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1.
Plant Biol (Stuttg) ; 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38059684

ABSTRACT

The concurrent impacts of multiple disturbances have the potential to modify ecosystem functioning by diminishing recovery capacity and resilience. Nevertheless, it remains uncertain how plant species from tropical communities respond to the cumulative effects of drought and fire. In this study, we evaluated the responses of six plant species from campos rupestres subjected to a mild drought followed by fire and tested if plants subjected to simulated drought show reductions in carbon uptake and depletion of non-structural carbohydrate (NSC) reserves, thus constraining their resprouting. We monitored monthly variations in leaf gas exchange and aboveground biomass over 18 months. Subsequently, an accidental fire occurred in the study area, leading us to collect samples of belowground structures for NSC analyses on the day of the burn. There were no differences in the frequency of resprouting between the above two conditions. Additionally, gas exchange in most species either remained stable or increased after the fire. Drought had no adverse effects on NSC reserves in the belowground structures and may have contributed to species resprouting after fire. The impact of drought pre-conditions on post-fire aboveground biomass was generally minor for most species, except Vellozia nivea, which displayed roughly a 5% reduction in biomass following the drought. Our findings highlight the remarkable resilience of campos rupestres species, even after enduring 18 months of reduced water availability and an unintended fire event. These species demonstrated the capacity to maintain their physiological functions and resprouting capacities after a fire event, underscoring their strong recovery potential.

2.
Eur Rev Med Pharmacol Sci ; 25(8): 3365-3374, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33928624

ABSTRACT

OBJECTIVE: Healthcare workers are at risk for COVID-19 contamination. It is important to protect them in order to reduce nosocomial transmission and maintain the assistance capacity of health systems. To evaluate the diagnostic test and retest strategy with RT-PCR for SARS-CoV-2 and factors associated with the diagnosis of COVID-19 among healthcare workers. PATIENTS AND METHODS: Cross-sectional study carried out in a Brazilian hospital. From April 27 to June 16, 2020, symptomatic healthcare workers underwent an RT-PCR test on upper respiratory tract specimens as soon as possible and, if negative, it was repeated close to the 5th day of symptom evolution. Working areas were divided into assistance areas dedicated or not dedicated to COVID-19 and non-assistance areas. The type of activity was divided into assistance or non-assistance activity. RESULTS: 775 individuals were evaluated. 114 were diagnosed with COVID-19, of whom 101 followed the testing protocol. A second RT-PCR identified five (4.9%) of the positive cases. Working in an area dedicated to patients with COVID-19 was more prevalent among positive cases (35.1% x 19.8%, p=0.001) as well as working in an assistance activity (80.7% x 70.8%, p=0.031). CONCLUSIONS: A second RT-PCR test after the 5th day of symptom evolution showed limited diagnostic improvement. The adoption of a single test-based strategy, carried out at the right time after the onset of symptoms, allows the optimal use of resources. Working in a COVID-19 dedicated area and in direct contact with patients is related to a higher prevalence of COVID-19 among symptomatic healthcare workers.


Subject(s)
COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , Health Personnel , Adult , Brazil/epidemiology , COVID-19/epidemiology , COVID-19/physiopathology , Disease Progression , Female , Humans , Infectious Disease Transmission, Patient-to-Professional , Male , Middle Aged , Prevalence , SARS-CoV-2 , Time Factors
3.
Transplant Proc ; 51(2): 383-385, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30879547

ABSTRACT

The plasma cell dyscrasias (PCDs) include a number of entities such as multiple myeloma, primary amyloidosis, and monoclonal immunoglobulin deposition disease. Hematopoietic cell transplant (HCT) is the only cure for a variety of hematologic and oncologic diseases. Clinically significant renal impairment is a common feature in plasma cell myeloma, affecting 20% to 55% of patients at initial diagnosis; 2% to 3% of patients present with failure sufficiently severe to require hemodialysis. This circumstance is associated with a high early mortality. The necessity for immunosuppression after HCT could complicate its management and may precipitate the development of complications. In some patients an effective alternative could be kidney transplant (KT); however, the presence of 2 transplants will require optimal adjustment of immunosuppression and management of complications. At present, there are few published cases of KT after HCT, and the experience of managing 2 transplants is limited. We would like to describe our experience with 4 patients who had a PCD and initially received HCT and received subsequent KT. In our experience the progress and outcome of KT after HCT were optimal. We would like to address that a higher incidence of cytopenia associated with the combination of immunosuppression (lenalidomide, tacrolimus, mycophenolate, etc.) and other drugs (ie, valganciclovir) should be considered together with an increased risk of opportunistic infections and PCD relapse.


Subject(s)
Hematopoietic Stem Cell Transplantation , Kidney Transplantation , Paraproteinemias/complications , Paraproteinemias/surgery , Renal Insufficiency/surgery , Adult , Aged , Female , Humans , Immunosuppressive Agents/therapeutic use , Male , Middle Aged , Renal Insufficiency/etiology
4.
Braz J Med Biol Res ; 48(9): 843-51, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26200229

