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1.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-879553

RESUMEN

DNA methylation as an important aspect of epigenetics plays an important role in spermatogenesis and embryonic development. In recent years, researchers have found that male infertility, in particular abnormal semen quality, is related to abnormal DNA methylation. To further delineate the pathogenesis of male infertility and inspire new ideas for the treatment of male infertility, a comprehensive review over the correlation between abnormal methylation of imprinted genes, repetitive DNA elements and non-imprinted genes, semen quality (including sperm count, morphology, and vitality) and male infertility is provided.


Asunto(s)
Humanos , Masculino , Metilación de ADN , Infertilidad Masculina/genética , Análisis de Semen , Recuento de Espermatozoides , Espermatogénesis , Espermatozoides/patología
2.
Preprint en Inglés | bioRxiv | ID: ppbiorxiv-192104

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an enveloped virus responsible for the COVID-19 pandemic. Despite recent advances in the structural elucidation of SARS-CoV-2 proteins and the complexes of the spike (S) proteins with the cellular receptor ACE2 or neutralizing antibodies, detailed architecture of the intact virus remains to be unveiled. Here we report the molecular assembly of the authentic SARS-CoV-2 virus using cryo-electron tomography (cryo-ET) and subtomogram averaging (STA). Native structures of the S proteins in both pre- and postfusion conformations were determined to average resolutions of 8.7-11 [A]. Compositions of the N-linked glycans from the native spikes were analyzed by mass-spectrometry, which revealed highly similar overall processing states of the native glycans to that of the recombinant glycoprotein glycans. The native conformation of the ribonucleoproteins (RNP) and its higher-order assemblies were revealed. Overall, these characterizations have revealed the architecture of the SARS-CoV-2 virus in unprecedented detail, and shed lights on how the virus packs its [~]30 kb long single-segmented RNA in the [~]80 nm diameter lumen.

3.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-20060160

RESUMEN

The sudden outbreak of the severe acute respiratory syndrome-coronavirus (SARS-CoV-2) has spread globally with more than 1,300,000 patients diagnosed and a death toll of 70,000. Current genomic survey data suggest that single nucleotide variants (SNVs) are abundant. However, no mutation has been directly linked with functional changes in viral pathogenicity. We report functional characterizations of 11 patient-derived viral isolates. We observed diverse mutations in these viral isolates, including 6 different mutations in the spike glycoprotein (S protein), and 2 of which are different SNVs that led to the same missense mutation. Importantly, these viral isolates show significant variation in cytopathic effects and viral load, up to 270-fold differences, when infecting Vero-E6 cells. Therefore, we provide direct evidence that the SARS-CoV-2 has acquired mutations capable of substantially changing its pathogenicity.

4.
Chinese Journal of Orthopaedics ; (12): 760-768, 2020.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-869029

RESUMEN

Objective:To design 3D printed prosthesis in an individualized way and explore the short-term clinical efficacy of reconstruction of segmental defect after resection of bone tumor in lower extremities with 3D-printed prosthesis.Methods:From January 2017 to June 2019, 6 patients with lower limb bone tumor who met the inclusion criteria were recruited, including 3 males and 3 females, aged 8.67±1.11 years (range 6-11 years). All 6 cases were primary bone tumors, and the Enneking stages were all IIB, including 3 cases of left tibial tumors, 2 cases of right tibial tumors, and 1 case of right femoral tumor. These 3D-printed prostheses were designed based on the preoperative imaging data. The mechanical stability of the prosthesis was evaluated by three-dimensional finite element analysis. After tumor resection, the 3D-printed prosthesis was installed and fixed to reconstruct the segmental bone defect. All patients were clinically followed up and evaluated by imaging regularly after operation. The functional status was assessed by the Musculoskeletal Tumor Society (MSTS) score. Oncology results and complications were recorded in detail.Results:All operations were successfully performed, including 3 cases underwent left tibial tumor resection, 2 cases underwent right tibial tumor resection, and 1 case underwent right femoral tumor resection. The length of the bone defect after tumor resection was 18.19±3.74 cm, the average operation time was 165.83±54.17 min, and the average intraoperative bleeding was 233.33±133.33 ml. These finite element analysis data show that the overall stress of these prostheses are lower than the maximum mechanical strength of the corresponding materials. These 3D printed prostheses match well with the excision defect and meet the expected effect. There were no adverse reactions during the operation. The mean follow-up period was 16.83±7.17 months. At the last follow-up, all patients survived without tumor recurrence or metastasis. Postoperative imaging results showed that all the implants were stable without complications such as peripheral infection, aseptic loosening, prosthesis fracture. These 3D-printed prostheses composite resulted in substantial bone integration at follow-up. The average MSTS score was 83.67%±9.11%.Conclusion:The individualized 3D printed prosthesis can be used to reconstruct the bone defect after the resection of osteosarcoma in the lower extremities, and the clinical efficacy was satisfactory in the short-term follow-up.

