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1.
Animals (Basel) ; 14(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38672399

RESUMO

The objective of this dairy farm study was to investigate the preweaning health, performance, immunity, and enteric pathogen shedding in calves supplemented with colostrum during five days after birth compared to calves not supplemented with colostrum. The colostrum supplementation was the previously frozen colostrum added to the milk replacer from day 2-5 given to 39 calves, and 36 Control calves received a milk-derived supplement. There was no significant difference in preweaning weight gain between the treatment groups. Serum samples collected on days 2, 7, 14, and 21 indicated that total and antigen-specific IgG levels against rotavirus, coronavirus, and E. coli F5 were not significantly different between the treatment groups. Fecal samples taken on days 7, 14, and 21 were all negative for coronavirus and E. coli F5, whereas there were low levels of Cryptosporidia and a trend for low levels of rotavirus on day 14 in colostrum-supplemented compared to Control calves. Respiratory clinical signs, depressed attitude and body temperature tended to be reduced in colostrum-supplemented compared to Control calves. This study shows that, even in calves with good colostrum status and high plane of nutrition, there can be benefits of post-closure colostrum supplementation including reduced Cryptosporidia and rotavirus shedding and reduced respiratory disease.

2.
J Dairy Sci ; 107(6): 3836-3846, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38135039

RESUMO

Respiratory tract infections remain a major problem during calf rearing, especially among milk (formula)-fed veal. Preconditioning of calves through appropriate colostrum management and vaccination could be helpful to address this issue. The objective of this study was to investigate whether the presence of serum antibodies against major respiratory tract pathogens (bovine respiratory syncytial virus, parainfluenza 3 virus, bovine coronavirus, Mycoplasmopsis bovis, Histophilus somni, Pasteurella multocida, and Mannheimia haemolytica) and total serum IgG concentration in calves upon arrival at the veal facility were associated with the occurrence of clinical bovine respiratory disease (BRD) or lung consolidation in the first 3 wk, as assessed by both the Wisconsin BRD scorecard (based on 5 clinical signs: cough, rectal temperature, ear position, and nasal and ocular discharge) and by quick thoracic ultrasound scanning. Additionally, the association between calves' serostatus production parameters were explored. A prospective cohort study was conducted among 442 male dairy calves on a large veal calf facility in Belgium. Both clinical scoring and quick thoracic ultrasound scanning were performed on all calves at 4 key moments in the production cycle: arrival at the facility, initiation of first metaphylactic antimicrobial treatment at peak incidence of BRD (wk 1), end of the first metaphylactic treatment (short-term evaluation) and at wk 10 (long-term evaluation). Mixed effects logit regression models were fitted to quantify relationships. The outcomes of interest were clinical respiratory disease (Wisconsin BRD scorecard positive), lung consolidation (≥1 cm or ≥ 3 cm), average daily weight gain, and cold carcass weight. In the first week of production, incidence of lung consolidation (≥1 cm) quickly increased from 14.9% upon arrival to 43.0% at the peak of the BRD incidence, while clinical BRD increased from 3.6% to 16.1%. The main finding of this study was that calves who were seropositive for bovine respiratory syncytial virus and bovine coronavirus at arrival had reduced odds of developing lung consolidation at the peak of the outbreak, 0.58 odds ratio (95% CI: 0.38-0.89) and 0.37 odds ratio (95% CI: 0.20-0.69), respectively. No relationships between serum IgG concentration at arrival and the development of lung consolidations or clinical respiratory disease were found. Nevertheless, on average, throughout the first 10 wk of the fattening cycle, calves with failed transfer of passive immunity (serum IgG < 7.5 g/L) gained 40 g/d (95% CI: 10-70 g/d) less weight (average daily gain). Hence, ensuring that calves have a positive serostatus for these respiratory tract pathogens before entering the facility may help lower the incidence of lung consolidations, subsequently reducing treatment incidence and the adverse effects on primary economic outcomes.


