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1.
Clin Radiol ; 75(2): 100-107, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31515052

RESUMO

AIM: To analyse changes in post-neoadjuvant follow-up magnetic resonance imaging (MRI) staging accuracy for malignant adenopathies in rectal cancer, by comparing size criteria with morphological criteria using high-resolution T2-weighted sequences, as well as variations when adding diffusion-weighted imaging. METHODS AND MATERIALS: The present study was a cross-sectional study of a database including 46 1.5-T MRI examinations (2011-2016) from patients with biopsy-proven rectal cancer and chemoradiotherapy treatment before surgery. All cases were reviewed by three radiologists individually, who were blinded to any clinical information. The radiologists were experienced in rectal cancer (3-6 years) and evaluated the presence of malignant nodes in each patient. Malignancy was determined using morphological, size (5 mm), and diffusion criteria separately, as well as morphology plus diffusion. Each case was assessed four times: (1) evaluation of morphological criteria; (2) size criteria; (3) evaluation only using diffusion (b-values 50, 400, and 800); and (4) diffusion plus morphological criteria. Histological staging of surgical specimens was the reference standard. Statistical analysis included accuracy (area under the receiver operating characteristic [ROC] curve [AUC]), sensitivity, specificity, and positive/negative predictive values (PPV/NPV) for each radiologist, and group agreement (Fleiss' kappa). RESULTS: Mean values using morphological criteria were: AUC 0.78, sensitivity 77.7%, specificity 73.8%, PPV 66.1%, NPV 85.2%. Using size criterion: AUC 0.75, sensitivity 62.9%, specificity 83.2%, PPV 74.1%, NPV 80%. Added diffusion yielded no improvement, and yielded worse results by itself. CONCLUSIONS: Although morphological criteria showed better results in accuracy, sensitivity, and NPV, size criterion yielded the best specificity and PPV. Adding diffusion did not demonstrate a clear advantage over the criteria by themselves. Thus, mixed size-morphology criteria could have the greatest diagnostic value for follow-up N-staging.


Assuntos
Neoplasias Retais/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia , Estudos Transversais , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Metástase Linfática/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Med Oral Patol Oral Cir Bucal ; 22(4): e400-e409, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28578369

RESUMO

BACKGROUND: When considering dental implant rehabilitation in atrophic posterior sectors, the maxillary sinuses must be evaluated in detail. Knowledge of the anatomical variations and of the potential lesions found in these structures conditions the outcome of sinus lift procedures and therefore of the dental implants. A systematic review is made to determine the frequency of anatomical variations and pathological findings in maxillary sinuses among patients subjected to cone beam computed tomography (CBCT). MATERIAL AND METHODS: A PubMed (MEDLINE) literature search was made of articles published up until 20 December 2015. The systematic review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). The quality of the studies included in the review was assessed using the Methodological Index for Nonrandomized Studies (MINORS). RESULTS: The combinations of search terms resulted in a list of 3482 titles. Twenty-three studies finally met the inclusion criteria and were entered in the systematic review, comprising a total of 11,971 patients. The most common anatomical variations were pneumatization and sinus septa. The prevalence of maxillary sinus disease ranged from 7.5% to 66%. The most common pathological findings of the maxillary sinus were mucosal thickening, sinusitis and sinus opacification. CONCLUSIONS: Although the main indication of CBCT of the maxillary sinus in dentistry is sinus floor elevation/treatment planning and evaluation prior to dental implant placement, this imaging modality is increasingly also used for endodontic and periodontal purposes. There is no consensus regarding the cutoff point beyond which mucosal thickening of the maxillary sinus should be regarded as pathological, and the definition of maxillary sinusitis moreover varies greatly in the scientific literature. In this regard, international consensus is required in relation to these concepts, with a clear distinction between healthy and diseased maxillary sinuses.