5.
Clinical Medicine of China ; (12): 935-938, 2017.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-662148

RESUMEN

Objective To investigate the value of diffusion weighted imaging combined with contrast-enhanced MRI(CE-MRI)in activity of sacroiliitis of patients with ankylosing spondylitis(AS).Methods The AS patients diagnosed in Beijing Jishuitan Hospital were selected as the experimental group,and healthy volunteers were selected as the control group.The AS group was divided into the active group and the stable group according to the clinical diagnostic criteria.All subjects were examined with both MRI plain scan and CE-MRI of bilateral sacroiliac joints.ROIs were drawn in the lesion region and the ADC values and signal intensity enhancement rate(△SI)were recorded.△SI and ADC value among the active AS group,chronic group and control group was compared and analyzed.The clinical diagnostic criteria was regarded as the gold standard for the active AS group and the chronic group.The ROC curve was used to evaluate the value of ADC,△SI,ADC, and ADC combined with △SI can detect the efficiency of AS activity.Results Ninety-eight AS patients were enrolled in this study,including 63 cases in the active AS group,35 cases in the chronic AS group,and 23 cases in the control group.The ADC values of the active group,the chronic group and the control group were(1.35 ±0.17)×10-3mm2/s,(1.07±0.20)×10-3mm2/s,(0.36±0.14)×10-3mm2/s,respectively,and ΔSI values were (2.42±0.80)%,(1.28 ± 0.34)% and(0.74 ± 0.22)%.There were significant differences in ΔSI and ADC values among the three groups(F=216.559,56.522.P=0.000).When ADC values were used to assess the activity of AS,the area under the ROC curve was 0.809 and the optimal diagnostic threshold was 1.35×10-3 mm2/s,the sensitivity and specificity of AS activity were 57.1% and 94.3%.When ΔSI values were used,the area under the ROC curve was 0.837 and the sensitivity and specificity were 71.40% and 97.10% with the optimal diagnostic threshold of 1.79%.When ΔSI values were combined with the ADC values,the area was 0.963 and the sensitivity and specificity were 74.6% and 94.3%.Conclusion In assessment of the activity of AS,DWI combined with CE-MRI is most valuable.

6.
Clinical Medicine of China ; (12): 935-938, 2017.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-659481

RESUMEN

Objective To investigate the value of diffusion weighted imaging combined with contrast-enhanced MRI(CE-MRI)in activity of sacroiliitis of patients with ankylosing spondylitis(AS).Methods The AS patients diagnosed in Beijing Jishuitan Hospital were selected as the experimental group,and healthy volunteers were selected as the control group.The AS group was divided into the active group and the stable group according to the clinical diagnostic criteria.All subjects were examined with both MRI plain scan and CE-MRI of bilateral sacroiliac joints.ROIs were drawn in the lesion region and the ADC values and signal intensity enhancement rate(△SI)were recorded.△SI and ADC value among the active AS group,chronic group and control group was compared and analyzed.The clinical diagnostic criteria was regarded as the gold standard for the active AS group and the chronic group.The ROC curve was used to evaluate the value of ADC,△SI,ADC, and ADC combined with △SI can detect the efficiency of AS activity.Results Ninety-eight AS patients were enrolled in this study,including 63 cases in the active AS group,35 cases in the chronic AS group,and 23 cases in the control group.The ADC values of the active group,the chronic group and the control group were(1.35 ±0.17)×10-3mm2/s,(1.07±0.20)×10-3mm2/s,(0.36±0.14)×10-3mm2/s,respectively,and ΔSI values were (2.42±0.80)%,(1.28 ± 0.34)% and(0.74 ± 0.22)%.There were significant differences in ΔSI and ADC values among the three groups(F=216.559,56.522.P=0.000).When ADC values were used to assess the activity of AS,the area under the ROC curve was 0.809 and the optimal diagnostic threshold was 1.35×10-3 mm2/s,the sensitivity and specificity of AS activity were 57.1% and 94.3%.When ΔSI values were used,the area under the ROC curve was 0.837 and the sensitivity and specificity were 71.40% and 97.10% with the optimal diagnostic threshold of 1.79%.When ΔSI values were combined with the ADC values,the area was 0.963 and the sensitivity and specificity were 74.6% and 94.3%.Conclusion In assessment of the activity of AS,DWI combined with CE-MRI is most valuable.

