1 January 2014 and 31 December 2014 in the surveyed herds were gathered. Associations between the management practices and the reproductive parameters were analyzed by mixed effects models. Regarding heat abatement we found that ventilation with sprinklers was associated with the shortest breeding interval (P0.05) results to lack of heat stress protection. It was also revealed, that lack of a well-established voluntary waiting period (VWP) or a VWP shorter than 50 days was associated with less days to first service (P<0.01), shorter breeding interval (P<0.01) and calving to conception interval (P<0.05), as well as higher odds of carrying a calf by 200 days in milk (P<0.01) compared with those using a VWP of at least 50 days. Those farms that applied transrectal ultrasonography were more likely to use ventilation with sprinklers (P<0.05), hormonal synchronization (P<0.01) and to perform early pregnancy diagnosis followed by pregnancy recheck (P<0.05). The application of transrectal ultrasonography with one of the aforementioned practices was associated with reduced days to first service (P<0.05), shorter breeding interval (P<0.05) and higher odds of pregnancy at 200 days in milk (P<0.05). Our study highlights the management practices most closely related to improved reproductive performance, which are, therefore, suggested to be applied on dairy farms, considering the local circumstances of the individual farms.


Assuntos
Bovinos/fisiologia , Resposta ao Choque Térmico , Leite/metabolismo , Reprodução , Animais , Cruzamento , Indústria de Laticínios , Fazendas , Feminino , Temperatura Alta , Lactação , Gravidez
5.
Anim Reprod Sci ; 188: 114-122, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29175177

RESUMO

The aim of this study was to assess the relationship between the reproductive management practices and the performance of replacement heifers on large commercial dairy farms. The individual data of 14,763 heifers, first inseminated in 2014, were analysed from 33 Holstein-Friesian dairy herds in Hungary. The relationships between management practices and major reproductive parameters (age at first service, AFS; age at first calving, AFC; conception risk to first insemination, CR1; and pregnancy status at 20 months of age) were examined by mixed-effects models, with the herd as the random effect. The results showed that farms using oestrus detection aids experienced reduced AFS (p<0.001) and AFC (p=0.001). Observation of oestrus for shorter periods instead of continuously showed a tendency towards lower AFC (p=0.057) and was associated with higher odds of pregnancy at 20 months of age (p=0.020). Heifers on farms using sexed semen had younger AFS, but poorer CR1, compared to those using conventional semen exclusively (p<0.05). In addition, the odds of heifers being pregnant by 20 months of age was higher on farms with more experience using sexed semen (p=0.020). Frequent pregnancy diagnosis (i.e. more than once per week) was associated with younger AFC (p=0.023). Our results suggest the use of certain advanced reproductive management practices for heifer reproductive management in large dairy herds (e.g. oestrus detection aids), which can improve reproductive efficiency considerably, but are currently used only to a limited extent.


Assuntos
Criação de Animais Domésticos , Prenhez , Reprodução/fisiologia , Envelhecimento , Animais , Bovinos , Feminino , Inseminação Artificial/veterinária , Gravidez , Prenhez/fisiologia
6.
Gene Ther ; 16(10): 1223-33, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19587709

RESUMO

Survival after pancreatic cancer remains poor despite incremental advances in surgical and adjuvant therapy, and new strategies for treatment are needed. Oncolytic virotherapy is an attractive approach for cancer treatment. In this study, we have evaluated the effectiveness of the Lister vaccine strain of vaccinia virus armed with the endostatin-angiostatin fusion gene (VVhEA) as a novel therapeutic approach for pancreatic cancer. The Lister vaccine strain of vaccinia virus was effective against all human pancreatic carcinoma cells tested in vitro, especially those insensitive to oncolytic adenovirus. The virus displayed inherently high selectivity for cancer cells, sparing normal cells both in vitro and in vivo, with effective infection of tumors after both intravenous (i.v.) and intratumoral (i.t.) administrations. The expression of the endostatin-angiostatin fusion protein was confirmed in a pancreatic cancer model both in vitro and in vivo, with evidence of inhibition of angiogenesis. This novel vaccinia virus showed significant antitumor potency in vivo against the Suit-2 model by i.t. administration. This study suggests that the novel Lister strain of vaccinia virus armed with the endostatin-angiostatin fusion gene is a potential therapeutic agent for pancreatic cancer.