ABSTRACT

A bovine herpesvirus 1 (BoHV-1) defective in glycoprotein E (gE) was constructed from a Brazilian genital BoHV-1 isolate, by replacing the full gE coding region with the green fluorescent protein (GFP) gene for selection. Upon co-transfection of MDBK cells with genomic viral DNA plus the GFP-bearing gE-deletion plasmid, three fluorescent recombinant clones were obtained out of approximately 5000 viral plaques. Deletion of the gE gene and the presence of the GFP marker in the genome of recombinant viruses were confirmed by PCR. Despite forming smaller plaques, the BoHV-1△gE recombinants replicated in MDBK cells with similar kinetics and to similar titers to that of the parental virus (SV56/90), demonstrating that the gE deletion had no deleterious effects on replication efficacy in vitro. Thirteen calves inoculated intramuscularly with BoHV-1△gE developed virus neutralizing antibodies at day 42 post-infection (titers from 2 to 16), demonstrating the ability of the recombinant to replicate and to induce a serological response in vivo. Furthermore, the serological response induced by recombinant BoHV-1△gE could be differentiated from that induced by wild-type BoHV-1 by the use of an anti-gE antibody ELISA kit. Taken together, these results indicated the potential application of recombinant BoHV-1 △gE in vaccine formulations to prevent the losses caused by BoHV-1 infections while allowing for differentiation of vaccinated from naturally infected animals.


Subject(s)
Gene Deletion , Herpesvirus 1, Bovine/immunology , Viral Proteins/genetics , Viral Proteins/immunology , Viral Vaccines/immunology , Animals , Cattle , Electrophoresis, Polyacrylamide Gel , Herpesviridae Infections/prevention & control , Herpesviridae Infections/veterinary , Herpesvirus 1, Bovine/chemistry , Herpesvirus 1, Bovine/genetics , Immunoblotting , Polymerase Chain Reaction , Recombination, Genetic/genetics , Vaccines, Inactivated/genetics , Vaccines, Inactivated/immunology , Viral Vaccines/genetics
5.
Genet Mol Res ; 11(4): 4187-97, 2012 Dec 06.
Article in English | MEDLINE | ID: mdl-23315803

ABSTRACT

We investigated the diversity of endophytic fungi found on grape (Vitis labrusca cv. Niagara Rosada) leaves collected from Salesópolis, SP, Brazil. The fungi were isolated and characterized by amplified ribosomal DNA restriction analysis, followed by sequencing of the ITS1-5.8S-ITS2 rDNA. In addition, the ability of these endophytic fungi to inhibit the grapevine pathogen Fusarium oxysporum f. sp herbemontis was determined in vitro. We also observed that the climatic factors, such as temperature and rainfall, have no effect on the frequency of infection by endophytic fungi. The endophytic fungal community that was identified included Aporospora terricola, Aureobasidium pullulans, Bjerkandera adusta, Colletotrichum boninense, C. gloeosporioides, Diaporthe helianthi, D. phaseolorum, Epicoccum nigrum, Flavodon flavus, Fusarium subglutinans, F. sacchari, Guignardia mangiferae, Lenzites elegans, Paraphaeosphaeria pilleata, Phanerochaete sordida, Phyllosticta sp, Pleurotus nebrodensis, Preussia africana, Tinctoporellus epiniltinus, and Xylaria berteri. Among these isolates, two, C. gloeosporioides and F. flavus, showed potential antagonistic activity against F. oxysporum f. sp herbemontis. We suggest the involvement of the fungal endophyte community of V. labrusca in protecting the host plant against pathogenic Fusarium species. Possibly, some endophytic isolates could be selected for the development of biological control agents for grape fungal disease; alternatively, management strategies could be tailored to increase these beneficial fungi.


Subject(s)
Ascomycota/genetics , Basidiomycota/genetics , Endophytes/genetics , Fusarium/physiology , Plant Leaves/microbiology , Vitis/microbiology , Antibiosis , Biological Control Agents , DNA, Ribosomal Spacer/genetics , Haplotypes , Molecular Typing , Mycological Typing Techniques , Phylogeny , Plant Diseases/microbiology , RNA, Fungal/genetics , RNA, Ribosomal/genetics , Sequence Analysis, DNA
6.
Vet Microbiol ; 154(1-2): 14-22, 2011 Dec 29.
Article in English | MEDLINE | ID: mdl-22019288

ABSTRACT

A recombinant bovine herpesvirus 5 lacking thymidine kinase and glycoprotein E genes (BoHV-5gEΔTKΔ) was evaluated as a live experimental vaccine. In a first experiment, ten-months-old calves were vaccinated intramuscularly (n=9) or remained as controls (n=8) and 42 days later were challenged with BoHV-5 or BoHV-1 intranasally. The four control calves challenged with BoHV-5 developed severe depression and neurological signs and were euthanized in extremis at days 13 and 14 pos-infection (pi); the five vaccinated animals challenged with BoHV-5 remained healthy. The titers of virus shedding were reduced (p<0.01) from days 3 to 7 post-infection (pi) in vaccinated animals. Control and vaccinated calves challenged with BoHV-1 presented mild transient respiratory signs; yet the magnitude of virus shedding was reduced (p<0.05) in vaccinated animals (days 5, 9 and 11pi). In a second experiment, young calves (100-120 days-old) were vaccinated (n=15) or kept as controls (n=5) and subsequently challenged with a BoHV-1 isolate. Control calves developed moderate to severe rhinitis and respiratory distress; two were euthanized in extremis at days 5 and 9 pi, respectively. In contrast, vaccinated animals were protected from challenge and only a few developed mild and transient nasal signs. The duration and titers of virus shedding after challenge were reduced (p<0.05) in vaccinated animals comparing to controls. In both experiments, vaccinated animals developed antibodies to gE only after challenge. These results demonstrate homologous and heterologous protection and are promising towards the use of the recombinant BoHV-5gEΔTKΔ in vaccine formulations to control BoHV-5 and BoHV-1 infections.