Assuntos
Doenças dos Bovinos , Animais , Bovinos , Vírus Sincicial Respiratório Bovino , Masculino , Estudos Prospectivos , Doenças Respiratórias/veterinária , Infecções Respiratórias/veterinária , Coronavirus Bovino
3.
Front Vet Sci ; 10: 1192598, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37538168

RESUMO

Effective clinical communication is essential for bovine veterinary practitioners to establish and maintain positive client relationships. When applied properly in herd health consultancy, it increases client satisfaction and adherence to veterinary advice, and improves patient health and welfare. Although communication skills are often taught by providing feedback on simulated conversations, this has limitations, including time constraints, subjective assessments, and cost. The Veterinary DialogueTrainer (VDT) is an online serious game platform using 'digital role-play' with avatars, recently developed to enhance and assess learning outcomes, improve use of learned skills, and increase cost-effectiveness of communication training. The objective was to evaluate its suitability and applicability. Finnish (n = 24) and Swedish (n = 21) bovine veterinarians participated in communication training using VDT for training and assessment. Participants completed the provided scenario at least twice. After playing a bovine health communication simulation, participants received their scores and feedback on selected conversation options. VDT scores measured multiple aspects of communication on a 0-100% scale, based on motivational interviewing methodology and Calgary-Cambridge guidelines. Mean (±SD) number of attempts participants played the scenario was 4.1 (±2.6, Finland) and 3.9 (±1.3, Sweden), with highest total score reached after a mean of 3.5 (±2.1, Finland) and 3.1 (±1.1, Sweden) attempts. On the first attempt, 39 participants (87%) scored <50% of the highest possible score, whereas most (n = 34, 76%) achieved a higher score on the second attempt. Mean total score increased from 15 (±14) to 77% (±33) for Finish participants and from 40 (±22.0) to 87% (±19.4) for Swedish participants. The majority (n = 33, 73%) of participants reached a score >80% after 4.0 (±1.6, Finland) or 2.8 (±1.0, Sweden) attempts. Net Promoter Score of the training was +89 (Finland), +88 (Finland) and + 83 (Sweden) on a scale from -100 to +100, indicating that most participants were very likely to recommend the training to other veterinarians. Use of VDT increased communication skills scores but whether it will improve communication skills in practice requires further study. We concluded there is a likely benefit of using the VDT in teaching and monitoring veterinary communication competencies and preparing for offline role-plays and real-life conversations in veterinary practice.

4.
J Dairy Sci ; 106(12): 9260-9275, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37641351

RESUMO

The high degree of commingling and accumulation of stressors during and after transport makes prevention of bovine respiratory disease (BRD) extremely challenging in the veal and dairy beef industry. Upon arrival, vaccination for agents involved in BRD is practically most achievable, but its efficacy under such conditions in dairy veal calves is unknown. Given the high prevalence of subclinical pneumonia in these settings, the primary objective of the present study was to determine the effect of 2 vaccination protocols administered upon arrival against bovine respiratory syncytial virus (BRSV), bovine parainfluenza type 3 virus (BPI-3), and Mannheimia haemolytica on clinical BRD and lung ultrasonographic findings in dairy veal calves. In addition, the effects of vaccination on average daily live weight gain and cold carcass weight were determined. In this randomized clinical trial, 443 male dairy calves were assigned to one of 3 groups: a negative, placebo-controlled group (n = 151), a vaccination group with 2 subcutaneous injections 4 wk apart with an inactivated vaccine containing BRSV, BPI-3, and M. haemolytica (parenteral [PE] group; n = 149) and a second vaccination group receiving an intranasal live-attenuated vaccine containing BRSV and BPI-3 and 2 subcutaneous vaccinations with the same inactivated vaccine as the PE vaccination group (intranasal-parenteral [IN-PE] group; n = 143). Clinical scoring and quick thoracic ultrasonography (qTUS) were performed on all calves on arrival (wk 0), at the peak of respiratory disease (outbreak; wk 1), at the end of the first antimicrobial group treatment (wk 3), and at a long-term evaluation point (wk 10). Culture and nanopore sequencing on nonendoscopic bronchoalveolar lavage (nBAL) samples were used to identify pathogens involved in the outbreak. Upon arrival, 15.1% of the calves had lung consolidation ≥1cm and incidence quickly rose to 42.8% during the outbreak. In both the PE and IN-PE group, the odds of pneumonia in wk 10 were reduced by 62% (odds ratio [OR] = 0.38; 95% confidence interval [CI] = 0.23-0.64) and 41% (OR = 0.59; 95% CI = 0.37-0.96), respectively. Short-term cure rate (50.3%), as determined immediately after the first group antimicrobial treatment, was not influenced by vaccination. In contrast, long-term cure rate, determined at wk 10, was affected by vaccination with higher cure in the PE group compared with the control group (69.4% vs. 51.2%; OR = 2.2; 95% CI = 1.1-5.0). Average daily gain in the first 10 wk of production was not affected by vaccination. Vaccination resulted in an increase in cold carcass weight of 3.5 and 4.3 kg in the PE (95% CI = -0.9-7.9) and IN-PE group (95% CI = -0.17-8.7), respectively. In conclusion, under the conditions of the present study, vaccination upon arrival resulted in a reduced prevalence of pneumonia at wk 10 of production, likely caused both by an improved cure rate of secondary infections and a reduced incidence of new cases between outbreak and long-term evaluation. The present protocol, using qTUS for pneumonia detection and nBAL diagnostics for pathogen identification adds a new dimension to randomized clinical trials on respiratory disease in calves.