Assuntos
Terapia Genética/métodos , Terapia Viral Oncolítica/métodos , Neoplasias Pancreáticas/terapia , Vaccinia virus/genética , Angiostatinas/genética , Animais , Fusão Gênica Artificial , Terapia Combinada , Endostatinas/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/patologia , Proteínas Recombinantes de Fusão , Células Tumorais Cultivadas , Vaccinia virus/fisiologia , Replicação Viral , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Gene Ther ; 14(1): 20-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16915291

RESUMO

Vaccinia virus has been shown to efficiently infect tumor cells. Therefore, vaccinia virus represents a potentially safe and effective antitumor agent against ovarian cancer. Here, we assessed the ability of vaccinia virus to preferentially infect and control both human and murine ovarian tumors in vivo. We used the non-invasive luminescence imaging system to monitor the infection and suppression of ovarian tumors by vaccinia in live mice. Our data indicated that vaccinia was able to effectively infect and kill both human and murine ovarian tumors. Vaccinia virus administered to mice intraperitoneally was specifically targeted to the murine or human ovarian tumors and led to antitumor responses. These findings suggest that vaccinia virus is capable of selectively targeting and controlling ovarian tumors. Thus, intraperitoneal injection with vaccinia virus may provide a potentially effective strategy for treating advanced-stage ovarian cancers.


Assuntos
Terapia Genética/métodos , Terapia Viral Oncolítica/métodos , Neoplasias Ovarianas/terapia , Vaccinia virus/genética , Vacínia/transmissão , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Luciferases/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Transplante de Neoplasias , Neoplasias Ovarianas/virologia , Transfecção/métodos
8.
Cytokine ; 15(6): 305-14, 2001 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-11594797

RESUMO

Single intratumoural treatment of nude mice with a vaccinia virus (VV)-expressing interleukin-1 (IL-2) or IL-12 induced significant tumour growth inhibition associated with clear signs of toxicity. At a low virus dose, only some treated animals showed signs of toxicity. We characterized and compared the activity of NK and B cells and major pro-inflammatory factors (IFN-gamma, TNF-alpha) in treated animals with and without toxicity. One week after treatment animals exhibiting signs of cytokine-related toxicity showed dramatic increases in several measured parameters. High leukocyte and lymphocyte counts in blood and marked increases in NK and CD25(+)cells in both blood and spleen were associated with IL-2-induced toxicity, while IL-12-induced toxicity was related to a great elevation of CD25(+)cells in blood and CD71(+)cells in the spleen. In contrast, immune activation in animals free of toxicity was observed on day 2 after the treatment, which drastically declined by day 7. Thus, immune responses induced by IL-2 and IL-12 therapy appear to play important roles in both tumour inhibition and the accompanying toxicity. Short-term effects induced by IL-2 and IL-12 could be critical for antitumour therapy that prolongs survival and protects from adverse side effects.


Assuntos
Citocinas/toxicidade , Terapia Genética/métodos , Interleucina-12/genética , Interleucina-2/genética , Neoplasias/terapia , Vaccinia virus/genética , Animais , Antígenos CD/biossíntese , Antígenos de Diferenciação de Linfócitos B/biossíntese , Linfócitos B/metabolismo , Linhagem Celular , Células Cultivadas , Citocinas/genética , Fibroblastos/metabolismo , Citometria de Fluxo , Glioma/terapia , Interferon gama/metabolismo , Células Matadoras Naturais/metabolismo , Leucócitos/metabolismo , Linfócitos/metabolismo , Camundongos , Camundongos Nus , Transplante de Neoplasias , Tamanho do Órgão , Ratos , Receptores de Interleucina-2/biossíntese , Receptores da Transferrina , Baço/metabolismo , Fatores de Tempo , Transgenes , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/metabolismo
9.
J Gene Med ; 3(5): 468-77, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11601760

