Repairing Rabbit Radius Bone Defects with Simvastatin Compound Biological Bone

Objective: This study aimed to investigate the feasibility of repairing rabbit radius bone defects with simvastatin compound biological bone. Methods: Simvastatin biological bone material was prepared, and osteoblasts were cultured. A total of 42 New Zealand white rabbits were randomly divided into four groups, and a bone defect with a length of 15 mm was created at the middle part of the radial shaft of both limbs in each rabbit, thereby establishing a bone defect model. The grafts in group A were biological bones of osteoblasts combined with simvastatin; the grafts in group B were biological bones of simvastatin; the grafts in group C were biological compound bones of osteoblasts; and the grafts in group D were simple biological bones. In each group, four animals were randomly sacrificed at the sixth and twelfth week after surgery, and specimens were collected for gross observation, X-ray examination, histological observation, and biomechanical testing. In each group, two animals were randomly sacrificed at the twelfth week after surgery; a three-point bending test was performed using a biomechanical testing machine, and the results were compared with those of a normal radius. Results: The X-ray and histological examinations at 6 and 12 weeks after surgery revealed that the osteogenesis ability of the simvastatin biological bone and osteoblast-simvastatin biological bone was better than that of the osteoblast biological bone and simple biological bone, which was superior in group A and group B to group C and group D. The results of the biomechanical examination revealed that the maximum stress of the normal radius was significantly higher than that of the experimental groups. Among the experimental groups, the difference between group A and group B was not statistically significant, and the maximum stress was higher in groups A and B than in groups C and D. Conclusion: Simvastatin biological bone material can promote the repair of rabbit radius defects and increase the quality of bone healing.

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BMSCs Seeding in Different Scaffold Incorporation with Hyperbaric Oxygen Treat Seawater Immersed Bony Defect

10.21203/rs.3.rs-44123/v3 ◽

2021 ◽

Author(s):

gan zhang ◽

Xiaosong Chen ◽

Xunsheng Cheng ◽

Xiuwu Ma ◽

Congcong Chen

Keyword(s):

Bone Formation ◽

Bone Defect ◽

Medullary Canal ◽

Bony Defect ◽

New Bone Formation ◽

X Ray ◽

New Zealand White Rabbits ◽

Group A ◽

Group B ◽

Group D

Abstract Introduction: The experiment was undertaken to estimate the effect of BMSCs seeding in different scaffold incorporation with HBO on the repair of seawater immersed bone defect. And future compared n-HA/PLGA with β-TCP/PLGA as scaffold in treatment effect of seawater immersed bone defect.Methods: 60 New Zealand White rabbits with standard seawater defect in radius were randomly divided to group A (implant with nothing), group B (implanted with atuogenous bone), group C (implanted with n-HA/PLGA/BMSCs, and Group D ( implanted with β-TCP/PLGA/BMSCs). After implant, each rabbit receive HBO treatment at 2.4 ATA 100% oxygen for 120 minutes per day for 2 weeeks. Radiograph, histological and biomechanical examination were used to analyze osteogenesis.Result: X-ray analysis show that n-HA/PLGA/BMSCs and β-TCP/PLGA/BMSCs could accelerate the new bone formation, and the new bone formation in group C was lager than in group D or group A, and close to group B (P<0.05). After 12 weeks, in group A, defect without scaffold show a loose connect tissue filled in the areas. The medullary canal in group B was recanalizated. Defect in group C and D show a larger number of wove bone formation. The new wove bone formation in defect areas in group C was lager than D. The mechanical examination revealed ultimate strength at 12 weeks were group D>group C>group B>group A(P<0.05).Conclusion: Scaffold of n-HA/PLGA and β-TCP/PLGA incorporation with HBO and BMSCs were effective to treat seawater immersed bone defect, and n-HA/PLGA was more excellent than β-TCP/PLGA.

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Results of the Study of Bone Tissue Density in Patients of the Study Groups at the Restoration of Bone Defects by Various Osteoplastic Materials

Ukraïnsʹkij žurnal medicini bìologìï ta sportu ◽

10.26693/jmbs06.02.158 ◽

2021 ◽

Vol 6 (2) ◽

pp. 158-162

Author(s):

A. V. Bambuliak ◽

◽

N. B. Kuzniak ◽

R. R. Dmitrenko ◽

S. V. Tkachik ◽

...