7.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-490699

RESUMEN

Objective To study and summary the treatment of talus fracture. Methods Fifteen patients with talus fracture were treated by limited cut off reduction by leverage and hollow lag screw under C arm X-Ray machine January 2008 to November 2014, of whom there were 11 males and 4 females, aged 15-61 years old. Seven patients sufferred from talus fracture because of traffic accidents, 4 patients because of falls, 2 patients because of crush injury, and 2 patients because of sprains. Hawkins typing:Ⅰtype in 1 patient, Ⅱ type in 6 patients, Ⅲ type in 6 patients of Ⅲ type, and Ⅳ type in 2 patients. Results Followed up for 6 months to 4 years (mean 1.5 years), fracture healed better. Hawkins grading standard:9 patients showed excellent (1 patient ofⅠtype, 5 patients ofⅡtype, 3 patients ofⅢtype), and two patients showed good (Ⅲtype). The excellent and good rate was 11/15. Necrosis of talus occurred in one patient, and degenerative joint disease occured in one patient. Conclusions Minimally invasive internal fixation with hollow lag screw under C arm X-Ray machine in the treatment of talus fracture has a small injury to the periosteum and the blood supply of small soft tissue. It can fix reliably and can pressurize the fracture fragments, and is conducive to fracture healing.

8.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-487973

RESUMEN

Objective To explore the effects of low load exercise on the gait and balance in patients with Parkinson's disease. Methods 12 inpatients with Parkinson's disease from May to August, 2015 accepted low load exercise on Power Rehabilitation System 14 times in 2 weeks, with the medication as before. They were assessed with 3D gait analysis and Berg Balance Scale before and after treatment. Results The step length, stride length and walking speed improved after treatment (P0.05). The scores of Berg Balance Scale improved after treatment (P<0.05). Conclusion The low load exercise can improve the gait and balance in patients with Parkinson's disease.

9.
The Journal of Practical Medicine ; (24): 2677-2679, 2016.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-498119

RESUMEN

Objective To establish a Loop-mediated Isothermal Amplification (LAMP) for Pseudomonas aeruginosa rapid detection. Method 152 P. aeruginosa strains isolated from nasal swabs and 30 reference strains were applied. P. aeruginosa ATCC15442 was used to develop LAMP amplification and evaluate sensitivity and specificity. Results Sensitivity of LAMP was 103 times higher than PCR, with DNA amount as 132 fg. When LAMP was applied to 30 reference strains and 152 P. aeruginosa strains , the specification was 100% while iden-tification rate reached 94.7%. Conclusion The establishment LAMP showed a promising prospect in P. aerugi-nosa rapid detection.

10.
China Pharmacy ; (12): 4057-4059,4060, 2015.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-605058

RESUMEN

OBJECTIVE:To provide reference for rational drug use in the clinic. METHODS:By retrospective survey meth-od,the drug utilization of IVF outpatient department in our hospital during Jun. 2012-May 2014 were analyzed statistically in re-spects of consumption structure,consumption sum and DDDs,etc. RESULTS:Oral medicine was major type of medicines in IVF outpatient department,followed by injection;total consumption sum was on the rise,and the sum of injection accounted for large proportion. Ovulation stimulants and sex hormone class medicine,vitamin and other nutritional drugs were main drugs used in IVF outpatient department. The consumption sum and DDDs showed obvious asynchronism. CONCLUSIONS:The drug use is reason-able on the whole. But expensive ovulation stimulants increase the economic burden of patients to some extent.

11.
Acta Pharmaceutica Sinica ; (12): 558-65, 2014.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-448620

RESUMEN

Single nucleotide polymorphisms (SNP) is an important molecular marker in traditional Chinese medicine research, and it is widely used in TCM authentication. The present study created a new genotyping method by combining restriction endonuclease digesting with melting curve analysis, which is a stable, rapid and easy doing SNP genotyping method. The new method analyzed SNP genotyping of two chloroplast SNP which was located in or out of the endonuclease recognition site, the results showed that when attaching a 14 bp GC-clamp (cggcgggagggcgg) to 5' end of the primer and selecting suited endonuclease to digest the amplification products, the melting curve of Lonicera japonica and Atractylodes macrocephala were all of double peaks and the adulterants Shan-yin-hua and A. lancea were of single peaks. The results indicated that the method had good stability and reproducibility for identifying authentic medicines from its adulterants. It is a potential SNP genotyping method and named restriction endonuclease digest - melting curve analysis.