RESUMO

BACKGROUND: Mild psoralen and UV (PUV) treatments inactivate viral DNA replication, but the virus retains its ability to infect cells. Thus, PUV treatment of vaccinia virus (VV) vectors may increase the safety of gene delivery and extend the duration of gene expression. Although the first studies on PUV-inactivated VV (PUV-VV) for the delivery of suicide or cytokine genes to cancer cells were promising, the efficiency and kinetics of exogenous gene expression have not been fully evaluated. Furthermore, these studies should be extended to other gene therapy strategies, e.g. tumor suppressor genes. METHODS: We constructed VV recombinants carrying the luciferase (luc) gene, or the tumor suppressor p53 gene, to analyze exogenous gene expression after PUV treatment. Apoptosis induction and antitumor effects were examined in glioma cell culture and in an animal model, respectively. RESULTS: PUV-VV induced efficient PE/L-driven expression of luc and p53 exogenous genes in infected cells. A surprising prolonged p53 protein production was measured in glioma cells infected with PUV-VV expressing p53 (VV-TK-53) on Days 5-7 post-infection, reaching a maximal level of 9 microg/ml. VV-TK-53 induced apoptosis in 88% and 77.6% of infected C6 and 9L glioma cells, respectively. In contrast, 80% of cells infected with the PUV-inactivated control virus remained viable. Finally, ex vivo infection of C6 glioma cells with PUV-inactivated VV-TK-53 significantly reduced subsequent tumor growth in nude mice. CONCLUSIONS: Replication-deficient PUV-VV is safe and very efficient in prolonged foreign gene expression. Therefore PUV-VVs are recommended as vectors for applications in cancer gene therapy and recombinant vaccine development.


Assuntos
Neoplasias Encefálicas/metabolismo , Terapia Genética , Vetores Genéticos , Glioma/metabolismo , Luciferases/genética , Proteína Supressora de Tumor p53/genética , Vaccinia virus/genética , Animais , Apoptose , Neoplasias Encefálicas/induzido quimicamente , Neoplasias Encefálicas/patologia , Primers do DNA/química , Vírus Defeituosos , Ensaio de Imunoadsorção Enzimática , Glioma/induzido quimicamente , Glioma/patologia , Humanos , Luciferases/metabolismo , Camundongos , Camundongos Nus , Terapia PUVA , Ratos , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo , Replicação Viral/genética
10.
Biotechniques ; 31(3): 534, 536, 538-40, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11570497

RESUMO

Recombinant vaccinia viruses (VVs) are widely used as expression vectors in molecular biology and immunology and are now under evaluation for gene therapy. The current techniques for inserting foreign DNA into the large VV genome are based on either homologous recombination between transfer plasmids and VVgenomes or direct DNA ligation and packaging using replication-deficient poxviruses. Here, we describe efficient new versions of both methods that produce 90%-100% of the recombinant viruses. In the new homologous recombination method, VV DNA "arms" obtained by NotI digestion and intact transfer plasmids were used for co-transfection. In the direct DNA ligation method, foreign DNA was inserted into a unique NotI restriction site of the VVgenome. In both methods, the generation of recombinant viruses was carried out in cells infected with a non-replicating, psoralen-UV (PUV)-inactivated helper VV. The convenience of these new techniques is demonstrated by the construction of recombinant VVs that produce E. coli beta-galactosidase. An important feature of these strategies is that any VV strain can be used as a helper virus after PUV inactivation.


Assuntos
DNA Recombinante , Ficusina , Vetores Genéticos , Raios Ultravioleta , Vaccinia virus/genética , Southern Blotting , Linhagem Celular , DNA Viral/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Escherichia coli/enzimologia , Expressão Gênica , Plasmídeos/genética , Timidina Quinase/genética , Transfecção , beta-Galactosidase/genética
11.
Vopr Virusol ; 46(2): 41-5, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11392972

RESUMO

The role of different gB epitopes and regions at some stages of virus replication in cell cultures and in the formation of immunity to Aujeszky's disease virus (ADV) was studied using a panel of 13 monoclonal antibodies (MAB) that recognize glycoprotein gB (gB) of ADV and antisera against fusion recombinant proteins expressing gB fragments. Productive infection following virion attachment was prevented by antibodies to the N-terminal domain of gB. Three MABs against the N-terminal domain of gB and 5 MABs directed against the immunodominant region located in the gBc-subunit of gB inhibited the cell-to-cell spread of viral infection. After immunization with recombinant proteins expressing the N-terminal fragments of gB 80% mice were protected from lethal ADV challenge. After passive immunization the majority of MABs protected 20-80% mice from lethal ADV challenge. Hence, the N-terminal domain of ADV gB is associated with the virus penetration into the cell and is important for anti-ADV immunity.