Keyword(s):

Computed Tomography ◽

Bone Density ◽

Bone Tissue ◽

Bone Defect ◽

Maxillofacial Surgery ◽

Bone Defects ◽

X Ray ◽

Group A ◽

X Ray Computed ◽

Group B

The restoration processes of damaged or lost bone tissue are an important and topical issue of surgical dentistry and maxillofacial surgery today. According to statistics, diseases that are accompaning by destructive changes in bone tissue occupy one of the dominant places among the nosologies of MFA. Along with the use of updated methods of surgical technique, both before and now the problem of choice of bone-plastic material is relevant, because it is known that osteoplasty opens up great opportunities for complete rehabilitation of patients. The purpose of the study was to determine the effectiveness of our developed osteoplastic composition for the restoration of bone defects in dentistry. Materials and methods. X-ray computed tomography to determine bone density was performed in 26 patients with bone defect replacement "Kolapan-L" (group A), 28 people during augmentation of our proposed osteoplastic composition "Kolapan-L" + multipotent mesenchymal stromal cells + platelet-rich plasma) (group B), and 25 patients where the healing of the bone defect occurred spontaneously (group B). X-ray computed tomography was performed on a 16-slice spiral computed tomography Siemens Somatom Emotionc. Image processing was performed using the program "Dicom". Statistical processing of research results was carried out using conventional methods of variation statistics. Results and discussion. After 1 year of research, the average value of the bone density in patients of group B was probably higher: 1.5 times and 1.8 times relative to the corresponding data in groups A and B. At the same time, the minimum value of the bone density in patients of subgroups A and B was 1.5 times and 1.8 times lower than in persons of group B (p <0.01, p1 <0.01). At the same time, the maximum values of the bone density in patients of group B, where the augmentation of bone defects was performed using our proposed composition, were 1.4 times (p <0.01) and 1.8 times (p <0.05, p1 <0.01) higher than in group A, in the replacement of bone defects "Kolapan-L" and in group B, where the healing of the bone defect was spontaneous, respectively. It was found that in patients of group B after 12 months of studies, the average density of osteoregeneration was 1036.69±55.53 (HU), which was 1.5 times and 1.8 times more than in group A (p <0.01) and in group B patients (p <0.05, p1 <0.01) respectively. Conclusion. The use of tissue equivalent of bone tissue, proposed by us to replace a bone defect based on multipotent mesenchymal adipose tissue cells, contributed to the maximum increase in bone density, with a slightly lower effect of increasing bone density in the augmentation of bone defects

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BMSCs Seeding in Different Scaffold Incorporation with Hyperbaric Oxygen Treat Seawater Immersed Bony Defect

10.21203/rs.3.rs-44123/v2 ◽

2020 ◽

Author(s):

gan zhang ◽

Xiaosong Chen ◽

Xunsheng Cheng ◽

Xiuwu Ma ◽

Congcong Chen

Keyword(s):

Bone Formation ◽

Bone Defect ◽

Medullary Canal ◽

Bony Defect ◽

New Bone Formation ◽

X Ray ◽

New Zealand White Rabbits ◽

Group A ◽

Group B ◽

Group D

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BMSCs Seeding in Different Scaffold Incorporation with Hyperbaric Oxygen Treat Seawater Immersed Bony Defect

10.21203/rs.3.rs-44123/v1 ◽

2020 ◽

Author(s):

Gan Zhang ◽

Xiaosong Chen ◽

Xunsheng Cheng ◽

Xiuwu Ma ◽

Congcong Chen

Keyword(s):