Assuntos
Anti-Infecciosos , Doenças dos Bovinos , Pneumonia , Vírus Sincicial Respiratório Bovino , Animais , Bovinos , Masculino , Doenças dos Bovinos/diagnóstico por imagem , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/epidemiologia , Vacinação/veterinária , Pneumonia/veterinária , Ultrassonografia/veterinária , Vacinas de Produtos Inativados
5.
Vaccines (Basel) ; 10(1)2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35062765

RESUMO

Bovine parainfluenza type 3 (BPIV3) and bovine respiratory syncytial virus (BRSV) may cause bovine respiratory disease (BRD) in very young calves, and therefore vaccination should induce protection at the youngest age and as quickly as possible. This can be achieved by intranasal vaccination with a vaccine containing live attenuated BRSV and BPIV3 virus strains. The objective of this study was to measure gene expression levels by means of RT-qPCR of proteins involved in the innate and adaptive immune response in the nasopharyngeal mucosae after administration of the above-mentioned vaccine and after challenge with BPIV3. Gene expression profiles were different between (i) vaccinated, (ii) nonvaccinated-challenged, and (iii) vaccinated-challenged animals. In nonvaccinated-challenged animals, expression of genes involved in development of disease symptoms and pathology were increased, however, this was not the case after vaccination. Moreover, gene expression patterns of vaccinated animals reflected induction of the antiviral and innate immune pathways as well as an initial Th1 (cytotoxic) cellular response. After challenge with BPIV3, the vaccinated animals were protected against nasal shedding of the challenge virus and clinical symptoms, and in parallel the expression levels of the investigated genes had returned to values that were found before vaccination. In conclusion, in comparison to the virulent wild-type field isolates, the two virus strains in the vaccine have lost their capacity to evade the immune response, resulting in the induction of an antiviral state followed by a very early activation of innate immune and antiviral responses as well as induction of specific cellular immune pathways, resulting in protection. The exact changes in the genomes of these vaccine strains leading to attenuation have not been identified. These data represent the real-life situation and can serve as a basis for further detailed research. This is the first report describing the effects on immune gene expression profiles in the nasal mucosae induced by intranasal vaccination with a bivalent, live BRSV-BPI3V vaccine formulation in comparison to wild-type infection with a virulent BPI3V strain.

6.
Animals (Basel) ; 11(5)2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33923017

RESUMO

Neonatal calf diarrhoea (NCD) is a major health challenge with a negative impact on farm profitability, calf welfare and antimicrobial use. Neonatal calves are particularly sensitive to enteric infections. Thus, a key point for prevention is minimising infectious pressure and maximising specific immune responses. An amount of 120 dams not previously vaccinated against NCD were randomly allocated to one of three study groups: negative control versus two vaccinated groups (A and B). In the control group, the average level of antibodies was significantly low for both BoCV and ETEC (15.6 and 13.9% in the colostrum samples, respectively), demonstrating the importance of dam vaccination. Indeed, the level of specific immunity was significantly increased for BoCV and ETEC with dam vaccination using both one-shot vaccines versus the control group. Moreover, the statistical analysis revealed a significantly higher level of antibodies for BoCV and ETEC in colostrum samples in vaccine A versus vaccine B and the control group. In accordance, the calf serum demonstrated a significantly higher level and greater homogeneity of antibodies against BoCV and ETEC in the Vaccine A group versus other experimental groups (p < 0.05). In conclusion, this study demonstrated a different specific immune response for the pathogens depending on the vaccine used to control NCD in cows.