12.
Acta Pharmaceutica Sinica ; (12): 124-30, 2014.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-448753

RESUMEN

By reverse transcription-polymerase chain reaction (RT-PCR), an open reading frame of pathogenesis-related protein 1 (PR1) was isolated from Panax notoginseng and named as PnPR1. Molecular and bioinformatic analyses of PnPR1 revealed that an open reading frame of 501 bp was predicted to encode a 166-amino acid protein with a deduced molecular mass of 18.1 kD. Homology analysis showed that the deduced amino acid sequence of PR1 protein of Panax notoginseng had a high similarity with other higher plants had the same conservative structure domain of cysteine-rich secretory protein (CAP). The recombinant expressed plasmid pET28a(+)-PnPR1 was expressed in Escherichia coli BL21. The expression conditions were optimized by induction at different times, different temperatures, different IPTG concentrations and different giving times. The optimum expression condition was 0.4 mmol.L-1 IPTG at 28 degrees C for 20 h. The successful expression of PnPR1 provides some basis for protein purification and preparation of the monoclonal antibody.

13.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-431059

RESUMEN

Objective To prepare a novel monoclonal antibody (mAb) that specifically against Mycobacterium tuberculosis culture filtrate protein 10 (CFP-10).Methods The BALB/c mice were immunized by a peptide with 14 amino acids (aa residues 53 to 66) of CFP-10,and then the splenocytes of mice were fused with myeloma cell line SP2/0.The resultant fused cells were subjected to screening culture,enzyme linked immunosorbent assay (ELISA) assay and subcloning by limited dilution to establish hybridoma cell lines of stable secreting anti-the peptide of CFP-10 antibody.The antibody was purified,and its isotypes were analyzed.Then,the antibody was further evaluated by Western blotting,immunoprecipitation and ELISA in 38 culture supernatant samples of Mycobacterium tuberculosis,20 culture supernatant samples of non-Mycobacterium tuberculosis,32 samples of tuberculous pleural effusion,24 samples of non-tuberculous pleural effusion,and 20 serum samples from healthy controls.Results The isotype of the mAb against the specific peptide of CFP-10 was an IgG1 with κ chain,and it was applicable for Western blotting and immunoprecipitation analysis.ELISA quantitative test showed that the sensitivity and specificity for diagnosis of Mycobacterium tuberculosis were 78.6% (55/70) and 92.2% (59/64),respectively.Conclusion The mAb generated against the specific peptide of CFP-10 is high in sensitivity and specificity,and it might be used in the early diagnosis of tuberculosis.

14.
Acta Pharmaceutica Sinica ; (12): 1394-8, 2012.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-431052

RESUMEN

A FatB unigene was obtained from the transcriptome dataset of Lonicera japonica Thunb. Full-length FatB cDNA was cloned from buds of Lonicera japonica Thunb., Lonicera japonica Thunb. var. chinensis (Wats.) Bak., Lonicera hypoglauca Miq. and Lonicera dasystyla Rehd. using RT-PCR technology, and named as LJFatB, LHFatB, LJCFatB and LDFatB. The results of bioinformatic analysis showed that LJFatB, LJCFatB, LHFatB and LDFatB and Arabidopsis thaliana AtFatB had a closely relationship. Nucleotide sequences and protein secondary structure of LJFatB, LJCFatB, LHFatB and LDFatB are different and their proteins had conserved FatB substrate binding sites and catalytic activity sites. Transcriptive level of LJFatB, LJCFatB, LHFatB and LDFatB in bud was not significantly different. Therefore, LJFatB, LJCFatB, LHFatB and LDFatB could have the same biological function as AtFatB.