Bone Formation ◽

Bone Defect ◽

Medullary Canal ◽

Bony Defect ◽

New Bone Formation ◽

X Ray ◽

New Zealand White Rabbits ◽

Group A ◽

Group B ◽

Group D

Abstract Introduction: The experiment was undertaken to estimate the effect of BMSCs seeding in different scaffold incorporation with HBO on the repair of seawater immersed bone defect. And future compared n-HA/PLGA with β-TCP/PLGA as scaffold in treatment effect of seawater immersed bone defect.Methods: 60 New Zealand White rabbits with standard seawater defect in radius were randomly divided to group A (implant with nothing), group B (implanted with atuogenous bone), group C (implanted with n-HA/PLGA/BMSCs, and Group D ( implanted with β-TCP/PLGA/BMSCs). After implant, each rabbit receive HBO treatment at 2.4 ATA 100% oxygen for 120 minutes per day for 2 weeeks. Radiograph, histological and biomechanical examination were used to analyze osteogenesis.Result: X-ray analysis show that n-HA/PLGA/BMSCs and β-TCP/PLGA/BMSCs could accelerate the new bone formation, and the new bone formation in group C was lager than in group D or group A, and close to group B (P < 0.05). After 12 weeks, in group A, defect without scaffold show a loose connect tissue filled in the areas. The medullary canal in group B was recanalizated. Defect in group C and D show a larger number of wove bone formation. The new wove bone formation in defect areas in group C was lager than D. The mechanical examination revealed ultimate strength at 12 weeks were group D > group C > group B > group A(P < 0.05).Conclusion: Scaffold of n-HA/PLGA and β-TCP/PLGA incorporation with HBO and BMSCs were effective to treat seawater immersed bone defect, and n-HA/PLGA was more excellent than β-TCP/PLGA.

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Biphasic Calcium Phosphate/Chitosan/Polyacrylonitrile/Polylactic Acid-Glycolic Acid (PLGA) Nanocomposite Stent for Repair and Osteogenesis of Oral Alveolar Bone Defect

Science of Advanced Materials ◽

10.1166/sam.2021.4039 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1324-1334

Author(s):

Gang Cheng ◽

Hong Chen ◽

Kai Wang ◽

Jinxing Gao ◽

Xiao Li ◽

...

Keyword(s):

Bone Defect ◽

Biphasic Calcium Phosphate ◽

Glycolic Acid ◽

Alveolar Bone ◽

Sol Gel ◽

Bone Defects ◽

X Ray ◽

Defect Area ◽

Group A ◽

Alveolar Bone Defect

ABSTRACTThe ability of sol-gel micro-nano biphasic calcium stent to repair oral alveolar bone defects was investigated in this study, and its osteogenesis performance was also analyzed. Biphasic calcium phosphate (BCP) was synthesized by wet method, which was combined with chitosan (CS), polyacrylonitrile (PAN), and polylactic acid-glycolic acid (PLGA). Then, the BCP/CS/PAN/PLGA nanocomposite stent was prepared by vacuum freeze-drying technology. The micro-nano composite stent was combined with the bone morphogenetic protein-2 (BMP-2) gene, so as to obtain the sol-gel micro-nano biphasic calcium BMP-2/BCP/CS/PAN/PLGA composite stent. Besides, the composite stent should be measured in terms of compressive strength, porosity, structure, and morphological features. The healthy female rhesus monkeys were taken as the research animals, and the iliac bone marrow was extracted by puncture. The mesenchymal stem cells (MSCs) were obtained by density gradient centrifugation, and their osteogenic differentiation ability was observed. The MSCs were cultured in vitro with BMP-2/BCP/CS/PAN/PLGA composite stent, methylthiazolyldiphenyl-tetrazolium bromide (MTT) was applied to detect cell adhesion and proliferation, and the alkaline phosphatase (ALP) activity was employed to analyze its osteogenic properties on stent materials. In addition, the expression of BMP-2 was detected by Western blot. The alveolar bone defect models were established and divided into group A (MSCs + BMP-2/BCP/CS/PAN/PLGA), group B (BMP-2/BCP/CS/PAN/PLGA), group C (BCP/CS/PAN/PLG), and group D (control group, reposition of gingival flap and suture) according to different implant materials. The changes of bone defect area in different groups were detected by gross examinations and X-ray, so that the new bone density was analyzed. The results showed that the BCP/CS/PAN/PLGA composite stent exhibited a porous structure combining multiple pores/small pores, with an average pore diameter (PD) of 400–500 µm, maximum compressive strength of 6.02 Mpa, and porosity of 86.82%. MSCs differentiated into osteoblasts under osteogenic induction conditioned medium, and the optical density (OD) of CS + MSCs/BMP-2/BCP/CS/PAN/PLGA cells was greater in contrast to that of MSCs/BMP-2/BCP/CS/PAN/PLGA cells on the 1st and 7th day of culture, showing a statistical difference (P < 0.05). The gross examination and X-ray of bone defect area in group A showed that its bone structure and density were very close to those of normal bone (all materials were absorbed, and newly formed bone cells were active); the CT value of alveolar bone in groups A, B, C, and D was 1,092.45± 15.87 g/cm3, 932.26± 16.75 g/cm3, 859.51 ±17.86 g/cm3, and 787.96± 16.54 g/cm3, respectively. There was no marked difference in CT values between group A and normal alveolar bone (P > 0.05), while the CT value of alveolar bone in group A was higher obviously than the value of groups C and D (P < 0.05). It indicated that the composite stent based on sol–gel micro-nano biphasic calcium BMP-2/BCP/CS/PAN/PLGA could promote the repair of oral alveolar bone defect and its osteogenesis, thereby providing a reference for the oral clinical treatment of periodontal bone defects.