Assuntos
Antígenos Virais/imunologia , Herpesvirus Suídeo 1/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Mapeamento de Epitopos , Epitopos/imunologia , Glicoproteínas/imunologia
12.
J Immunother ; 24(1): 46-57, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11211148

RESUMO

Recombinant viruses can produce cytokines in tumors mobilizing an immune response to tumor cells. In this study, the authors investigated gene expression, in vivo antitumor efficacy, and safety of attenuated recombinant vaccinia virus (rVV) carrying murine cytokine genes interleukin (IL)-2 (rVV-mIL-2), IL-12 (rVV-mIL-12), and both IL-2 and IL-12 (rVV-2-12) in an athymic nude mice model. Significant tumor inhibition (p < 0.05) was observed in a preestablished subcutaneously implanted C6 glioma model using rVVs at doses ranging from 10(2) to 10(7) plaque forming units (PFU). An antitumor effect did not depend on the dose of the rVV-mIL-2 and rVV-mIL-12 viruses. All constructed rVVs induced a high level of cytokine expression in vitro and in vivo. Most groups injected with high doses of recombinant viruses encoding cytokine genes (10(5) to 10(7) PFU) showed signs of cytokine toxicity, whereas in the low-dose treatment groups (10(2) to 10(3) PFU) toxicity was greatly reduced. The antitumor activity of rVV-mIL-12 was associated with increases in both the percentage and number of natural killer T cells in the spleen. Local detection of interferon-y and tumor necrosis factor-alpha was also correlated with tumor growth arrest induced by the treatment. High-dose VV control vector per se induced tumor inhibition by activating Mac-1+ cells in blood, but the antitumor effect was less pronounced compared with rVV-carrying cytokine genes (p < 0.05). These results suggest that attenuated recombinant strains of VV at low doses may potentially be efficient vectors for cancer immunotherapy.


Assuntos
Citocinas/genética , Citocinas/uso terapêutico , Terapia Genética , Glioma/genética , Glioma/terapia , Vaccinia virus/genética , Vaccinia virus/imunologia , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/virologia , Linhagem Celular , Chlorocebus aethiops , Modelos Animais de Doenças , Relação Dose-Resposta Imunológica , Vetores Genéticos/administração & dosagem , Vetores Genéticos/imunologia , Glioma/imunologia , Glioma/virologia , Injeções Intralesionais , Interferon gama/biossíntese , Interleucina-12/biossíntese , Interleucina-12/genética , Interleucina-2/biossíntese , Interleucina-2/genética , Ativação Linfocitária/genética , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/virologia , Masculino , Camundongos , Camundongos Nus , Especificidade de Órgãos/genética , Especificidade de Órgãos/imunologia , Ratos , Vaccinia virus/fisiologia , Replicação Viral/genética , Replicação Viral/imunologia
13.
Cancer Gene Ther ; 7(11): 1437-47, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11129286

RESUMO

Our previous studies have shown that vaccinia virus (VV) expressing p53, interleukin-2 (IL-2), and interleukin-12 (IL-12) results in an effective inhibition of subcutaneous glioma growth in mice. We propose that combination therapy of tumors with virus-mediated p53 and cytokine genes offers the prospect of synergistic antitumor response. In this work, the antitumor efficacy of VV-mediated combination of p53, IL-2, and IL-12 genes was evaluated in a nude mouse model. To minimize cytokine-associated toxicity, a virus dose as low as 10 plaque-forming units of VV expressing IL-2 and IL-12 per animal was used alone and together with 2 x 10(7) plaque-forming units of VV expressing p53. Intratumoral treatment of established C6 glioma with recombinant viruses rVV-p53, rVV-mIL2, rVV-mIL12, and rVV-2-12 induced the prolonged expression of p53, IL-2, IL-12, and both cytokines simultaneously. The combination of rVV-p53/rVV-mIL 2 or rVV-p53/rVV-2-12 resulted in significant tumor inhibition compared to single modality treatment (P<.05). rVV-p53/rVV-2-12 therapy was associated with significant elevation of natural killer, Mac-1+, and NKT cells in blood and interferon-gamma, and tumor necrosis factor-alpha expression in tumors. The difference in the inhibition of tumor growth between the rVV-p53/rVV-mIL2 combination and rVV-p53 was statistically insignificant. These data demonstrate that gene therapy based on VV-mediated combination of p53, IL-2, and IL-12 treatment may be a promising adjunctive strategy for glioma treatment.