Subject(s)
Herpesvirus 1, Bovine/pathogenicity , Herpesvirus 5, Bovine/immunology , Infectious Bovine Rhinotracheitis/prevention & control , Thymidine Kinase/genetics , Viral Envelope Proteins/genetics , Viral Vaccines/immunology , Animals , Antibodies, Viral/blood , Antibody Formation , Cattle , Female , Herpesvirus 1, Bovine/immunology , Herpesvirus 5, Bovine/enzymology , Herpesvirus 5, Bovine/genetics , Infectious Bovine Rhinotracheitis/immunology , Male , Vaccines, Attenuated/immunology , Virus Shedding
7.
Parasite ; 18(3): 219-28, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21894262

ABSTRACT

Pneumocystis pneumonia (PcP) is a serious fungal infection among immunocompromised patients. In developed countries, the epidemiology and clinical spectrum of PcP have been clearly defined and well documented. However, in most developing countries, relatively little is known about the prevalence of pneumocystosis. Several articles covering African, Asian and American countries were reviewed in the present study. PcP was identified as a frequent opportunistic infection in AIDS patients from different geographic regions. A trend to an increasing rate of PcP was apparent in developing countries from 2002 to 2010.


Subject(s)
Developing Countries/statistics & numerical data , Immunocompromised Host , Pneumocystis carinii , Pneumonia, Pneumocystis/epidemiology , Africa/epidemiology , Americas/epidemiology , Asia/epidemiology , Prevalence
8.
Vet Microbiol ; 152(3-4): 270-9, 2011 Sep 28.
Article in English | MEDLINE | ID: mdl-21640524

ABSTRACT

In this study, we examined the functional role of bovine herpesvirus type 1 (BHV-1) Us9 acidic domain residues 83-90 in the anterograde axonal transport of the virus in calves (natural host), rabbits, and in cultured neurons. A mutant virus strain lacking Us9 residues 83-90 (BHV-1 Us9 Δ83-90) and the rescued virus (BHV-1 Us9 R83-90) replicated efficiently in the nasal and ocular epithelium during primary infection and established latency in the trigeminal ganglia (TG). However, upon reactivation from latency, only the BHV-1 Us9 R83-90 virus was detected in nasal and ocular swabs of animals. In compartmentalized, rabbit primary dorsal root ganglia (DRG) neuron cultures, the Us9-deleted BHV-1, BHV-1 Us9 Δ83-90 and BHV-1 Us9 R83-90 viruses were transported efficiently in the retrograde direction. However, only the BHV-1 Us9 R83-90 virus was transported in an anterograde direction. These studies suggested that the Us9 acidic domain residues located between 83 and 90 were required for axonal anterograde transport.


Subject(s)
Axonal Transport , Herpesviridae Infections/veterinary , Herpesvirus 1, Bovine/physiology , Viral Envelope Proteins/chemistry , Viral Envelope Proteins/metabolism , Amino Acid Sequence , Animals , Cattle , Cell Line , Ganglia, Spinal/virology , Herpesviridae Infections/virology , Molecular Sequence Data , Neurons/virology , Protein Structure, Tertiary , Rabbits , Trigeminal Ganglion/virology
9.
Pesqui. vet. bras ; 31(4): 319-325, abr. 2011. graf, tab
Article in Portuguese | LILACS | ID: lil-584046

ABSTRACT

This article describes an investigation on the virulence/attenuation of bovine herpesvirus type 5 (BoHV-5) recombinants deleted in the genes encoding glycoprotein E (BoHV-5gEΔ), thymidine kinase (BoHV-5TKΔ), and both gE and TK (BoHV-5gEΔTKΔ). Seronegative calves (80 to 90 days-old) inoculated with the parental strain (SV-507/99, n=5) shed virus in nasal secretions for up to 15 days (average 10.8 days). Duration of virus shedding was 11 days for BoHV-5gΔ, 9.6 days for BoHV-5TKΔ and 6.2 days for BoHV-5gEΔTKΔ groups. The highest titers were observed between days 1 and 6 post-infection (pi) for SV-507/99 (10(6.8)TCID50/mL), 10(5.1)TCID50/mL (BoHV-5gEΔ), 10(5.9)TCID50/mL (BoHV-5TKΔ) and 10(4.7)TCID50/mL (BoHV-5gEΔTKΔ). Calves inoculated with the parental virus presented anorexia, profound apathy and loss of body condition. Two calves were euthanized in extremis on days 10 and 11 pi; infectious virus was recovered from several areas of the brain. In contrast, calves inoculated with the recombinants remained healthy and a few presented a mild and transient nasal secretion. Dexamethasone (Dx) administration at day 42 pi resulted in virus shedding by all controls calves (mean duration 3.7 days), by 2/5 of BoHV-5TKΔ calves (two days) and 2/5 of BoHV-5gEΔ (one day). No virus shedding was detected in BoHV-5gEΔTKΔ calves upon Dx treatment. PCR examination of brain sections of calves euthanized at day 30 post Dx treatment revealed the presence of latent viral DNA widely distributed in the brain of SV-507/99 calves. Latent viral DNA was detected in a few sections (3/30) of the brains of BoHV-5gEΔ calves and was not detected in the brains of calves inoculated with BoHV-5TKΔ and BoHV-5gEΔTKΔ. These results show that the single BoHV-5 mutants (gE and tk-deleted) are attenuated for calves and establish and/or reactivate latent infection inefficiently. The double mutant BoHV-5gEΔTKΔ is fully attenuated and appears not to establish or not reactivate efficiently from latent infection. Thus, these recombinants, especially the double mutant BoHV-5gEΔTKΔ, display an adequate phenotype for use in modified-live vaccine formulations.