7.
Vet Immunol Immunopathol ; 230: 110130, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33068827

RESUMO

Almost all bovine intranasal respiratory vaccines require a spraying device, but there are no published reports which prove the necessity of this. The objective of this investigation was to compare the efficacy of the Bovilis® INtranasal RSP™ Live vaccine when applied with or without an (intra)nasal spraying device. This vaccine contains live, attenuated strains of bovine respiratory syncytial virus (BRSV) and bovine parainfluenza virus type 3 (BPI3V) and is licensed to protect young cattle against respiratory infections with wild-type field isolates of these viruses. Two efficacy studies, for BRSV and BPI3V respectively, were performed in which the vaccine was administered using a spraying device or directly from the tip of a syringe as a liquid stream. Both BRSV-vaccinated groups showed a reduction of nasal shedding, BRSV titres in lung washings and clinical symptoms. The BPI3V vaccinated groups showed a significant reduction of nasal shedding and a non-significant reduction of clinical symptoms. Overall, in both studies, the groups in which vaccine was administered without the spraying device performed better than the groups with the spraying device, although this difference was not statistically significant. In conclusion, a spraying device to administer Bovilis® INtranasal RSP™ Live was not required and both application methods induced a protective immune response. This makes application more convenient and flexible for future users and animals.


Assuntos
Administração Intranasal/instrumentação , Administração Intranasal/veterinária , Infecções Respiratórias/prevenção & controle , Infecções Respiratórias/veterinária , Vacinação/métodos , Vacinação/veterinária , Vacinas Virais/administração & dosagem , Aerossóis/administração & dosagem , Fatores Etários , Animais , Anticorpos Antivirais/sangue , Bovinos , Doenças dos Bovinos/prevenção & controle , Sprays Nasais , Vírus da Parainfluenza 3 Bovina/imunologia , Vírus Sincicial Respiratório Bovino/imunologia , Vacinação/instrumentação , Vacinação/normas , Vacinas Atenuadas/administração & dosagem
8.
Res Vet Sci ; 124: 10-12, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30776549

RESUMO

The objective of this study was to assess the prevalence of three serotypes, A1, A2, and A6 in 98 M. haemolytica isolates collected from clinical BRD cases in European cattle and assess their antimicrobial resistance profiles. Isolates were characterized by serotyping (plate agglutination and serotype specific PCR) and antimicrobial susceptibility testing. The study identified a predominance of serotypes A1 (59%) and A6 (22%) in European M. haemolytica isolates exhibiting a relatively low level of antimicrobial resistance. A comprehensive understanding of the relative prevalence of different M. haemolytica serotypes in Europe informs a targeted approach for vaccine design against BRD.


Assuntos
Complexo Respiratório Bovino/epidemiologia , Farmacorresistência Bacteriana/imunologia , Mannheimia haemolytica/efeitos dos fármacos , Infecções por Pasteurellaceae/veterinária , Sorotipagem/veterinária , Animais , Antibacterianos/farmacologia , Complexo Respiratório Bovino/microbiologia , Bovinos , Europa (Continente)/epidemiologia , Mannheimia haemolytica/fisiologia , Infecções por Pasteurellaceae/epidemiologia , Infecções por Pasteurellaceae/microbiologia , Prevalência
9.
J Dairy Sci ; 97(4): 2145-54, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24534510