Assuntos
Neoplasias Encefálicas/genética , Genes p53/genética , Terapia Genética/métodos , Glioma/terapia , Interleucina-12/genética , Interleucina-2/genética , Vaccinia virus/genética , Análise de Variância , Animais , Apoptose , Linhagem Celular , Citometria de Fluxo , Haplorrinos , Marcação In Situ das Extremidades Cortadas , Interferon gama/metabolismo , Interleucina-12/biossíntese , Interleucina-2/biossíntese , Células Matadoras Naturais/metabolismo , Leucócitos/metabolismo , Camundongos , Camundongos Nus , Transplante de Neoplasias , Ratos , Proteínas Recombinantes/metabolismo , Baço/citologia , Fatores de Tempo , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/metabolismo , Proteína Supressora de Tumor p53/biossíntese
14.
Microbes Infect ; 2(11): 1321-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11018448

RESUMO

Early protein 0 (EP0)-deficient recombinant Aujeszky's disease viruses, Ka-ep0lac and Ba-ep0lac derived from strains Kaplan and Bartha, respectively, were constructed to explore the impact of the mutation on replication, virulence and latency of the virus. Inactivation of the EP0 gene resulted in a mutation of long latency transcript (Cheung et al., 1991) that is located on the complementary DNA strand of EP0 and immediate early protein (IE)175 genes. In infection of immortalized porcine kidney cells, the growth rate and yield of both EP0(-) mutant strains were significantly smaller than that of wild-type virus. Ka-ep0lac was found to be highly virulent, while Ba-ep0lac showed an attenuated phenotype in mice. PCR assay and immunohistochemistry showed that the Ba-ep0lac virus was able to establish latency in the mouse trigeminal ganglia. However, latent virus was not able to reactivate in explant reactivation assays. Accordingly, latent Ba-ep0lac has the potential to be exploited as vectors for the delivery of foreign genes to the nervous system.


Assuntos
Herpesvirus Suídeo 1/fisiologia , Herpesvirus Suídeo 1/patogenicidade , Pseudorraiva/virologia , Proteínas Virais/genética , Latência Viral/genética , Animais , Linhagem Celular , DNA Recombinante , DNA Viral/genética , DNA Viral/metabolismo , Feminino , Genoma Viral , Herpesvirus Suídeo 1/genética , Dose Letal Mediana , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Plasmídeos , Suínos , Transcrição Gênica , Gânglio Trigeminal/virologia , Proteínas Virais/fisiologia , Virulência , Ativação Viral , Replicação Viral
15.
Anticancer Res ; 20(3A): 1337-42, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10928041

RESUMO

The use of interleukin-2 (IL-2) and p53 for immunotherapy and gene therapy for cancer has shown promising results. In this study, we examined the efficacy of plasmid gene therapy utilizing murine IL-2, the wild-type (wt) human p53 gene, the combination of these genes, and the murine bax gene, which are under the control of the cytomegalovirus (CMV) immediate-early promoter, in nude mice bearing established subcutaneous C6 glioma. In vitro assays and immunocytochemical analysis for therapeutic genes demonstrated expression of the proteins in C6 transfected cells. In animal studies, significant antitumor activity was observed for the IL-2, p53/IL-2, and bax treated groups. However, no synergistic effect was observed in the p53/IL-2 combination group. Demonstrating for the first time, bax showed a significant reduction of tumor volume when compared to p53 (p < 0.02). Thus, our in vivo studies show that delivery of naked therapeutic genes is safe and results in significantly slower progression of glioma in athymic rodents.