Este artigo descreve uma investigação da virulência/atenuação de recombinantes do herpesvírus bovino tipo 5 (BoHV-5) com deleções nos genes da glicoproteína E (BoHV-5gEΔ), timidina quinase (BoHV-5TKΔ), e ambos gE e TK (BoHV-5gEΔTKΔ). Bezerros soronegativos (80-90 dias de idade) inoculados com o vírus parental SV-507/99 (n=5) excretaram o vírus em secreções nasais por até 15 dias (média de 10,8 dias). Nos animais inoculados com os recombinantes, a duração da excreção viral foi de 11 dias (BoHV-5gEΔ), 9,6 dias (BoHV-5TKΔ) e 6,2 dias (BoHV-5gEΔTKΔ). Os maiores títulos foram observados entre os dias 1 e 6 pós-inoculação (pi), sendo de 10(6,8)TCID50/mL para o SV-507/99, 10(5,1)TCID50/mL (BoHV-5gEΔ), 10(5,9)TCID50/mL (BoHV-5TKΔ) e 10(4,7)TCIΔ50/mL (BoHV-5gEΔTKΔ). Os bezerros inoculados com o vírus parental apresentaram anorexia e apatia; três deles mostraram apatia profunda e perda da condição corporal. Dois bezerros foram eutanasiados in extremis nos dias 10 e 11 pi, respectivamente e o vírus foi isolado de várias regiões do encéfalo. Já os bezerros inoculados com os recombinantes permaneceram saudáveis; alguns apresentaram uma secreção nasal serosa transitória. Administração de dexametasona (Dx) no dia 42 pi resultou em excreção viral por todos os bezerros inoculados com o vírus parental (duração média de 3,7 dias), por 2 de 5 bezerros dos grupos BoHV-5TKΔ (dois dias) e BoHV-5gEΔ (um dia). Os bezerros inoculados com o duplo mutante BoHV-5gEΔTKΔ não excretaram o vírus após o tratamento com Dx. Pesquisa de DNA viral por PCR no dia 30 pós-Dx revelou uma ampla distribuição do DNA do vírus parental no encéfalo; poucas seções (3/30) foram positivas no encéfalo dos animais do grupo BoHV-5gEΔ, e não detectou-se DNA latente no encéfalo dos animais dos grupos BoHV-5TKΔ e BoHV-5gEΔTKΔ. Esses resultados demonstram que os mutantes simples (gE and tk-deletados) são atenuados para bezerros e estabelecem e/ou reativam infecção latente ineficientemente. Já o duplo mutante BoHV-5gEΔTKΔ é atenuado e parece não estabelecer e/ou não reativar eficientemente a infecção latente. Portanto, os vírus recombinantes, e em especial o duplo mutante BoHV-5gEΔTKΔ apresentam um fenótipo compatível com a sua inclusão em vacinas vivas modificadas.


Subject(s)
Animals , Glycoproteins/adverse effects , Glycoproteins , /pathogenicity , Thymidine Kinase , Recombinant Proteins
10.
Braz. j. med. biol. res ; 43(2): 217-224, Feb. 2010. ilus, graf
Article in English | LILACS | ID: lil-538233

ABSTRACT

Bovine herpesvirus type 5 (BoHV-5) is an important pathogen of cattle in South America. We describe here the construction and characterization of deletion mutants defective in the glycoprotein E (gE) or thymidine kinase (TK) gene or both (gE/TK) from a highly neurovirulent and well-characterized Brazilian BoHV-5 strain (SV507/99). A gE-deleted recombinant virus (BoHV-5 gE∆) was first generated in which the entire gE open reading frame was replaced with a chimeric green fluorescent protein gene. A TK-deleted recombinant virus (BoHV-5 TK∆) was then generated in which most of the TK open reading frame sequences were deleted and replaced with a chimeric â-galactosidase gene. Subsequently, using the BoHV-5 gE∆ virus as backbone, a double gene-deleted (TK plus gE) BoHV-5 recombinant (BoHV-5 gE/TK∆) was generated. The deletion of the gE and TK genes was confirmed by immunoblotting and PCR, respectively. In Madin Darby bovine kidney (MDBK) cells, the mutants lacking gE (BoHV-5 gE∆) and TK + gE (BoHV-5 gE/TK∆) produced small plaques while the TK-deleted BoHV-5 produced wild-type-sized plaques. The growth kinetics and virus yields in MDBK cells for all three recombinants (BoHV-5 gE∆, BoHV-5 TK∆ and BoHV-5 gE/TK∆) were similar to those of the parental virus. It is our belief that the dual gene-deleted recombinant (BoHV-5 gE/TK∆) produced on the background of a highly neurovirulent Brazilian BoHV-5 strain may have potential application in a vaccine against BoHV-5.


