RESUMEN
The differential transformer is an important component in the front-end electronics of high-precision capacitive position sensing circuits, which are widely employed in space inertial sensors and electrostatic accelerometers. The position sensing offset, one of the space inertial sensors' most critical error sources in the performance range, is dominated by the differential transformer asymmetry and requires a high-precision evaluation. This paper proposes a method to assess differential transformers' asymmetry and realize a prototype circuit to test a transformer sample. The results show that the asymmetry measurement precision can achieve 0.6 ppm for the transformer with an asymmetry level of about -278.2 ppm.
RESUMEN
Hypertonic dextrose prolotherapy (HDP) is an injection of a concentrated dextrose solution for the purpose of local treatment of musculoskeletal pain and possible enhancement of repair mechanisms. This systematic review and meta-analysis examines the clinical utility of HDP injection for treatment of knee osteoarthritis (OA). Randomized controlled trials (RCTs) utilizing HDP to treat knee OA were retrieved from MEDLINE, EMBASE, and Cochrane Library (CENTRAL). Identification and inclusion of RCTs utilizing intra-articular and extra-articular administration of HDP vs administration of other injectate or physical therapy as control for knee OA were included. Primary clinical outcomes were changes in knee WOMAC, pain and function score. Secondary outcomes were adverse events related to HDP. For continuous outcomes with same or different measurements, we calculated, respectively the weighted mean difference (WMD) or the standardized mean difference (SMD), respectively. Results were pooled using DerSimonian and Laird random effect models across the included studies and heterogeneity between studies was estimated using the I2 index. Five studies comprising a total of 319 treated patients met inclusion criteria and were included in the final analysis. At a mean of 22.8 weeks follow-up, HDP treatment significantly improved total WOMAC score (WMD = 13.77, 95% CI: 6.75-20.78; p < 0.001; I2 = 90%), pain (SMD = 1.33, 95% CI: 0.49-2.17; p < 0.001; I2 = 91%) and knee function (SMD = 1.30, 95% CI: 0.45-2.14; p < 0.001; I2 = 91%) compared with control group. There were no severe adverse events related to dextrose injection reported in all the included studies. HDP is a promising treatment for knee OA with a reasonable safety profile. Further research in mechanism of HDP activity and long-term follow-up study will be needed for exploring this novel therapy modality.
Asunto(s)
Osteoartritis de la Rodilla , Proloterapia , Glucosa , Humanos , Inyecciones Intraarticulares , Dolor/tratamiento farmacológico , Proloterapia/métodos , Resultado del TratamientoRESUMEN
OBJECTIVE: To investigate the biomechanical effect of different intervertebral reconstructive heights on adjacent segments following C5 /C6 anterior cervical discectomy and fusion (ACDF) through finite element analysis. METHODS: A finite element model of intact C4 -C7 segments was developed and validated for the present study. Five additional C4 -C7 postoperative models were constructed with 100%, 125%, 150%, 175%, and 200% of the benchmark height of C5 /C6 on the basis of the intact model. The changes in intradiscal pressure (IDP) and range of motion (ROM) of adjacent segments before and after reconstruction of C5 /C6 were analyzed. RESULTS: For the upper adjacent segment (C4 /C5 ), the IDPs under the different loading conditions all increased after reconstruction. The maximum IDPs were 0.387, 0.489, 0.491, and 0.472 MPa under flexion, extension, axial rotation, and lateral bending, respectively, observed at the reconstructive height of 200%. The minimum IDPs were observed at 150% reconstructive height under all loading conditions except extension, and were 57, 86 and 81% of the maximum IDPs under flexion, axial rotation, and lateral bending, respectively. The minimum IDP under extension occurred when the reconstructive height is 125% of the benchmark height. For the lower adjacent segment (C6 /C7 ), the IDPs of postoperative models under all loading conditions also increased compared to the preoperative model. The maximum IDPs after reconstruction under flexion, extension, axial rotation, and lateral bending were 0.402, 0.411, 0.461, and 0.497 MPa, respectively, when the height of the reconstruction was 200% of the benchmark. The minimum IDPs were observed after a reconstruction at 150% of the benchmark, and were 59%, 85%, 82%, and 81% of the maximum IDPs under flexion, extension, axial rotation, and lateral bending loading conditions. CONCLUSIONS: The reconstructive height is an important factor affecting the IDP and the ROM of adjacent segments after ACDF. To delay the adjacent segment disease, an intervertebral reconstructive height of 150% is an appropriate height in C5 /C6 ACDF.