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A Study of the Relationship between the Polymorphism and Mutation of rs682429 and rs3781590 in the LRP5 Gene and Bone Metabolism in Postmenopausal Type 2 Diabetic Women in Xinjiang

Journal of Diabetes Research ◽

10.1155/2020/3071217 ◽

2020 ◽

Vol 2020 ◽

pp. 1-5

Author(s):

Jun Li ◽

SiYuan Li ◽

HuiRong Zhao ◽

JiaJia Li ◽

Shuang Wang ◽

...

Keyword(s):

Bone Mass ◽

Bone Metabolism ◽

Postmenopausal Women ◽

X Ray ◽

Group A ◽

Mass Group ◽

Group B ◽

The Relationship ◽

Group D

Objective. To explore the expression of the polymorphism and mutation of rs682429 and rs3781590 in the low-density lipoprotein receptor-related protein 5 (LRP5) genotype and to analyse the relationship of bone mineral density (BMD) and bone metabolism markers in postmenopausal women with type-2 diabetes mellitus (T2DM) in Xinjiang, China, to provide a basis for prevention and treatment of the disease. Methods. A total of 136 postmenopausal women were included in the study. According to the results of an oral glucose tolerance test (OGTT) and dual-energy X-ray (DEXA) determination of BMD, the study subjects were divided into 4 groups: group A: normal OGTT+normal bone mass group; group B: normal OGTT+osteoporotic (OP) group; group C: T2DM+normal bone mass group; group D: T2DM+osteoporotic (OP) group. Calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), and clinical biochemical data were determined; haemoglobin A1c (HbA1c) was measured by HPLC; BMD of the femoral neck, hip, and lumbar spine (L1-4) was measured by dual-energy X-ray (DEXA); and the rs682429 and rs3781590 polymorphisms of the LRP5 gene were detected by time-of-flight mass spectrometry (TOF MS). Results. (1) The rs682429 polymorphism of the LRP5 genotype distribution was statistically significant (P<0.05) in group B compared with group A. (2) The triglycerides (TG) of women with the CT/TT genotype (mutant type) were higher than those of women with the CC genotype (wild type) (2.37±1.30 vs. 1.52±0.83, P<0.05) at the rs3781590 site of the LRP5 gene in group D. (3) Multiple linear regression analysis showed that TG (β=0.034, P<0.05) and body mass index (BMI) (β=0.013, P<0.05) were the influencing factors of BMD (L1-4) in T2DM patients. TG (β=0.022, P<0.05), BMI (β=0.009, P<0.05), and duration of menopause (β=0.005, P<0.05) were the influencing factors of BMD (hip). Conclusion. (1) The rs682429 polymorphism site in the LRP5 gene may be involved in bone metabolism in postmenopausal women from Xinjiang. (2) The rs3781590 mutation in the LRP5 gene from these subjects may be involved in lipid metabolism. (3) Among postmenopausal women with type 2 diabetes mellitus and bone mass abnormality in the Xinjiang Shihezi area, high BMI and TG are protective factors against increased BMD. Duration of menopause is a risk factor for increased BMD.