Subject(s)
Animals , Cattle , Gene Deletion , /genetics , Thymidine Kinase/genetics , Viral Envelope Proteins/genetics , Defective Viruses/genetics , Electrophoresis, Polyacrylamide Gel , Green Fluorescent Proteins/genetics , /immunology , /pathogenicity , Immunoblotting , Polymerase Chain Reaction , Recombination, Genetic/genetics , Thymidine Kinase/immunology , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology , Viral Envelope Proteins/immunology , Viral Vaccines/genetics , Viral Vaccines/immunology , Virulence/genetics
11.
Braz. j. med. biol. res ; 43(2): 150-159, Feb. 2010. tab, ilus
Article in English | LILACS | ID: lil-538237

ABSTRACT

Bovine herpesvirus 5 (BoHV-5), the agent of herpetic meningoencephalitis in cattle, is an important pathogen of cattle in South America and several efforts have been made to produce safer and more effective vaccines. In the present study, we investigated in rabbits the virulence of three recombinant viruses constructed from a neurovirulent Brazilian BoHV-5 strain (SV507/99). The recombinants are defective in glycoprotein E (BoHV-5gEÄ), thymidine kinase (BoHV-5TKÄ) and both proteins (BoHV-5gEÄTKÄ). Rabbits inoculated with the parental virus (N = 8) developed neurological disease and died or were euthanized in extremis between days 7 and 13 post-infection (pi). Infectivity was detected in several areas of their brains. Three of 8 rabbits inoculated with the recombinant BoHV-5gEÄ developed neurological signs between days 10 and 15 pi and were also euthanized. A more restricted virus distribution was detected in the brain of these animals. Rabbits inoculated with the recombinants BoHV-5TKÄ (N = 8) or BoHV-5gEÄTKÄ (N = 8) remained healthy throughout the experiment in spite of variable levels of virus replication in the nose. Dexamethasone (Dx) administration to rabbits inoculated with the three recombinants at day 42 pi did not result in viral reactivation, as demonstrated by absence of virus shedding and/or increase in virus neutralizing titers. Nevertheless, viral DNA was detected in the trigeminal ganglia or olfactory bulbs of all animals at day 28 post-Dx, demonstrating they were latently infected. These results show that recombinants BoHV-5TKÄ and BoHV-5gEÄTKÄ are attenuated for rabbits and constitute potential vaccine candidates upon the confirmation of this phenotype in cattle.


Subject(s)
Animals , Rabbits , Herpesviridae Infections/virology , /pathogenicity , Herpesvirus Vaccines/immunology , Viral Envelope Proteins/immunology , Viral Proteins/immunology , Brain/virology , DNA, Viral/analysis , Dexamethasone/pharmacology , Glucocorticoids/pharmacology , Herpesviridae Infections/immunology , Herpesviridae Infections/prevention & control , /genetics , /immunology , Mutation , Thymidine Kinase/genetics , Virus Replication , Vaccines, Attenuated/immunology , Vaccines, Synthetic/immunology , Virulence/genetics , Virus Activation/drug effects
12.
Braz J Med Biol Res ; 43(2): 150-9, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20027480

ABSTRACT

Bovine herpesvirus 5 (BoHV-5), the agent of herpetic meningoencephalitis in cattle, is an important pathogen of cattle in South America and several efforts have been made to produce safer and more effective vaccines. In the present study, we investigated in rabbits the virulence of three recombinant viruses constructed from a neurovirulent Brazilian BoHV-5 strain (SV507/99). The recombinants are defective in glycoprotein E (BoHV-5gEDelta), thymidine kinase (BoHV-5TKDelta) and both proteins (BoHV-5gEDeltaTKDelta). Rabbits inoculated with the parental virus (N = 8) developed neurological disease and died or were euthanized in extremis between days 7 and 13 post-infection (pi). Infectivity was detected in several areas of their brains. Three of 8 rabbits inoculated with the recombinant BoHV-5gEDelta developed neurological signs between days 10 and 15 pi and were also euthanized. A more restricted virus distribution was detected in the brain of these animals. Rabbits inoculated with the recombinants BoHV-5TKDelta (N = 8) or BoHV-5gEDeltaTKDelta (N = 8) remained healthy throughout the experiment in spite of variable levels of virus replication in the nose. Dexamethasone (Dx) administration to rabbits inoculated with the three recombinants at day 42 pi did not result in viral reactivation, as demonstrated by absence of virus shedding and/or increase in virus neutralizing titers. Nevertheless, viral DNA was detected in the trigeminal ganglia or olfactory bulbs of all animals at day 28 post-Dx, demonstrating they were latently infected. These results show that recombinants BoHV-5TKDelta and BoHV-5gEDeltaTKDelta are attenuated for rabbits and constitute potential vaccine candidates upon the confirmation of this phenotype in cattle.


Subject(s)
Herpesviridae Infections/virology , Herpesvirus 5, Bovine/pathogenicity , Herpesvirus Vaccines/immunology , Viral Envelope Proteins/immunology , Viral Proteins/immunology , Animals , Brain/virology , DNA, Viral/analysis , Dexamethasone/pharmacology , Glucocorticoids/pharmacology , Herpesviridae Infections/immunology , Herpesviridae Infections/prevention & control , Herpesvirus 5, Bovine/genetics , Herpesvirus 5, Bovine/immunology , Mutation , Rabbits , Thymidine Kinase/genetics , Vaccines, Attenuated/immunology , Vaccines, Synthetic/immunology , Virulence/genetics , Virus Activation/drug effects , Virus Replication
13.
Braz J Med Biol Res ; 43(2): 217-24, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19893987