Assuntos
Variação Anatômica , Tomografia Computadorizada de Feixe Cônico , Seio Maxilar/diagnóstico por imagem , Doenças dos Seios Paranasais/diagnóstico por imagem , Humanos
3.
Med Oral Patol Oral Cir Bucal ; 21(3): e392-402, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26946199

RESUMO

BACKGROUND: Short implants (< 10 mm) are one of the treatment options available in cases of limited vertical bone. Although such implants are now widely used, there is controversy regarding their clinical reliability. The purpose of this paper is to evaluate the predictability of short implants as an alternative to technically more complex treatments in patients with atrophic maxillae, based on a systematic review of the literature and the analysis of the implant survival rates, changes in peri-implant bone level, and associated complications. It is postulated that short implants offer clinical results similar to those of longer implants. MATERIAL AND METHODS: A Medline-PubMed search was made covering the period between January 2004 and December 2014 (both included). Studies in English published in indexed journals, involving at least 20 implants and with a follow-up period of at least 12 months were considered. A manual search in four high impact journals was also conducted. RESULTS: A total of 37 studies meeting the inclusion criteria were included in this review. 9792 implants placed in over 5000 patients were analyzed. CONCLUSIONS: Based on the results of this review, short implants are seen to offer clinical results in terms of survival, bone loss and complications similar to those of longer implants.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Atrofia , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Humanos , Maxila , Reprodutibilidade dos Testes
4.
Med Intensiva ; 40(6): 364-70, 2016.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26746125

RESUMO

UNLABELLED: Central vascular cannulation is not a risk-free procedure, especially in pediatric patients. Newborn and infants are small and low-weighted, their vascular structures have high mobility because of tissue laxity and their vessels are superficial and with small diameter. These characteristics, together with the natural anatomical variability and poor collaboration of small children, make this technique more difficult to apply. Therefore, ultrasound imaging is increasingly being used to locate vessels and guide vascular access in this population. OBJECTIVE: (a) To present a model that simulates the vascular system for training ultrasound-guided vascular access in pediatrics patients; (b) to ultrasound-guided vascular cannulation in the model. RESULTS: The model consisted of two components: (a) muscular component: avian muscle, (b) vascular component: elastic tube-like structure filled with fluid. 864 ecoguided punctures was realized in the model at different vessel depth and gauge measures were simulated, for two medical operators with different degree of experience. The average depth and diameter of vessel cannulated were 1.16 (0.42)cm and 0.43 (0.1)cm, respectively. The average number of attempts was of 1.22 (0.62). The percentage of visualization of the needle was 74%. The most frequent maneuver used for the correct location, was the modification of the angle of the needle and the relocation of the guidewire in 24% of the cases. The average time for the correct cannulations was 41 (35.8)s. The more frequent complications were the vascular perforation (11.9%) and the correct vascular puncture without possibility of introducing the guidewire (1.2%). The rate of success was 96%. CONCLUSIONS: The model simulates the anatomy (vascular and muscular structures) of a pediatric patient. It is cheap models, easily reproducible and a useful tool for training in ultrasound-guided puncture and cannulation.


Assuntos
Cateterismo Venoso Central/métodos , Modelos Biológicos , Ultrassonografia/métodos , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
5.
Sci Total Environ ; 948: 174725, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39009158

RESUMO

The ubiquitous presence of nanoplastics (NPLs) in the environment is considered of great health concern. Due to their size, NPLs can cross both the intestinal and pulmonary barriers and, consequently, their presence in the blood compartment is expected. Understanding the interactions between NPLs and human blood components is required. In this study, to simulate more adequate real exposure conditions, the whole blood of healthy donors was exposed to five different NPLs: three polystyrene NPLs of approximately 50 nm (aminated PS-NH2, carboxylated PS-COOH, and pristine PS- forms), together with two true-to-life NPLs from polyethylene terephthalate (PET) and polylactic acid (PLA) of about 150 nm. Internalization was determined in white blood cells (WBCs) by confocal microscopy, once the different main cell subtypes (monocytes, polymorphonucleated cells, and lymphocytes) were sorted by flow cytometry. Intracellular reactive oxygen species (iROS) induction was determined in WBCs and cytokine release in plasma. In addition, hemolysis, coagulation, and platelet activation were also determined. Results showed a differential uptake between WBC subtypes, with monocytes showing a higher internalization. Regarding iROS, lymphocytes were those with higher levels, which was observed for different NPLs. Changes in cytokine release were also detected, with higher effects observed after PLA- and PS-NH2-NPL exposure. Hemolysis induction was observed after PS- and PS-COOH-NPL exposure, but no effects on platelet functionality were observed after any of the treatments. To our knowledge, this is the first study comprehensively evaluating the bloodstream kinetics and toxicity of NPL from different polymeric types on human whole blood, considering the role played by the cell subtype and the NPLs physicochemical characteristics in the effects observed after the exposures.