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Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Discectomía/métodos , Imagenología Tridimensional , Fusión Vertebral/métodos , Adulto , Fenómenos Biomecánicos , Análisis de Elementos Finitos , Voluntarios Sanos , Humanos , Masculino , Rango del Movimiento Articular , Tomografía Computarizada por Rayos XRESUMEN
In this study, we report the complete mitochondrial genome sequence of the European wild boar, Sus scrofa scrofa for the first time. The genome is found to be 16,770 bp in length and has a base composition of A (34.63%), G (13.38%), C (26.21%), and T (25.78%), indicating that the percentage of A + T (60.41%) was higher than G + C (39.59%). Similar to other pigs, it contains a typically conserved structure including 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and 1 control region (D-loop). Most of the genes were located on the H-strand except for the ND6 gene and eight tRNA genes. The complete mitochondrial genome sequence provided here would add a new genetic resource and new study on the evolution of the genus Sus.
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Genoma Mitocondrial , Sus scrofa/genética , Animales , Composición de Base , Codón , Reordenamiento Génico , Genes Mitocondriales , Tamaño del Genoma , Sistemas de Lectura Abierta , Secuencias Reguladoras de Ácidos Nucleicos , Análisis de Secuencia de ADN , Sus scrofa/clasificación , Secuenciación Completa del GenomaRESUMEN
OBJECTIVE: To investigate the effect of pulsed electromagnetic tields (FEMFs) on osteogemc differentiation and Wnt/ß-catenin signaling pathway in rat bone marrow mesenchymal stem cells (BMSCs). METHODS: Rat BMSCs were isolated and the passage 3 cells were divided into 3 groups. Cells were cultured in LG-DMEM complete medium for 1 d to ensure fully adherent. Then, change the medium. Cells were maintained in complete medium (Control group) or in osteo-induction medium (OM group). The cells in PEMFs group were cultured in complete medium and exposed to 8 Hz, 3. 8 mT PEMF stimulation for 40 min/d. The intervention lasted for 21 d. Cell proliferation activity was determined by using MTT. The effects of PEMF onosteogenic differentiation were assessed by ALP and Alizarin Red S staining. Various osteoblast-relevant genes and genes of Wnt/ß-catenin signaling were analyzed by quantitative real-time RT-PCR. RESULTS: We. found that OM could significantly promote the proliferation of BMSC at 7 d, 14 d, 21 d (P<0. 05), but the effect was not obviously found in PEMFs group. For osteogenic differentiation, the positive rates of ALP or Alizarin Red S staining were detected higher in PEMFs/ OM group (P < 0. 05). Quantitative RT-PCR revealed PEMFs or OM could increase mRNA levels of Wnt1, Wnt3a, LRP5, ß-catenin, BMP-2, Runx2, ALP, OC at special time point (P<0. 05). Compared to OM group, PEMFs have a lower expression in each detection, but the trends were consistent. CONCLUSION: PEMFs (8 Hz, 3. 8 mT) could induce the osteogenic differentiation of rat BMSCs via activating Wnt/ß-catenin signaling pathway.
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Campos Electromagnéticos , Células Madre Mesenquimatosas/citología , Osteogénesis , Vía de Señalización Wnt , Animales , Diferenciación Celular , Células Cultivadas , Osteoblastos/citología , Ratas , Proteína Wnt1/metabolismo , beta Catenina/metabolismoRESUMEN
OBJECTIVE: To investigate the effects of whole body vibration therapy (WBVT) on structural and functional remodeling of subchondral bone in rabbits with early Osteoarthritis (OA). METHODS: Twenty-four adult rabbits received anterior cruciate ligament transaction (ACLT) to establish knee osteoarthritis model. The rabbits were randomly divided into two groups: ACLT group and WBVT+ ACLT group. The rabbits in the WBVT+ ACLT group received whole body vibration treatment (Frequency: 40 Hz; Amplitude: 2-4 mm; 40 min/d, 5 d/week, 4 weeks) two months after surgery. After interventions, the left femur and tibia of all rabbits were placed in a Micro-CT scanning system. The bone volume fraction (BVF), trabecular thickness (Tb. Th), trabecular spacing (Tb. Sp), trabecular number (Tb. N), volumetric BMD (vBMD), and tissue BMD (tBMD) of the bones of femoral condyle and tibia were analysed using three-dimensional reconstruction Micview V2.1.2 and ABA analysis software. Geomagic Studio 11.0 software were used to calculate modulus (EM), reaction force (RF) and average Von Miss stress (VMF). RESULTS: Higher levels of BVF, Tb. N, Tb. Th, EM, RF, VMF, vBMD and tBMD and lower levels of Tb. Sp were found in distal femora and tibia of the rabbits in the WBVT+ACLT group compared with the controls (P < 0.05). CONCLUSION: WBVT can effectively improve bone microstructure and mechanical properties of rabbits with early knee osteoarthritis.