ABSTRACT

Bovine herpesvirus type 5 (BoHV-5) is an important pathogen of cattle in South America. We describe here the construction and characterization of deletion mutants defective in the glycoprotein E (gE) or thymidine kinase (TK) gene or both (gE/TK) from a highly neurovirulent and well-characterized Brazilian BoHV-5 strain (SV507/99). A gE-deleted recombinant virus (BoHV-5 gE) was first generated in which the entire gE open reading frame was replaced with a chimeric green fluorescent protein gene. A TK-deleted recombinant virus (BoHV-5 TK) was then generated in which most of the TK open reading frame sequences were deleted and replaced with a chimeric beta-galactosidase gene. Subsequently, using the BoHV-5 gE virus as backbone, a double gene-deleted (TK plus gE) BoHV-5 recombinant (BoHV-5 gE/TK) was generated. The deletion of the gE and TK genes was confirmed by immunoblotting and PCR, respectively. In Madin Darby bovine kidney (MDBK) cells, the mutants lacking gE (BoHV-5 gE) and TK + gE (BoHV-5 gE/TK) produced small plaques while the TK-deleted BoHV-5 produced wild-type-sized plaques. The growth kinetics and virus yields in MDBK cells for all three recombinants (BoHV-5 gE, BoHV-5 TK and BoHV-5 gE/TK) were similar to those of the parental virus. It is our belief that the dual gene-deleted recombinant (BoHV-5 gE/TK) produced on the background of a highly neurovirulent Brazilian BoHV-5 strain may have potential application in a vaccine against BoHV-5.


Subject(s)
Gene Deletion , Herpesvirus 5, Bovine/genetics , Thymidine Kinase/genetics , Viral Envelope Proteins/genetics , Animals , Cattle , Defective Viruses/genetics , Electrophoresis, Polyacrylamide Gel , Green Fluorescent Proteins/genetics , Herpesvirus 5, Bovine/immunology , Herpesvirus 5, Bovine/pathogenicity , Immunoblotting , Polymerase Chain Reaction , Recombination, Genetic/genetics , Thymidine Kinase/immunology , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology , Viral Envelope Proteins/immunology , Viral Vaccines/genetics , Viral Vaccines/immunology , Virulence/genetics
14.
Arq. bras. med. vet. zootec ; 61(4): 927-934, ago. 2009. tab, ilus
Article in Portuguese | LILACS | ID: lil-524449

ABSTRACT

Avaliou-se a produtividade do capim-elefante anão e do tifton 85 sob pastejo contínuo no noroeste do Rio Grande do Sul, utilizando-se 12 vacas da raça Holandesa, multíparas e com cerca de 100 dias de lactação. Foi aplicada a técnica dos animais reguladores para ajustes da carga animal de forma a manter a oferta de lâminas foliares de 4 por cento. No primeiro ano experimental, o capim-elefante anão e o tifton 85 apresentaram diferenças significativas quanto às taxas médias de acúmulo de lâminas foliares (31,2 vs 22,6kg/ha/dia) e produção animal (17,4 vs 20kg de leite/vaca/dia). No segundo, o tifton 85 foi superior ao capim-elefante anão quanto à taxa de acúmulo de matéria seca de lâminas foliares (38,8 vs 21,9kg/ha/dia), capacidade de suporte (2157 vs 1084kg de peso vivo/ha) e produções por área (70 vs 41,3kg de leite/ha/dia). No segundo ano, em relação ao primeiro, o tifton 85 manteve 88 por cento da capacidade de suporte e 80 por cento da produção por área, enquanto o capim-elefante anão apenas 46 por cento e 56 por cento. A produção média de 17kg de leite/vaca/dia indica um potencial pouco explorado das gramíneas tropicais em sistemas de produção de leite, especialmente na região Sul do Brasil.


Productivity of dwarf elephantgrass (Pennisetum purpureum Schum. cv. Mott) and tifton 85 (Cynodon dactylon x Cynodon nlemfuensis) pastures was evaluated under continuous grazing, in the Northwest area of Rio Grande do Sul. Twelve multiparous Holstein cows, at 100 days of lactation were evaluated and the put-and-take technique was used to regulate the stocking rate to maintain 4 percent of leaf lamina on offer. In the first year, dwarf elephantgrass and tifton 85 were different in leaf accumulation rates (31.2 vs 22.6kg/ha/day) and animal production (17.4 vs 20kg of milk/cow/day). In the second year, tifton 85 had higher leaf accumulation rates (38.8 vs 21.9kg/ha/day), stocking rate (2,157 vs 1,084kg of live weight/ha), and production per area (70 vs 41.3kg of milk/ha/day) than dwarf elephantgrass. Comparing the second to the first years, tifton 85 maintained 88 percent of stocking rate and 80 percent of production per area, while dwarf elephantgrass only 46 percent and 56 percent, respectively. Average individual production of 17kg of milk/cow/day indicates an unexplored potential of tropical grasses in dairy production systems, especially in the South of Brazil.