6.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38508376

RESUMO

OBJECTIVE: To analyze the clinical, quality of life, and healthcare quality outcomes obtained in a series of patients undergoing total hip arthroplasty (THA), who were empowered and monitored using the AVIP application. These results will be compared with a control group followed through a standard protocol. MATERIAL AND METHOD: Randomized clinical trial with parallel groups involving patients with an indication for THA. Clinical variables were measured and compared using the WOMAC and mHHS, pain assessed by the VAS, quality of life with the SF-12 test. Walking capabilities were analyzed using the Functional Gait Assessment Scale, along with satisfaction levels assessed through the SUCE questionnaire, and perceived anxiety levels related to the process. RESULTS: A total of 68 patients were evaluated, with 31 patients in the AVIP group and 33 in the Control group completing the follow-up. Both groups demonstrated improvement in clinical outcomes based on the WOMAC and mHHS hip tests, a reduction in perceived pain, and an enhancement in quality of life according to the SF-12 test. Patients in the AVIP study group exhibited non-inferiority in clinical outcomes and satisfaction compared to the control group, as well as lower anxiety levels and improved walking capabilities after the first month of follow-up. Notably, 82.25% of the follow-up visits for this group were conducted remotely. CONCLUSION: The implementation of a mHealth application like AVIP can be safely offered to selected patients undergoing hip arthroplasty, enabling effective monitoring and providing continuous information and training.

7.
Science ; 215(4531): 405-7, 1982 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-6276975

RESUMO

Plasma of cattle infected with bovine leukemia virus contains a soluble factor that blocks the expression of the viral genome in cultured lymphocytes. The blocking factor is not present in plasma of bovine leukemia virus-free cattle or of cattle infected with common bovine viruses. Blocking of bovine leukemia virus expression by the plasma factor is reversible, and seems to be mediated by a nonimmunoglobulin protein molecule.


Assuntos
Doenças dos Bovinos/sangue , Vírus da Leucemia Bovina/genética , Leucemia/sangue , Retroviridae/genética , Animais , Proteínas Sanguíneas/farmacologia , Bovinos , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Linfócitos/microbiologia , Proteínas Virais/biossíntese , Proteínas Virais/genética , Replicação Viral
8.
Science ; 213(4511): 1014-6, 1981 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-6267692

RESUMO

Milk or viable milk cells collected from 24 dairy cattle naturally infected with bovine leukemia virus were inoculated into lambs, which were subsequently examined for the development of infection. With this bioassay, infectious virus was demonstrated in the milk of 17 of the cows. Bovine leukemia virus is leukemogenic in at least two mammalian species, is widespread in commercial dairy herds, and can infect a wide range of hosts in vivo and cells, including human cells, in vitro.


Assuntos
Vírus da Leucemia Bovina , Leite/microbiologia , Retroviridae , Animais , Anticorpos Antivirais/biossíntese , Bioensaio , Bovinos , Vírus da Leucemia Bovina/imunologia , Leucemia Experimental/transmissão , Linfócitos/microbiologia , Leite/citologia , Retroviridae/imunologia , Ovinos
9.
Science ; 192(4243): 1005-7, 1976 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-179141

RESUMO

Reverse transcripts of the rna genome of the bovine leukemia virus (BLV) as well as 125I-labeled BLV RNA hybridize to the DNA of tissues from leukemic cattle with the adult form of the disease but not to bovine thymic lymphoma or normal bovine tissues.