15.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-419260

RESUMEN

ObjectiveTo evaluate the efficacy of stereotactic body radiotherapy combined with coinstan taneous gemcitabine,and gemcitabine alone for advanced pancreatic cancer.Methods56 advanced pancreatic cancer patients were assigned into observation group,which accepted stereotactic body radiotherapy combined with coinstantaneous gemcitabine 500 mg/m2,d1,d8.Other 50 patients were assigned into the control group which only accepted gemcitabine 1 000 mg/m2,d1,d8,d15.Stereotactic body radiotherapy was delivered with a total dose of 4 000-4 500 cGy in 10 fractions.ResultsCT examinations were carried out 2 months after treatment.The response rate of the observation group and control group was 82% and 16% respectively,and the pain relief rate was 67% and 17% respectively.The time to progression of the observation group was 14 months,and was better than that of the control group(7.5 months,x2 =7.31,P =0.032).The median survival time of the observation group and control group was 15.8 months and 13.2 months,and the difference had no statistical significance(x2 =3.28,P =0.082).ConcolusionStereotactic body radiotherapy combined with gemcitabine has a better overall response rate and a pain relief rate.It can prolong the time to progression,but can't improve the overall survival.

16.
Chinese Journal of Orthopaedics ; (12): 605-610, 2011.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-416673

RESUMEN

Objective To investigate the effects of combined use of an allograft and vascularized fibular flap for the reconstruction of bone defects after intercalary resection of long bone malignancy.Methods From April 2006 to October 2009,19 patients that had intercalary resection of long bone malignancy (5 in humerus,7 in femur,7 in tibia)underwent reconstruction with an allograft and vascularized fibula construct,including 11 males and 8 females with an average age of 18.5 years.The average length of the defect was 13.2±4.3 cm.Free vascularized fibula flaps were used in 16 patients and ipsilateral pedicle vaseularized fibula grafts in 3.Time to union was recorded through evaluation of plain radiographs.Bone scan was used to evaluate the viability of the vascularized fibula.Patients were examined oncologically and radiographically and were assessed functionally with MSTS-93.Results The mean follow-up time was 27.5 months.The average length of the fibula flap was 17.9±5.2 cm.Viability of the fibular grafts was verified in all cases.The average time for bone union at allograft-host junction was 11.3±2.8 months in femur,14.1±3.3 in tibia,6.8±1.4 in humerus,respectively.The MSTS-93 average score at final follow-up was 95.2% in upper extremity and 91.8% in lower extremity.The oncology result in patients with follow-up more than 2 years was continuous disease free in 11 patients.no evidence of disease after recurrence following resection in 1,alive with tumor in 1,and died of lung metastasis in 1.Conclasion Vascularized fibular flap in combination with massive allograft provide an option for reconstruction of large bony defects after long bone malignancy extirpation.The viability of the fibula is a cornerstone in success of reconstruction that prevents allograft nonunion and result in decreased time to bone healing,leading to earlier patient's recovery of function.

17.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-285367

RESUMEN

<p><b>OBJECTIVE</b>To compare the differences in shapes and properties and the microscopic frameworks of the wild and cultivated Radix Salviae Miltiorrhizae from different regions.</p><p><b>METHOD</b>The differences in the shapes and properties, the characters of transverse sections, the powder and disintegrated tissue of roots were compared using microscopic measurement and statistics analysis.</p><p><b>RESULT</b>The wild Radix Salviae Miltiorrhizae had several long cylinder roots with rough flaky squama skin and brown red or wine culour, the cultivated had root of many branch with cling skin and brick-red or chestnut culour. The difference of microscopic histological structure was that the xylem vessel of wild Radix Salviae Miltiorrhizae had bunched vessel with the rank form of big diameter alternating with small diameter, and had stone cell on samples from some producing region, the xylem vessel of the cultivated had no bunched vessel and no stone cell with the rank form of tangential radial. Radix Salviae Miltiorrhizae cultivated in Sichuan Province is called original-region medicinal materials and named Chuandanshen. Chuandanshen had the differences with the Salviae Miltiorrhizae Radix cultivated in other region. The root of Chuandanshen had 1.2 cm diameter, and was bulky and fat with solid fabric and the fracture with brownish yellow color and cutin-alikeness, its xylem vessel of transverse section of root was thin with the rank form of tangential radial, and 19-24 vascular bundle and a few wood fiber.</p><p><b>CONCLUSION</b>Salviae Miltiorrhizae Radix of the wild and the cultivated, of the original-region (Chuandanshen) and the other-region, have the differences in the shapes and properties, and the microscopic frameworks. The character can be identified by the differences in the shapes of medicinal materials, and the rank form of vascular bundle of transverse section of root.</p>


Asunto(s)
China , Microscopía , Control de Calidad , Salvia miltiorrhiza , Química
18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-346981