15.
J Virol ; 82(15): 7432-42, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18480434

ABSTRACT

Bovine herpesvirus type 1 (BHV-1) is an important component of the bovine respiratory disease complex (BRDC) in cattle. The ability of BHV-1 to transport anterogradely from neuronal cell bodies in trigeminal ganglia (TG) to nerve ending in the noses and corneas of infected cattle following reactivation from latency plays a significant role in the pathogenesis of BRDC and maintenance of BHV-1 in the cattle population. We have constructed a BHV-1 bacterial artificial chromosome (BAC) clone by inserting an excisable BAC plasmid sequence in the long intergenic region between the glycoprotein B (gB) and UL26 genes. A BAC-excised, reconstituted BHV-1 containing only the 34-bp loxP sequence within the gB-UL26 intergenic region was highly infectious in calves, retained wild-type virulence properties, and reactivated from latency following treatment with dexamethasone. Using a two-step Red-mediated mutagenesis system in Escherichia coli, we constructed a gE cytoplasmic tail-truncated BHV-1 and a gE-rescued BHV-1. Following primary infection, the gE cytoplasmic tail-truncated virus was efficiently transported retrogradely from the nerve endings in the nose and eye to cell bodies in the TG of calves and rabbits. However, following dexamethasone-induced reactivation from latency, the gE mutant virus was not isolated from nasal and ocular sheddings. Reverse transcriptase PCR assays detected VP5 transcription in the TG of rabbits infected with gE-rescued and gE cytoplasmic tail-truncated viruses during primary infection and after dexamethasone treatment but not during latency. Therefore, the BHV-1gE cytoplasmic tail-truncated virus reactivated in the TG; however, it had defective anterograde transport from TG to nose and eye in calves and rabbits.


Subject(s)
Herpesviridae Infections/virology , Herpesvirus 1, Bovine/pathogenicity , Neurons/virology , Viral Envelope Proteins/physiology , Animals , Cattle , Chromosomes, Artificial, Bacterial , Dexamethasone/administration & dosage , Eye/virology , Herpesvirus 1, Bovine/genetics , Infectious Bovine Rhinotracheitis/virology , Mutant Proteins/metabolism , Nose/virology , Rabbits , Recombination, Genetic , Sequence Deletion , Trigeminal Ganglion/virology , Viral Envelope Proteins/genetics , Viral Proteins , Virulence , Virus Activation , Virus Shedding
16.
Minerva Stomatol ; 57(3): 127-31, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18427381

ABSTRACT

Osteomas are benign tumors that consist mainly of mature compact or cancellous bone. The most common site in maxillofacial complex is the mandible, particularly the angle, followed by sinuses. The authors report a case of an ivory osteoma of the paranasal sinus in a 16 year-old male patient. The lesion was located in the left paranasal sinus (frontal, ethmoidal and maxillary), obstructing the nasolacrimal duct, resulting in dacryocystitis and frontal mucocele. The ethmoid and orbital portions were approached and excised through a Weber-Ferguson incision and maxillary osteotomy was carried out to remove the ivory osteoma, considering its location in the central and deep region of the face. After tumor removal and drainage of frontal and ethmoidal sinuses, the bone flap was repositioned using titanium microplates and screws. Soft tissue was then sutured. The patient was seen again at 3 weeks, 3 months and 2 years after surgery. Overall, he showed a good recovery and wound healing. A multispeciality team approach is advisable in such cases if radical excision is necessary. A craniofacial approach made radical single stage excision of this multicompartmental ivory osteoma possible with an uneventful postoperative period.


Subject(s)
Osteoma/surgery , Paranasal Sinus Neoplasms/surgery , Adolescent , Humans , Male , Oral Surgical Procedures/methods , Osteotomy/methods
17.
Virus Res ; 129(2): 191-9, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17822796

ABSTRACT

Bovine herpesviruses type 1 and 5 (BoHV-1 and BoHV-5) are closely related yet differ markedly in their neuropathogenic potential. BoHV-1 isolates have been associated with respiratory and genital disease whereas BoHV-5 has been consistently isolated from neurological infection. We report the characterization of five Brazilian BoHV-1 isolates associated with neurological disease, an unusual finding. All five viruses were isolated from the brain of cattle presenting neurological disease, yet prominent histological encephalitis was not observed in three cases. The isolated viruses were identified as BoHV-1 by a glycoprotein C gene-based PCR able to differentiate BoHV-1 from BoHV-5. The identity of the isolates was confirmed by nucleotide sequencing of the amplicons and by restriction analysis of PCR products from another gC region. Monoclonal antibody binding and cross-neutralization assays with BoHV-1 and BoHV-5 antisera showed a typical BoHV-1 antigenic profile. Lastly, inoculation of rabbits with these five BoHV-1 isolates did not result in neurological disease, contrasting with fatal meningoencephalitis produced by BoHV-5. Thus, the involvement of BoHV-1 in neurological disease of cattle is more frequent than previously reported, indicating the need for fast and precise means of differentiating it from BoHV-5. Likewise, the potential role of BoHV-1 in neurological infection in cattle should be further investigated.


Subject(s)
Antigens, Viral/immunology , Brain/virology , Cattle Diseases/virology , Herpesviridae Infections/veterinary , Herpesvirus 1, Bovine/genetics , Herpesvirus 1, Bovine/immunology , Nervous System Diseases/veterinary , Animals , Base Sequence , Brazil , Cattle , Herpesviridae Infections/virology , Herpesvirus 1, Bovine/isolation & purification , Herpesvirus 1, Bovine/pathogenicity , Herpesvirus 5, Bovine/genetics , Herpesvirus 5, Bovine/immunology , Herpesvirus 5, Bovine/isolation & purification , Molecular Sequence Data , Nervous System Diseases/virology , Rabbits
18.
Vet Microbiol ; 121(3-4): 257-67, 2007 Apr 15.
Article in English | MEDLINE | ID: mdl-17267142