Assuntos
Doenças dos Bovinos/microbiologia , Vírus da Leucemia Bovina , Leucemia/veterinária , Retroviridae , Animais , Bovinos , Linhagem Celular , DNA Viral/análise , Leucemia/análise , Leucemia/microbiologia , Vírus da Leucemia Bovina/análise , Linfoma/microbiologia , Linfoma/veterinária , Hibridização de Ácido Nucleico , Retroviridae/análise , Neoplasias do Timo/microbiologia , Neoplasias do Timo/veterinária
10.
J Med Ultrason (2001) ; 45(3): 469-477, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29256187

RESUMO

OBJECTIVE: To measure the depth (D p) and diameter (D m) of the internal jugular vein (IJV), femoral vein (FV), and femoral artery (FA) in pediatric patients to evaluate the clinical implications. METHODS: This study included 125 pediatric patients. All of them underwent bilateral ultrasound study of vessels and were classified into three groups based on anthropometric and demographic parameters. RESULTS: Measured mean D p values were: 0.72 (0.34) cm for the FA, 0.79 (0.35) cm for the FV, and 0.77 (0.24) cm for the IJV. Mean antero-posterior D m values were: 0.37 (0.17) cm for the FA, 0.42 (0.22) cm for the FV, and 0.59 (0.23) cm for the IJV. D p and D m increased with age (A), weight (W), height (H), and body surface area (BSA). In the lower ranges of these variables, D p was similar for all three studied vessels (0.6-0.7 cm). In the higher ranges, femoral vessel D p values (1.1-1.2 cm) were larger than jugular ones (0.9 cm). Additionally, in these low ranges, IJV D m values were larger than femoral ones (0.45-0.50 vs. 0.25 cm). In the higher ranges, diameter values were similar (0.6-0.7 cm). CONCLUSIONS: In pediatric patients, major vessels can be located and their depth and diameter measured by vascular ultrasound. In younger patients, jugular and femoral vessels had similar depth values; in older ones, they had similar diameters. Ultrasound measurements in pediatric patients could facilitate the choice of the vessel to be cannulated, the catheter diameter, and the length of the needle to be used. Vascular canalization of IJV may be recommended as the first choice because of its low depth and large diameter.


Assuntos
Veia Femoral/anatomia & histologia , Veia Femoral/diagnóstico por imagem , Veias Jugulares/anatomia & histologia , Veias Jugulares/diagnóstico por imagem , Ultrassonografia , Adolescente , Fatores Etários , Estatura , Superfície Corporal , Peso Corporal , Criança , Pré-Escolar , Feminino , Veia Femoral/crescimento & desenvolvimento , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Pediátrica , Veias Jugulares/crescimento & desenvolvimento , Masculino , Tamanho do Órgão , Estudos Prospectivos
11.
Orthop Traumatol Surg Res ; 103(8): 1229-1234, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28987529

RESUMO

INTRODUCTION: Whiplash associated disorders are currently a common musculoskeletal problem. Besides the high incidence in western countries, the costs derived from prolonged treatment and medicolegal compensation, make this entity a challenging problem for clinicians and insurance companies. To date, no conservative treatment has shown clear superiority in the management of acute cases. HYPOTHESIS: Percutaneous needle electrolysis (PNE) is an effective approach for the treatment of Quebec type II acute whiplash syndrome (AWS). PNE consists in the application of brief galvanic currents into a damaged structure, producing a local controlled inflammatory response, with subsequent tissular healing enhancement. MATERIALS AND METHODS: One hundred AWS patients were randomized into: (a) standard physiotherapy intervention for AWS; (b) a standardized PNE protocol for AWS. Both groups were assessed for treatment outcome at the 5th week mark. RESULTS: Both groups showed a statistically significant improvement according to the Northwick Park Neck Questionnaire, visual analogic scale and pressure pain threshold. The improvement was similar in both groups, except for the pain pressure threshold, with a 56.6% reduction vs. 44.4% reduction in favour of the PNE group (P=0.035). In addition, the physio group consumed a mean treatment time of 20hours, while the PNE intervention averaged less than 1 hour in total. DISCUSSION: PNE can be considered as an effective treatment option for AWS. Importantly, the technique is highly cost-effective, with limited equipment required and a notable treatment time reduction, compared to more comprehensive physiotherapy protocols. TYPE OF STUDY: Randomized controlled trial. LEVEL OF PROOF: 1b.