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BMSC seeding in different scaffold incorporation with hyperbaric oxygen treats seawater-immersed bony defect

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02368-8 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Gan Zhang ◽

Xiaosong Chen ◽

Xunsheng Cheng ◽

Wuxiu Ma ◽

Congcong Chen

Keyword(s):

Bone Formation ◽

Bone Defect ◽

Medullary Canal ◽

Autogenous Bone ◽

Bony Defect ◽

New Bone Formation ◽

Woven Bone ◽

Group A ◽

Group B ◽

Group D

Abstract Introduction The experiment was undertaken to estimate the effect of BMSC seeding in different scaffold incorporation with HBO on the repair of a seawater-immersed bone defect. And future compared n-HA/PLGA with β-TCP/PLGA as a scaffold in treatment effect of the seawater-immersed bone defect. Methods Sixty New Zealand White rabbits with standard seawater defect in radius were randomly divided into group A (implant with nothing), group B (implanted with autogenous bone), group C (implanted with n-HA/PLGA/BMSCs), and group D (implanted with β-TCP/PLGA/BMSCs). After the implant, each rabbit receives HBO treatment at 2.4 ATA 100% oxygen for 120 min/day for 2 weeks. Radiograph, histological, and biomechanical examinations were used to analyze osteogenesis. Result X-ray analysis shows that n-HA/PLGA/BMSCs and β-TCP/PLGA/BMSCs could accelerate the new bone formation, and the new bone formation in group C was larger than that in group D or group A and close to group B (P < 0.05). After 12 weeks, in group A, the defect without scaffold shows a loose connect tissue filled in the areas. The medullary canal in group B was recanalized. Defects in groups C and D show a larger number of woven bone formation. The new woven bone formation in defect areas in group C was larger than that in group D. The mechanical examination revealed ultimate strength at 12 weeks was group D > group C > group B > group A (P < 0.05). Conclusion Scaffolds of n-HA/PLGA and β-TCP/PLGA incorporation with HBO and BMSCs were effective to treat seawater-immersed bone defect, and n-HA/PLGA was more excellent than β-TCP/PLGA.

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Novel Piston Technique Versus Ilizarov Technique for The Repair of Bone Defect After Lower Limb Infection

10.21203/rs.3.rs-749905/v1 ◽

2021 ◽

Author(s):

Jiafei Du ◽

Zifei Yin ◽

Pengfei Cheng ◽

Pei Han ◽

Hao Shen

Keyword(s):

Bone Defect ◽

Bone Healing ◽

Lower Limb ◽

Functional Results ◽

Bone Defects ◽

Ilizarov Technique ◽

Group A ◽

The Mean ◽

Group B

Abstract Background We described the use of a novel Piston technique versus Ilizarov technique to compare the effectiveness and complications for the repair of bone defect after lower limb infection. Patients and methods: We retrospectively reviewed 41 patients who had been treated at our department for lower extremity bone defects following osteomyelitis. They were 38 males and 3 females with a mean age of 43.41 (range 12 to 69 years). The infected bone defects involved 36 tibias and 5 femurs. Piston technique (PT, group A) was used in 12 patients and Ilizarov technique (IT, group B) in 29 ones. The mean duration of follow-up was 28.50 months (PT) and 29.90 months (IT). The modified Application of Methods of Illizarov (ASAMI) criteria was used to evaluate the bone healing and functional recovery. Results Complete eradication of infection and union of docking sites were accomplished well in both groups. The mean external fixator index (EFI) was 42.32 days/cm in group A versus 58.85 days/cm in group B (p < 0.001). The bone outcomes were similar between group A and B (p = 0.558) [excellent (9 vs. 19), good (3 vs.10)]; group A showed better functional outcomes than group B (p < 0.05) [excellent (7 vs. 6), good (4 vs. 12), fair (0 vs. 10) and poor (1 vs. 1)]. Pain was complained most during follow-up and group A had fewer cases of pin tract infection (1 vs. 6), adjacent joint stiffness (3 vs. 8) and delayed healing of the joint (0 vs. 3). Conclusions Satisfactory bone healing can be obtained by using both PT and IT, while PT had better functional results, lower EFI and allowed early removal of the external fixation. We have found that this novel Piston technique can improve the comfort of patients, reduce the incidence of complications, and provide a rapid and convenient rehabilitation.