ABSTRACT

The ability of alphaherpesviruses to infect different ruminant species may have important implications for control/eradication efforts. Serological data indicate that goats may be naturally infected with bovine herpesviruses. To investigate the susceptibility of goats to bovine herpesvirus-5 (BoHV-5), 3-4-month-old kids were inoculated intranasally with each of three Brazilian BoHV-5 isolates (G1, n=8; G2, n=5; G3, n=5). The acute infection was characterized by virus shedding in nasal secretions for up to 14 days (titers up to 10(5.97)TCID(50)/mL), mild respiratory signs and conjunctivitis. All animals seroconverted to BoHV-5, developing virus neutralizing (VN) titers from 4 to 32 to the homologous viruses. At day 60 post inoculation (pi), two animals from each group were euthanized for tissue collection and the remaining goats were submitted to dexamethasone administration (0.4 mg kg(-1) for 5 days). Dexamethasone treatment resulted in virus reactivation in 9 out of 12 animals, as ascertained by virus shedding and/or by increase in VN titers. Virus shedding was detected in 8/12 animals and lasted from 1 to 9 days. Latent viral DNA was detected by PCR in the olfactory bulb and/or trigeminal ganglia of 6/6 goats euthanized at day 60 pi and in 12/12 animals euthanized 40 days post-dexamethasone. These results show that young goats are susceptible to BoHV-5 and may shed virus upon reactivation of latent infection. Thus, it is reasonable to expect that goats raised in close contact with cattle in areas where BoHV-5 is endemic may be infected and therefore should be considered potential reservoirs of the virus.


Subject(s)
Encephalitis, Viral/veterinary , Encephalitis, Viral/virology , Goat Diseases/virology , Herpesviridae Infections/veterinary , Herpesviridae Infections/virology , Herpesvirus 5, Bovine/physiology , Meningoencephalitis/veterinary , Animals , Antibodies, Viral/blood , DNA, Viral/chemistry , DNA, Viral/genetics , Dexamethasone/pharmacology , Encephalitis, Viral/immunology , Glucocorticoids/pharmacology , Goat Diseases/immunology , Goats , Herpesviridae Infections/immunology , Herpesvirus 5, Bovine/genetics , Herpesvirus 5, Bovine/growth & development , Meningoencephalitis/immunology , Meningoencephalitis/virology , Nasal Mucosa/virology , Neutralization Tests/veterinary , Polymerase Chain Reaction/veterinary , Random Allocation , Virus Latency , Virus Shedding/immunology
19.
Int J Oral Maxillofac Surg ; 35(10): 965-8, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16829032

ABSTRACT

Low-grade myofibroblastic sarcoma was recently described as representing malignant mesenchymal tumours that show myofibroblastic differentiation; few cases have been reported. Here, a low-grade myofibroblastic sarcoma of the parapharyngeal space is described. A 42-year-old man presented with swelling on the right side of the temporal bone. Based on histological and immunohistochemical features, the diagnosis of low-grade myofibroblastic sarcoma was established. The tumour had invaded the orbit and the brain, and therefore surgical excision was not possible. There are thought to have been no cases affecting this region reported previously in the English-language literature.


Subject(s)
Head and Neck Neoplasms/pathology , Neoplasms, Muscle Tissue/pathology , Sarcoma/pathology , Adult , Diagnosis, Differential , Fatal Outcome , Head and Neck Neoplasms/therapy , Humans , Male , Neoplasms, Muscle Tissue/therapy , Rare Diseases/pathology , Rare Diseases/therapy , Sarcoma/therapy
20.
Braz J Med Biol Res ; 39(7): 935-44, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16862285

ABSTRACT

Calves born persistently infected with non-cytopathic bovine viral diarrhea virus (ncpBVDV) frequently develop a fatal gastroenteric illness called mucosal disease. Both the original virus (ncpBVDV) and an antigenically identical but cytopathic virus (cpBVDV) can be isolated from animals affected by mucosal disease. Cytopathic BVDVs originate from their ncp counterparts by diverse genetic mechanisms, all leading to the expression of the non-structural polypeptide NS3 as a discrete protein. In contrast, ncpBVDVs express only the large precursor polypeptide, NS2-3, which contains the NS3 sequence within its carboxy-terminal half. We report here the investigation of the mechanism leading to NS3 expression in 41 cpBVDV isolates. An RT-PCR strategy was employed to detect RNA insertions within the NS2-3 gene and/or duplication of the NS3 gene, two common mechanisms of NS3 expression. RT-PCR amplification revealed insertions in the NS2-3 gene of three cp isolates, with the inserts being similar in size to that present in the cpBVDV NADL strain. Sequencing of one such insert revealed a 296-nucleotide sequence with a central core of 270 nucleotides coding for an amino acid sequence highly homologous (98%) to the NADL insert, a sequence corresponding to part of the cellular J-Domain gene. One cpBVDV isolate contained a duplication of the NS3 gene downstream from the original locus. In contrast, no detectable NS2-3 insertions or NS3 gene duplications were observed in the genome of 37 cp isolates. These results demonstrate that processing of NS2-3 without bulk mRNA insertions or NS3 gene duplications seems to be a frequent mechanism leading to NS3 expression and BVDV cytopathology.


Subject(s)
Cytopathogenic Effect, Viral/genetics , Diarrhea Viruses, Bovine Viral/genetics , Gene Duplication , Genome, Viral/genetics , Viral Nonstructural Proteins/genetics , Amino Acid Sequence , Animals , Cattle , Diarrhea Viruses, Bovine Viral/isolation & purification , Gene Rearrangement , Molecular Sequence Data , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction
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