Assuntos
Terapia por Estimulação Elétrica , Traumatismos em Chicotada/terapia , Adulto , Tratamento Conservador , Feminino , Humanos , Masculino , Limiar da Dor , Estudos Prospectivos , Ultrassonografia de Intervenção , Escala Visual Analógica , Traumatismos em Chicotada/classificação
12.
J Ultrasound ; 20(4): 285-292, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29204232

RESUMO

OBJECTIVES: To estimate, on the basis of anthropometric and demographic variables, the depth (Dp) and diameter (Dm) of femoral and jugular vessels, which have been located and measured by ultrasound, in pediatric patients. METHOD: 750 measurements of Dp and Dm of the femoral vein (FV), femoral artery (FA) and internal jugular vein (IJV) were made in 125 pediatric patients. The values were correlated with patients' sex, weight, age, size and body surface area (BSA). RESULTS: Mean Dp values were 0.72 (0.34) cm for FA, 0.79 (0.35) cm for FV and 0.77 (0.24) cm for IJV. Mean antero-posterior Dm values were 0.37 (0.17) cm for FA, 0.42 (0.22) cm for FV and 0.59 (0.23) cm for IJV. In the studied pediatric patients, femoral and jugular vessels depth correlated with age, size, weight and BSA (R = 0.46-0.60); vascular depth could be estimated from patients' weight and size (FA-Dp: R = 0.71; FV-Dp: R = 0.72; IJV-Dp: R = 0.53). Correlation with diameter was better for FA and FV (R = 0.81-0.89) than for IJV (R = 0.42-0.51); vascular diameter could be estimated from patient's size (FA-Dm: R = 0.89; FV-Dm: R = 0.86; IJV-Dm: R = 0.52). CONCLUSIONS: FV, FA and IJV depth and diameter correlated with weight, size, age and body surface area in the studied pediatric patients. Correlation was better for femoral than for jugular vessels. Depth could be estimated from patients' weight and size, while diameter could be estimated from the size. Such estimations may facilitate the choice of vessels to be cannulated, length and diameter of cannulation needles and the diameter of catheters to be used in pediatric patients.


Assuntos
Veia Femoral/diagnóstico por imagem , Veias Jugulares/diagnóstico por imagem , Ultrassonografia , Adolescente , Fatores Etários , Tamanho Corporal , Superfície Corporal , Criança , Pré-Escolar , Feminino , Veia Femoral/anatomia & histologia , Humanos , Lactente , Recém-Nascido , Veias Jugulares/anatomia & histologia , Modelos Lineares , Masculino , Tamanho do Órgão , Estudos Prospectivos , Caracteres Sexuais
13.
J Natl Cancer Inst ; 57(4): 875-82, 1976 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-63563

RESUMO

The major internal polypeptide of the bovine leukemia virus (BLV) was purified to homogeneity with the use of gel filtration and affinity chromatography. Like previous results, the protein had a molecular weight of 25,000 daltons as determined by electrophoresis in polyacrylamide gels with sodium dodecyl sulfate. More than 90% of the 125I-labeled protein was precipitated by bovine sera that reacted in immunofluorescence tests with acetone-fixed BLV-infected cells. In contrast, minimal precipitation (less than 5%) was observed with sera from 36 cattle in leukemia-free herds; these sera, negative by immunofluorescence, included six samples that had high titers of antibodies to the foamy-like bovine syncytia virus (BSV). Antisera prepared against several other oncornaviruses or the Mason-Pfizer monkey virus (M-PMV) did not bind the BLV p25 protein. Conversely, the labeled p30 polypeptides of several oncornaviruses tested did not react with bovine sera that had high titers of antibodies to BLV p25. Competitive radioimmunoassay(s) (RIA) also failed to detect cross-reactions between BLV p25 protein and the internal polypeptides of other mammalian and avian oncornaviruses, M-PMV, or foamy-like BSV. The RIA for BLV p25 antigen was also highly sensitive and specific for the detection and quantitation of the antigen in virus preparations and cell homogenates.