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Repair of long bone defects of large size using a tissue-engineered periosteum in a rabbit model

Journal of Materials Science Materials in Medicine ◽

10.1007/s10856-021-06579-7 ◽

2021 ◽

Vol 32 (9) ◽

Author(s):

Lin Zhao ◽

Junli Zhao ◽

Zhenhe Tuo ◽

Guangtie Ren

Keyword(s):

Bone Regeneration ◽

Rabbit Model ◽

Bone Defects ◽

Long Bone ◽

Clinical Settings ◽

Large Size ◽

Group A ◽

Group B ◽

Intestinal Submucosa ◽

Group D

AbstractTissue engineering is a promising approach for bone regeneration. In this study, we aimed to investigate whether tissue engineered periosteum (TEP), which was fabricated by combining osteogenically-induced mesenchymal stem cells (MSCs) with porcine small intestinal submucosa (SIS), could restore long bone defects of large size in rabbits. Twenty-four adult New Zealand white rabbits (NZWRs) were used in the experiments. Long bone defects of large size (30 mm-50 mm; average, 40 mm) were established on both sides of NZWRs’ radii. The defects were treated with TEP (Group A), allogeneic deproteinized bone (DPB, Group B), TEP combined with DPB (Group C), and pure SIS (Group D). The healing outcome was evaluated by radiography and histological examination at 4, 8, and 12 weeks post-treatment. The radiographical findings showed that bone defects of large size were all repaired in Groups A, B and C within 12 weeks, whereas Group D (pure SIS group) failed to result in defect healing at 4, 8, and 12 weeks. Although there was some new bone regeneration connecting the allografts and bone ends, as observed under radiographical and histological observations, bone defects of large sizes were restored primarily by structurally allografted DPB within 12 weeks. The TEP groups (Groups A and C) showed partial or total bone regeneration upon histological inspection. Based on 12-week histological examinations, significantly more bone was formed in Group A than Group C (P < 0.05), and both groups formed significantly more bone than in Groups B and D. The results indicated that long bone defects of a large size could be restored by TEP or TEP combined with the DPB scaffold, and such materials provide an alternative approach to resolving pathological bone defects in clinical settings.

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Survival of classic swine fever virus in hams made from the meat of pigs vaccinated with the PAV-250 strain and unvaccinated pigs

Revista Mexicana de Ciencias Pecuarias ◽

10.22319/rmcp.v10i3.4528 ◽

2019 ◽

Vol 10 (3) ◽

pp. 536-551

Author(s):

Heidi Amezcua Hempel ◽

María Salud Rubio Lozano ◽

Eliseo Manuel Hernández Baumgarten ◽

Pablo Correa Girón † ◽

Oscar Torres Ángeles ◽

...

Keyword(s):

Reference Strain ◽

Clinical Signs ◽

Classical Swine Fever ◽

Fever Virus ◽

Direct Immunofluorescence ◽

Biometric Analysis ◽

Treatment Groups ◽

Group A ◽

Group B ◽

Group D

The study was to determine the presence of Classical Swine Fever virus (CSFv), in the meat of vaccinated pigs with the PAV-250 strain and then challenged using the same strain. Five treatment groups were established (each with four pigs). Group A: Pigs thatwere fed with processed hams from negative animals; Group B: Pigs that were fed with processed hams from commercial pigs inoculated with the ALD (reference strain) (titre of 104.0/ml); Group C: Pigs fed with processed hams from pigs infected with the virulent ALD strain (titre of 102.5/ml); Group D: Pigs fed with processed hams from pigs vaccinated with the PAV-250 strain and challenged with the ALD strain (titre of 101.1/ml); and Group E: Pigs fed with processed hams from pigs vaccinated with two doses of the PAV-250 strain and challenged with the ALD strain (negative). Blood samples were taken at d 1, 5, 10, 15 and 20 for biometric analysis. Groups B, C and D manifested clinical signs of CSFv: 40 °C temperature, anorexia, paralysis, vomiting, diarrhea, tremor, hirsute hair and cyanosis. Pigs were slaughtered and necropsies performed to identify lesions in tissues. Results of direct immunofluorescence testing of tissues were positive and the virus was recovered. Under these study conditions, it was found that CSFv resisted the cooking method at 68 °C for 40 min in hams from unvaccinated pigs, and that the virus was able to transmit the disease to healthy unvaccinated pigs, whereas the hams from the vaccinated animals did not transmit the virus.

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