RESUMO

The aim of this study was to determine the prevalence, major management systems, and fresh cow clinical conditions associated with ketosis in western European dairy herds. A total of 131 dairies were enrolled in Germany, France, Italy, the Netherlands, and the United Kingdom during 2011 to 2012. A milk-based test for ketones (Keto-Test; Sanwa Kagaku Kenkyusho Co. Ltd., Nagoya, Japan; distributed by Elanco Animal Health, Antwerp, Belgium) was used for screening cows between d 7 and 21 after calving and ketosis was defined as a Keto-Test ≥100µmol/L. Study cows were observed for clinical disease up to 35d postcalving. Multivariate analysis (generalized estimating equation logistic regression) was performed to determine country, farm, management, feed, and cow factors associated with ketosis and to determine associations between ketosis and fresh cow diseases. Thirty-nine percent of the cows were classified as having ketosis. The herd average of ketosis was 43% in Germany, 53% in France, 31% in Italy, 46% in the Netherlands, and 31% in the United Kingdom. Of the 131 farms, 112 (85%) had 25% or more of their fresh cows resulting as positive for ketosis. Clinical ketosis was not reported in most farms and the highest level of clinical ketosis reported was 23%. The risks of ketosis were significantly lower in Italy and the United Kingdom compared with France, the Netherlands, and Germany. Larger herd size was associated with a decreased risk of ketosis. The farms that fed partially mixed rations had 1.5 times higher odds of ketosis than those that fed total mixed rations. Cows that calved in April to June had the highest odds of ketosis, with about twice as high odds compared with cows that calved in July to September. The cows that calved in January to March tended to have 1.5 times higher risk of ketosis compared with cows that calved in July to September. The odds of ketosis in parity 2 and parity 3 to 7 was significantly higher (1.5 and 2.8 times higher, respectively) than the odds of ketosis in parity 1. The odds of ketosis was significantly smaller in parity 2 compared with parity 3 to 7. Ketosis was associated with significantly higher odds of all common fresh cow conditions: metritis, mastitis, displaced abomasum, clinical ketosis, lameness, and gastrointestinal disorders. Odds of ketosis in cows having had twins or dystocia were not increased, whereas higher odds of ketosis were observed in cows with milk fever or retained placenta.


Assuntos
Doenças dos Bovinos/epidemiologia , Cetose/veterinária , Mastite Bovina/epidemiologia , Paresia Puerperal/epidemiologia , Placenta Retida/veterinária , Abomaso/patologia , Animais , Bovinos , Indústria de Laticínios , Distocia/veterinária , Europa (Continente)/epidemiologia , Feminino , Abrigo para Animais , Cetose/epidemiologia , Modelos Logísticos , Paridade , Placenta Retida/epidemiologia , Gravidez , Prevalência , Transtornos Puerperais/veterinária
10.
J Biomater Appl ; 27(7): 828-39, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22090430

RESUMO

Pluronic® F127 is a biocompatible, injectable, and thermoresponsive polymer with promising biomedical applications. In this study, a chemically modified form, i.e., Pluronic ALA-L with tailored degradation rate, was tested as an encapsulation vehicle for osteoblastic cells. UV cross-linking of the modified polymer results in a stable hydrogel with a slower degradation rate. Toxicological screening showed no adverse effects of the modified Pluronic ALA-L on the cell viability. Moreover, high viability of embedded cells in the cross-linked Pluronic ALA-L was observed with life/death fluorescent staining during a 7-day-culture period. Cells were also cultured on macroporous, cross-linked gelatin microbeads, called CultiSpher-S® carriers, and encapsulated into the modified cross-linked hydrogel. Also, in this situation, good cell proliferation and migration could be observed in vitro. Preliminary in vivo tests have shown the formation of new bone starting from the injected pre-loaded CultiSpher-S® carriers.


Assuntos
Materiais Biocompatíveis/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Osteoblastos/citologia , Poloxâmero/química , Células 3T3 , Animais , Materiais Biocompatíveis/metabolismo , Proliferação de Células , Sobrevivência Celular , Células Imobilizadas/citologia , Cabras , Hidrogel de Polietilenoglicol-Dimetacrilato/metabolismo , Camundongos , Osteogênese , Poloxâmero/metabolismo
11.
J Vet Sci ; 13(4): 437-40, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23271188

RESUMO

Here, we describe two cases of left displaced abomasum (LDA) in Holstein cattle at 6 and 9 months of twin gestation. Clinical examination revealed signs of proximal ileus with marked abdominal distension, but no ping sounds. An unusually high position of the gravid uterine horn on the left side was bserved with ultrasound. Left exploratory laparotomy confirmed that the abomasum was displaced to the left and entrapped between the rumen and twin gravid uterine horn. A left surgical approach was necessary to correct the condition. Both animals recovered and gave birth to healthy twins. The present cases indicate that the subomental position of a heavy twin gravid uterine horn is a possible mechanical cause of LDA.