Assuntos
Antígenos Virais/análise , Vírus da Leucemia Bovina/imunologia , Retroviridae/imunologia , Animais , Ligação Competitiva , Bovinos , Linhagem Celular , Epitopos , Peso Molecular , Radioimunoensaio , Proteínas Virais/análise , Proteínas Virais/imunologia
14.
J Natl Cancer Inst ; 67(5): 1157-63, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6170771

RESUMO

Newborn sheep inoculated with phytohemagglutinin (PHA)-treated short-term, cultures of lymphocytes from cattle infected with bovine leukemia virus (BLV) or with a BLV- infected long-term culture of bovine leukemic lymphocytes became persistently infected with BLV. Fifty percent or more of the sheep died with histologically confirmed lymphosarcomas. Cytogenetic studies of representative cases demonstrated that the tumors did not result from the progressive growth of neoplastic lymphocytes in the inoculum but rather from the neoplastic transformation of the recipients lymphoid cells. Neither BLV infection nor lymphosarcoma was observed in control uninoculated sheep or in sheep given injections of PHA-treated cultures of lymphocytes from BLV-free cows. The virus recovered from the tumorous sheep was indistinguishable from BLV morphologically, antigenically, and biologically, and its reverse transcriptase had the same cation preference and immunologic properties as the BLV enzyme. Persistent BLV infection and lymphosarcoma were also observed in a group of sheep inoculated neonatally with BLV-containing cell-free culture supernatants. These results extend previous observations on the high susceptibility of sheep to BLV infection and provide definitive evidence that BLV is a tumor-inducing virus.


Assuntos
Vírus da Leucemia Bovina , Linfoma não Hodgkin/etiologia , Retroviridae , Infecções Tumorais por Vírus , Animais , Animais Recém-Nascidos , Transformação Celular Neoplásica , Feminino , Vírus da Leucemia Bovina/isolamento & purificação , Leucemia Experimental/etiologia , Leucemia Experimental/microbiologia , Leucemia Experimental/patologia , Linfoma não Hodgkin/microbiologia , Linfoma não Hodgkin/patologia , DNA Polimerase Dirigida por RNA/análise , Retroviridae/isolamento & purificação , Ovinos , Proteínas Virais/análise
15.
Cancer Res ; 36(11 Pt 1): 4152-9, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-61801

RESUMO

This study demonstrates that the bovine leukemia virus (BLV) can infect in vitro cells of human, simian, bovine, canine, caprine, ovine, and bat origin. Cultures of these cells, cocultivated with BLV-infected cells or inoculated with cell-free BLV preparations, continuoously showed the presence of cells with the internal BLV antigen as well as BLV-induced syncytia. Virus replication was abundant and increased with passage in bat lung cells and was moderate but constant in fetal canine thymus cells. The amounts of virus released by the simian DBS-FRhL-1 and caprine S-743 cultures were low to moderate during the first 4 to 8 weeks and decreased thereafter. In the infected fetal lamb spleen cell cultures, virus production was low and declined further with passage. Bovine embryonic spleen and human diploid embryonic lung WI-38 cell cultures produced very small amounts of virus only during the first two passages after inoculation despite the fact that they remained infected, as determined by the continuous presence of cell BLV antigen and syncytia. Morphologically and antigenically, the virus particles released by the monolayer cell cultures were indistinguishable from those found in short-term and long-term cultures of BLV-infected bovine lymphoid cells. Repeated electron microscopic examinations and serological tests showed that all the BLV-infected cultures, including those from which the infecting inocula were obtained, were free of the foamy-like bovine syncytial virus, parainfluenza 3 virus, infectious bovine rhinotracheitis virus, bovine viral diarrhea virus, and the maedi-like bovine R-29 virus.