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Remodelación Ósea , Osteoartritis de la Rodilla/terapia , Vibración , Animales , Ligamento Cruzado Anterior/patología , Huesos/patología , ConejosRESUMEN
OBJECTIVE: To investigate the role of extracorporeal shock wave therapy on the protection of cartilage and subchondral bone remodeling in rabbits with osteoarthritis induced by anterior cruciate ligament transaction (ACLT). METHODS: Anterior cruciate ligament transaction was performed on 24 adult rabbits to establish knee osteoarthritis models. The rabbits were randomly divided into two groups, with one group receiving extracorporeal shock wave therapy (ESWT) and the other group serving as controls. The ESWT was set at energy 0.16 MPa/time, frequency 5 Hz, 1 200 shock per side, 3 times per week, and a total of 6 times in 4 weeks. Histological observations were undertaken with articular cartilages under mascroscope and microscope; bone mineral density (BMD) was measured. The subchondral bones of femoralcondyle and tibial plateau were given a bone histomorphometry analysis. The levels of interleukin-1 beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha) and nitric oxide (NO) were detected by ELISA. The expressions of matrix metalloproteinases (MMP-1, MMP 3, MMP-13) and tissue inhibitor of metalloproteinases 1 (TIMP-1) in cartilage were determined by RT-PCR. RESULTS: Lower levels of histological result in medial femoral condyles (by both mascroscope and microscope examinations) and higher levels of BMD (in distal femora) were found in the ESWT treated rabbits compared with the controls (P < 0.05). The ESWT treated rabbits also had decreased trabecular bone relative volume and trabecular bone thickness, increased bone separation, lower levels of expressions of MMP-1 and MMP-3, and higher levels of TIMP-1. CONCLUSION: ESWT can protect cartilage from damages and prevent subchondral sclerosis through regulating MMP-1, MMP-3 and TIMP-1 in cartilages and modulating subchondral bone metabolisms.
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Remodelación Ósea , Modelos Animales de Enfermedad , Osteoartritis de la Rodilla/terapia , Animales , Ligamento Cruzado Anterior/patología , Densidad Ósea , Huesos , Cartílago Articular/patología , Interleucina-1beta/metabolismo , Articulación de la Rodilla/patología , Metaloproteinasas de la Matriz/metabolismo , Óxido Nítrico/metabolismo , Conejos , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
OBJECTIVES: To investigate the validity of catalase recombinant adenovirus on the treatment of oxidative cataract. METHODS: The coding sequence of catalase was cloned and the catalase recombinant adenovirus was constructed. The expression time course of catalase gene in rat lens infected by recombinant adenovirus was determined by Western blotting. Cultured rat lens were randomly divided into 3 groups: the control group, the group treated by hydrogen peroxide and the group treated by hydrogen peroxide combined with catalase recombinant adenovirus. The transparence and apoptosis ratio of lens on the time points of 6, 12, 18, 24 hours were determined by image analysis and double colour flowcytometry. RESULTS: The coding sequence of catalase was cloned and recombinant adenovirus was successfully constructed. The expression of catalase in cultured rat lens infected by recombinant adenovirus reached peak point on 9 hours post infection and maintained the level in the whole experiment period. The transparence of the lens in the group treated by hydrogen peroxide combined with catalase recombinant adenovirus was higher than that of group treated by hydrogen peroxide and lower than that of the control group on the time points of 6, 12, 18, 24 hours post infection. The differences among groups were statistically significant (P < 0.05). On the same time points, the apoptosis ratio of the group treated by hydrogen peroxide combined with catalase recombinant adenovirus was lower than that of the group treated by hydrogen peroxide and higher than the control group. The differences among groups were statistically significant (P < 0.05). CONCLUSION: The catalase recombinant adenovirus, which can inhibit the turbidity and cell apoptosis of lens caused by oxidant, may be used as the gene therapy of oxidative cataract.