Assuntos
Abomaso/cirurgia , Doenças dos Bovinos/diagnóstico por imagem , Doenças dos Bovinos/cirurgia , Gravidez Múltipla , Gastropatias/veterinária , Abomaso/diagnóstico por imagem , Animais , Bovinos , Feminino , Gravidez , Rúmen/anatomia & histologia , Gastropatias/diagnóstico por imagem , Gastropatias/cirurgia , Ultrassonografia , Útero/anatomia & histologia
12.
Tissue Eng Part A ; 16(2): 617-27, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19743958

RESUMO

In situ forming bone substitute materials are attractive candidates for filling irregularly shaped defects. In this study, a chemically modified form of the Pluronic F127 hydrogel was used. Similar to the parent form, this derivative underwent a sol-gel transition in the body and additional radical curing resulted in a stable three-dimensional network gel with a controllable degradation rate. An extra cell source of autologous bone marrow-derived mesenchymal stem cells was mixed with the hydrogel to increase the ossification process, when implanted in noncritical size unicortical tibia defects. These cells were cultured and predifferentiated on two types of cell carrier systems, that is, gelatin CultiSpher-S microcarriers and hydroxyapatite tubular carriers. Radiographic and histological evaluation revealed that bone regeneration was comparable in the defects with the bone substitute compositions and the untreated control defects at 2 and 4 weeks postimplantation and that newly formed bone originated from the cells on the CultiSpher-S carriers. This resulted, 6 and 8 weeks postimplantation, in faster bone repair in the defects filled with the hydrogel plus CultiSpher-S carriers in comparison to the control defects. Surprisingly, there was no formation of new bone originating from the hydroxyapatite carriers. The hydrogel by itself seemed to stimulate the natural repair process.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Poloxâmero/farmacologia , Tíbia/patologia , Animais , Seguimentos , Cabras , Implantes Experimentais , Injeções , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Modelos Animais , Osteogênese/efeitos dos fármacos , Poloxâmero/química , Radiografia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Transplante Autólogo
13.
Tissue Eng Part A ; 15(7): 1501-11, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19072089

RESUMO

An in situ crosslinkable, biodegradable, methacrylate-endcapped poly(D,L-lactide-co-epsilon-caprolactone) in which crosslinkage is achieved by photoinitiators was developed for bone tissue regeneration. Different combinations of the polymer with bone marrow-derived mesenchymal stem cells (BMSCs) and alpha-tricalcium phosphate (alpha-TCP) were tested in a unicortical tibial defect model in eight goats. The polymers were randomly applied in one of three defects (6.0 mm diameter) using a fourth unfilled defect as control. Biocompatibility and bone-healing characteristics were evaluated by serial radiographies, histology, histomorphometry, and immunohistochemistry. The results demonstrated cell survival and proliferation in the polymer-substituted bone defects. The addition of alpha-TCP was associated with less expansion and growth of the BMSCs than other polymer composites.


Assuntos
Células-Tronco Mesenquimais/citologia , Metacrilatos/química , Modelos Biológicos , Poliésteres/química , Tíbia/patologia , Alicerces Teciduais/química , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/efeitos da radiação , Separação Celular , Células Cultivadas , Cabras , Imuno-Histoquímica , Injeções , Luz , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos da radiação , Metacrilatos/farmacologia , Poliésteres/farmacologia , Radiografia , Tíbia/diagnóstico por imagem , Tíbia/efeitos dos fármacos , Tíbia/cirurgia
14.
J Mater Sci Mater Med ; 19(7): 2761-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18305902

RESUMO

An in situ crosslinkable, biodegradable, methacrylate-encapped porous bone scaffold composed of D: ,L: -lactide, epsilon-caprolactone, 1,6-hexanediol and poly(ortho-esters), in which crosslinkage is achieved by photoinitiators, was developed for bone tissue regeneration. Three different polymer mixtures (pure polymer and 30% bioactive glass or alpha-tricalcium phosphate added) were tested in a uni-cortical tibial defect model in eight goats. The polymers were randomly applicated in one of four (6.0 mm diameter) defects leaving a fourth defect unfilled. Biocompatibility and bone healing properties were evaluated by serial radiographies, histology and histomorphometry. The pure polymer clearly showed excellent biocompatibility and moderate osteoconductive properties. The addition of alpha-TCP increased the latter characteristics. This product offers potentials as a carrier for bone healing promoter substances.


Assuntos
Substitutos Ósseos/administração & dosagem , Substitutos Ósseos/uso terapêutico , Modelos Animais de Doenças , Poliésteres/química , Fraturas da Tíbia/terapia , Animais , Substitutos Ósseos/química , Substitutos Ósseos/efeitos da radiação , Feminino , Cabras , Humanos , Injeções , Luz , Teste de Materiais , Fotoquímica/métodos , Fraturas da Tíbia/patologia , Resultado do Tratamento
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