RESUMEN

This article assessed the genetic relationship and genetic diversity in Dioscorea alata. Twenty samples were examined to identify their original plants, and analyzed by ISSR markers. The results showed that 20 samples were classified into three different plants, such as D. alata, D. persimilis, and D. fordii. There was significant difference in genetic similarity coefficient between D. alata and D. persimi as well as D. fordii. There was distinct differences in D. alata, the genetic similarity coefficient was resulted from 0.672 9 to 0.990 7. With UPGMA clustering method, 16 samples of D. alata could be divided into 4 groups. After comparing samples with the phenotypic characteristics of original plants, it showed that the color and the number of tuber were the most important characteristics of judging the genetic relationship of D. alata. It is concluded that the genetic variation of Dioscorea spp is significant, especially the genetic diversity in D. alata were in a high level. This article supplied a molecular biologic support for distinguishing Dioscorea spp, and also provided basis for breeding of D. alata.


Asunto(s)
ADN de Plantas , Genética , Dioscorea , Clasificación , Genética , Variación Genética , Filogenia , Secuencias Repetitivas de Ácidos Nucleicos
19.
Chinese Journal of Trauma ; (12): 1123-1128, 2009.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-391895

RESUMEN

Objective To investigate the effects of a novel |3 titanium fixation with high strength and low elastic modulus on bone healing of osteoporotic fracture and its effects on stress shielding.Methods Forty female Sprague-Dawley rats were oophorectomized before establishment of femur fracture model.The fracture of left femur was stabilized by titanium alloy pin with high elastic modulus (110 Gpa,high elasticity modulus group) and the fracture of right femur by titanium alloy pin with low elastic modu-lus (30 Gpa, low elasticity modulus group).Six and 12 weeks later, the bone volume (BV) , total vol-ume (TV) and bone volume fraction (BVF) were detected by Micro-CT, and the maximum load was de-tected by biomechanical test.The effects of two titanium alloy pins on formation of bony calluses and me-chanical properties of bones were compared.Results Compared with the low elasticity modulus group, more collagen and bony callus, thicker bone trabeculae and more regular lamellar bone were found in the high elasticity modulus group.In low elasticity modulus group, TV (ROI1) was increased obvious-ly at week 6, with no statistical differences in BV (ROI 1), BV (ROI 2) and maximum load between two groups (P < 0.05).TV and BV in region ROI 1 in the low elasticity modulus group were significantly higher than that in high elasticity modulus group (P < 0.05) , while BV in region ROI 2 in low elasticity modulus group was significantly higher than that in high elasticity modulus group at week 12 postoperative-ly (P<0.05).Biomechnical test indicated that the maximum load in low elasticity modulus group was higher than that in high elasticity modulus group.Conclusions The novel B titanium alloy with high strength and low elastic modulus helps reduce effects of stress shielding, diminish bone resorption, in-crease the fibrous callus formation at the initial phase and improve the quality of bone healing at the later phase.

20.
Journal of Biomedical Engineering ; (6): 1185-1188, 2005.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-309926

RESUMEN

To investigate the effect of three kinds of polymeric scaffolds on attachment, proliferation and differentiation of bone marrow mesenchymal stem cells, the cells were different polymeric scaffolds of PLA-PEG, PLA, PLGA, respectively. The proliferation of cell was evaluated by cell count; the attachment and morphology of BMSCs were observed by SEM; and differentiation was detected by alkaline phosphatase activity, fluorescence, and RT-PCR methods. Results showed that the cells in PLGA group spread better among BMSCs adhered to the three polymeric scaffolds. The activity of ALP was detected after 3 days culture in these three groups. There were no significant differences between PLA-PEG and PLGA groups, but the activity of ALP was higher than PLA group. The gene expressions of osteocalicin and collagen I were also observed in the early culture time. Calcium nodes formation in these polymeric scaffolds were detected. BMSC spreading first, then overlapping growth and secretion of matrix around the bottom and surface of scaffolds were observed through SEM. In summary, PLA-PEG and PLGA are better polymeric scaffolds for the bone tissue engineering, compared with PLA.


Asunto(s)
Células de la Médula Ósea , Biología Celular , Adhesión Celular , Proliferación Celular , Ácido Láctico , Química , Células Madre Mesenquimatosas , Biología Celular , Poliésteres , Química , Polietilenglicoles , Química , Ácido Poliglicólico , Química , Polímeros , Química , Ingeniería de Tejidos , Andamios del Tejido
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