Assuntos
Glioma/terapia , Interleucina-2/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas/uso terapêutico , Proteína Supressora de Tumor p53/uso terapêutico , Análise de Variância , Animais , Modelos Animais de Doenças , Expressão Gênica , Técnicas de Transferência de Genes , Terapia Genética , Glioma/genética , Glioma/patologia , Imunoterapia , Interleucina-2/genética , Camundongos , Camundongos Nus , Transplante de Neoplasias , Proteínas Proto-Oncogênicas/genética , Ratos , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína X Associada a bcl-2
16.
J Gen Virol ; 81(Pt 2): 415-20, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10644840

RESUMO

Contradictory data have recently been reported on the role of the unique long-internal repeat junction area of pseudorabies (Aujeszky's disease) virus (PrV) genome in the virulence of the virus. To investigate the basis of the difference, four recombinant PrVs mutated at the outer region of inverted repeats that involved a putative latency promoter (P(LAT2)) were constructed in this study. Propagation characteristics of mutant viruses in cultured cells were similar to those of the wild-type virus. However, a 757 bp deletion at this location caused significant reduction in the virulence of PrV after intraperitoneal inoculation of mice and a moderate decrease in the virulence after intracranial inoculation. These results indicate that the P(LAT2) region is an important virulence determinant that may be implicated in the neuroinvasive capability of the virus.


Assuntos
Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/patogenicidade , Animais , Sequência de Bases , Primers do DNA/genética , Elementos Facilitadores Genéticos , Feminino , Genoma Viral , Herpesvirus Suídeo 1/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Regiões Promotoras Genéticas , Pseudorraiva/virologia , Deleção de Sequência , Distribuição Tecidual , Virulência/genética
17.
Acta Vet Hung ; 48(1): 125-36, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11402671

RESUMO

Previously, we sequenced the HSV-1 Ul39-Ul40 homologue genes of Aujeszky's disease virus (ADV), also designated as pseudorabies virus (Kaliman et al., 1994a, b). Now we report the nucleotide sequence of the adjacent DNA that encodes Ul38, the 5'-region (750 bp) of Ul37, and the promoter regions between these divergently arranged two genes. The ADV Ul38 gene encodes a protein of 368 amino acids. Amino acid sequence comparison of ADV Ul38 with that of other herpesviruses revealed significant structural homology. In a transcription study using RNase protection assay and Northern blot hybridization, we found that the Ul38 gene had one initiation site, but the Ul37 gene was initiated at two transcription sites with two potential initiator AUGs, one of which was dominant. Comparison of ADV Ul37, Ul38 and ribonucleotide reductase gene expression showed that these genes belong to the same temporal class with early kinetics. Data of structural and transcriptional studies suggest that regulation of the expression of these two ADV genes could differ from that of the HSV-1 virus.


Assuntos
Proteínas do Capsídeo , Capsídeo/genética , DNA Viral/genética , Herpesvirus Suídeo 1/genética , Proteínas Estruturais Virais/genética , Animais , Sequência de Bases , Northern Blotting , Capsídeo/biossíntese , Regulação da Expressão Gênica , Dados de Sequência Molecular , Suínos , Proteínas Estruturais Virais/biossíntese
18.
Acta Vet Hung ; 48(2): 229-36, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11402706

RESUMO

Gene immunization can be an effective vaccine strategy eliciting both humoral and cell-mediated immune responses. We constructed plasmid vectors expressing the full-length Vnukovo-32 rabies virus glycoprotein G under the control of CMV IE promoter and enhancer, adenovirus tripartite leader sequences and poly A signal of SV40. The gene vaccines were evaluated for the ability to elicit neutralizing antibodies and to protect BALB/c mice against lethal rabies virus challenge. First, mice were injected intramuscularly (i.m.) into the left hind leg and by the intradermoplantar (i.d.p.) route with equal amounts of plasmid DNA (0.25-0.1 mg). Two weeks later, immunization was boosted with an additional dose of the DNA. The immunized mice were challenged by intracerebral (i.c.) inoculation of CVS-27 (10-50 LD50) rabies virus. All mice produced anti-rabies virus neutralizing antibodies with a titre of > or = 1:45 after immunization with 0.1-0.4 mg of DNA. In challenge experiments, 83 to 91.6% protection was observed. These results confirm that a DNA vaccine could be a simple and effective solution for preventing the spread of rabies.