Assuntos
Vírus da Leucemia Bovina/crescimento & desenvolvimento , Retroviridae/crescimento & desenvolvimento , Cultura de Vírus , Animais , Antígenos Virais , Bovinos , Células Cultivadas , Quirópteros , Cromossomos/análise , Cães , Imunofluorescência , Cabras , Humanos , Técnicas In Vitro , Vírus da Leucemia Bovina/enzimologia , Vírus da Leucemia Bovina/imunologia , Vírus da Leucemia Bovina/ultraestrutura , Macaca mulatta , Microscopia Eletrônica , Pan troglodytes , DNA Polimerase Dirigida por RNA/metabolismo , Ovinos , Cultura de Vírus/métodos , Replicação Viral
16.
Cancer Res ; 41(12 Pt 1): 4906-9, 1981 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6272983

RESUMO

The role of colostrum and milk in the transmission of the bovine leukemia virus (BLV) was examined by monitoring the development of BLV infection in calves that were fed since birth on colostrum and milk from their BLV-positive dams and then reared in complete or partial isolation from infected cattle. Twenty-one of the 25 calves raised in complete isolation remained negative for BLV until the last evaluation. At this time, 14 calves were older than 28 months of age, and seven were 16 to 20 months old. Three calves in this group became BLV positive before the age of five months, and one became so at the age of 12 months. Of the 16 calves raised in partial isolation, two were positive at the ages of 11 and 18 months, respectively. The other 14 calves remained negative during the 26 to 29 months of observation. It is not known if the six animals that became BLV positive in these two groups were infected by milk, or prenatally, or during contact with their infected dams. While only six of the 41 calves raised in isolation became infected, all 18 calves raised in contact with BLV-positive cows became infected before the age of 26 to 29 months of age, and 12 were positive at 16 to 20 months of age. Thus, it is apparent that, under natural conditions, milk-borne transmission of BLV, if it occurs at all, is much less frequent than contact transmission, despite the fact that, as shown in previous studies, infectious BLV is present in the colostrum and milk of most BLV-positive cows. Passively acquired maternal antibodies to BLV were probably responsible for the resistance of the calves to milk-borne infection.


Assuntos
Doenças dos Bovinos/transmissão , Colostro/microbiologia , Vírus da Leucemia Bovina , Leucemia/transmissão , Leite/microbiologia , Retroviridae , Animais , Bovinos
17.
Cancer Res ; 36(3): 1056-67, 1976 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-175949

RESUMO

Bovine buffy coat cells infected with the bovine leukemia virus (BLV) induce syncytia formation in human diploid embryonic lung cells as well as in monolayer cell cultures of bovine, simian, ovine, bat, and caprine origin, but not in mouse fibroblast cells, normall rat kidney cells, or RSV-transformed rat cells. Syncytia were not observed in diploid embryonic lung cells inoculated with bovine buffy coat cells free of BLV. The syncytia-induction effect is associated with the synthesis of complete BLV by the buffy coat cells and is independent of whether these cells are viable, disrupted, normal, or malignant. Cell-free preparations of BLV and density gradient-purified virus also induce syncytia when added directly to diploid embryonic lung cells and to bovine, bat, and caprine monolayer cell cultures. Ether treatment, ultraviolet light irradiation, heating, freezing, and thawing destroy the syncytia-inducing activity of BLV. This activity is also neutralized when the virus is incubated with sera containing antibodies to BLV, but not when incubated with sera free of these antibodies or reference serum for the foamy-like bovine syncytial virus. Several other lines of evidence rule out the possibility that this virus or other bovine viruses are responsible for the syncytia-inducing phenomenon described here. BLV antigen was consistently detected by the immunofluorescent test in the syncytia-positive monolayer indicator cultures. However, syncytia formation was not necessarily associated with BLV production by the indicator cells. The ability to induce syncytia in monolayer cultures of nontransformed cells distinguishes BLV from all the known C-type luekemia viruses.