Assuntos
Antígenos Virais , Glicoproteínas/genética , Imunização/veterinária , Vírus da Raiva/genética , Raiva/prevenção & controle , Vacinas de DNA , Proteínas do Envelope Viral/genética , Animais , Feminino , Glicoproteínas/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos , Raiva/imunologia , Proteínas do Envelope Viral/biossíntese
19.
Oncol Res ; 11(3): 133-44, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10527073

RESUMO

The ability of certain viruses to lyse cancer cells suggests that they may have potential as oncolytic agents. We investigated the effect of vaccinia virus (VV) and its recombinant derivatives (recVV2, rVV-p53) on growth of C6 rat glioma cells that form fast growing tumors in athymic nude mice. VV effectively infected C6 cells in vitro, inducing high level of foreign gene expression. Most of C6 cells infected in vitro with rVV-p53 expressing the tumor suppressor p53 protein showed apoptosis specific morphological changes in DAPI-stained nuclei and DNA fragmentation pattern on gel electrophoresis; infection with VV induced low level of cell apoptosis. In an ex vivo experiment, VV-infected C6 cells were implanted s.c. in athymic nude mice and tumor development was monitored. In contrast to the control PBS group, most of mice implanted with infected cells remained tumor free until the end of the observation period. In an in vivo experiment, injection of VV or rVV-p53 after the C6 cells had been implanted in nude mice induced effective inhibition of tumor growth in comparison with control PBS groups. The oncolytic effect was greater with rVV-p53, apparently due to overexpressed p53 and p53-mediated cell apoptosis. In study of virus virulence we did not observe disease symptoms in athymic mice infected with a high dose of VV. Experimental results indicate that vaccinia virus itself and vaccinia-mediated delivery of therapeutic genes represent novel potential strategies for tumor therapy.


Assuntos
Neoplasias Encefálicas/terapia , Glioma/terapia , Proteína Supressora de Tumor p53/uso terapêutico , Vacinas Atenuadas/uso terapêutico , Vaccinia virus/imunologia , Vacinas Virais/uso terapêutico , Animais , Antineoplásicos/farmacologia , Apoptose , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/virologia , Divisão Celular , Glioma/mortalidade , Glioma/patologia , Glioma/virologia , Humanos , Camundongos , Camundongos Nus , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Taxa de Sobrevida , Distribuição Tecidual , Transplante Heterólogo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Vacinas Atenuadas/farmacologia , Vaccinia virus/genética , Vaccinia virus/patogenicidade , Proteínas Virais/genética , Proteínas Virais/metabolismo
20.
Luminescence ; 14(2): 69-74, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10398563

RESUMO

Here we report the insertion of a synthetic version of the cDNA encoding the jellyfish (Aequorea victoria) green fluorescent protein (gfph ) into the genome of pseudorabies (Aujeszky's disease) virus (PrV). A putative latency promoter (PLAT) located at the inverted repeat region of the PrV genome was chosen as the target site for the insertion. Recombinant viral DNA designated as vLAT-gfp was generated as a result of homologous recombination between the transfected viral DNA and a plasmid containing the GFP-expression cassette flanked by viral sequences homologous to the target region. Plaques containing recombinant virus were selected visually using a fluorescent microscope. We demonstrated a GFP-expression in infected neurons of rat brain which showed normal morphology at early stage of viral infection by monitoring fluorescent light emission.


Assuntos
Encéfalo/citologia , Herpesvirus Suídeo 1/genética , Proteínas Luminescentes/biossíntese , Neurônios/citologia , Animais , Linhagem Celular , DNA Complementar , Técnicas de Transferência de Genes , Proteínas de Fluorescência Verde , Herpesvirus Suídeo 1/isolamento & purificação , Proteínas Luminescentes/análise , Proteínas Luminescentes/genética , Camundongos , Regiões Promotoras Genéticas , Ratos , Proteínas Recombinantes/análise , Proteínas Recombinantes/biossíntese , Recombinação Genética , Cifozoários , Suínos , Células Tumorais Cultivadas
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