Assuntos
Efeito Citopatogênico Viral , Vírus da Leucemia Bovina , Retroviridae , Anticorpos Antivirais , Antígenos Virais/análise , Sistema Livre de Células , Éter/farmacologia , Congelamento , Temperatura Alta , Vírus da Leucemia Bovina/imunologia , Vírus da Leucemia Bovina/efeitos da radiação , Retroviridae/imunologia , Raios Ultravioleta , Replicação Viral
18.
Cancer Res ; 36(3): 1068-73, 1976 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-175950

RESUMO

The ability of the bovine C-type leukemia virus to induce syncytia formation in monolayer cell cultures has been used to develop a specific and simple infectivity assay for the virus. Using bovine embryonic spleen cells or human diploid embryonic lung cells as indicator cells, the results of the assay can be evaluated in 4 to 6 or 6 to 8 days, respectively. Pretreatment of the indicator cells with DEAE-dextran greatly increases the sensitivity of the assay. The assay is quantitative and can be applied as a direct method for the identification of bovine C-type leukemia virus-infected animals; it also provides a simple, and sensitive procedure for the detection and titration of virus-neutralizing antibodies.


Assuntos
Efeito Citopatogênico Viral , Vírus da Leucemia Bovina/isolamento & purificação , Retroviridae/isolamento & purificação , Anticorpos Antivirais/análise , Células Cultivadas , Vírus da Leucemia Bovina/imunologia , Testes de Neutralização
19.
Cancer Res ; 39(10): 3952-4, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-225012

RESUMO

This report describes the development of a 7-day infectivity assay for bovine leukemia virus (BLV) which is based on the induction of the major internal virion antigen (a protein with a molecular weight of 25,000) in susceptible indicator monolayer cell cultures. In this assay, the antigen is detected in the indicator cells by the immunoperoxidase antibody technique using a specific rabbit antiserum to a BLV protein with a molecular weight of 25,000. The immunoperoxidase infectivity assay is specific, quantitative, reproducible, and more sensitive than the previously described syncytia induction assay. The immunoperoxidase infectivity assay can be applied to the detection of BLV-infected cells and provides a reliable method for the direct diagnosis of BLV infection in cattle.


Assuntos
Antígenos Virais , Transformação Celular Neoplásica , Técnicas Imunoenzimáticas , Vírus da Leucemia Bovina/isolamento & purificação , Retroviridae/isolamento & purificação , Animais , Anticorpos Antivirais , Especificidade de Anticorpos , Bovinos , Células Cultivadas , Vírus da Leucemia Bovina/imunologia , Métodos
20.
Cancer Res ; 36(4): 1251-7, 1976 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-56993

RESUMO

By means of gel filtration and isoelectric focusing, an antigen of the bovine C-type leukemia virus was isolated in a highly purified form from extracts of infected cells. The antigen has a molecular weight of approximately 25,000 daltons and an isoelectric point of 6.4 to 6.6. In immunodiffusion experiments, the antigen forms a line of identity with an antigen extracted from highly purified bovine C-type leukemia virus by treatment with ether or Triton X-100. As determined by immunodiffusion analyses, the bovine C-type leukemia virus antigen does not have antigenic determinants in common with the murine or feline leukemia viruses, the foamy-like bovine syncytia virus, or the Mason Pfizer monkey virus.


Assuntos
Antígenos Virais/isolamento & purificação , Vírus da Leucemia Bovina/imunologia , Retroviridae/imunologia , Células Cultivadas , Cromatografia em Gel , Reações Cruzadas , Epitopos , Imunodifusão , Focalização Isoelétrica , Marcação por Isótopo , Vírus da Leucemia Felina/imunologia , Peso Molecular , Vírus Oncogênicos/imunologia , Proteínas Virais/análise
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