Evaluation of full thread screw and different fixation configurations in Pauwels type III femoral neck fracture.

Objectives: The purpose of this study is to evaluate the value of full thread screw and different fixation configurations in Pauwels type III femoral neck fracture. Methods: A total of 40 artificial femoral model specimens were chosen, and Pauwels type III femoral neck fracture was simulated upon osteotomy at 80°. According to random number table, models were divided into four groups (10 cases in each group): Group A received the paralleled fixation with three partial thread screws (PTSs), group B received the crossed fixation with three PTSs, group C received the paralleled fixation with two full thread screws (FTSs) and one PTS, and group D received the crossed fixation with two FTSs and one PTS. Changes including the model rigidity, axial displacement in fatigue test and limit loads for Pauwels type III femoral neck fracture models were analyzed through MTS 858 Mini Bionix Ⅱ test system. Results: Among four groups, the model rigidity, axial displacement in fatigue test and limit loads were the highest in group D, and they were the lowest in group A. However, the model rigidity, axial displacement in fatigue test and limit loads between group B and group C showed no statistically significant difference (P＞0.05). Eventually, all the specimens were displaced along the fracture lines while the femoral head was split at varying degrees. After splits, the removal rate of fixation screws in group A (60.0 %) and group C (40.0 %) was significantly higher than that of group B (10.0 %) and group D (0 %) (P＜0.05), but it showed no statistically significant difference between group A and group C, and between group B and group D (P＞0.05). Conclusions: The crossed fixation configuration with two FTSs and one PTS in group D is proven to be more effective, which can go against the shear stress, tension and introversion in Pauwels type III femoral neck fracture models.

Osteoporosis in patients with rheumatoid arthritis is associated with serum immune regulatory cellular factors.

OBJECTIVE: Osteoporosis (OP) is a comorbidity of rheumatoid arthritis (RA) that largely causes disability. This study discussed the expression patterns of serum immunoregulatory factors and their clinical significance in RA patients complicated with OP. METHODS: A total of 116 RA patients were enrolled. Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry to allocate patients to OP group (N = 62) and non-OP group (N = 54). CRP, rheumatoid factor, IgG, IgA, and IgM were detected using rate nephelometry. Erythrocyte sedimentation rate (ESR) and bone metabolic indexes were detected using Microsed automatic ESR analyzer and Cobas e601 automated immunoassay systems and reagents. IL-17, IL-6, TNF-α, IL-10, and IL-4 levels were determined using ELISA kit and their prediction values on OP were analyzed using the ROC curve. Influencing factors of OP incidence were analyzed using logistic regression model. RESULTS: RA patients with OP showed increased age, disease course, tender and swollen joints, ESR, CRP, DAS28 scores, ß-CTX, IL-17, IL-6, and TNF-α, and decreased 25(OH)D3, IL-10, and IL-4. DAS28 was positively correlated with IL-17, IL-6, and TNF-α, and negatively correlated with IL-10 and IL-4. DAS28, IL-17, IL-10, and IL-4 were independently correlated with OP in RA patients. The combination of DAS28, IL-17, IL-10, and IL-4 can better predict the incidence of OP complication in RA patients. CONCLUSION: IL-17, IL-6, TNF-α, IL-10, and IL-4 were associated with disease activity of RA patients complicated with OP. A combination of DAS28, IL-17, IL-10, and IL-4 might predict OP incidence in RA patients.

Long non-coding RNA LINC00265 promotes proliferation, apoptosis, and inflammation of chondrocytes in osteoarthritis by sponging miR-101-3p.

Long non-coding RNAs (lncRNAs) play a part in a wide variety of diseases, including osteoarthritis (OA). This study was designed to investigate the biological role of lncRNA LINC00265 in OA and its underlying mechanisms. We examined the levels of LINC00265 and miR-101-3p using RT-qPCR, inflammatory factors using ELISA, and caspase-3, c-caspase-3, Bcl-2, Bax, and MMP-13 levels using Western blot in normal and OA chondrocytes, analysed the relationship between LINC00265 and miR-101-3p using bioinformatics analysis and luciferase reporter assays, performed loss- and gain-of-function analyses. The results showed that (1) LINC00265 expression was increased in OA chondrocytes, (2) si-LINC00265 inhibited OA chondrocyte apoptosis and inflammation, and (3) LINC00265 overexpression promoted normal and OA chondrocyte apoptosis and inflammation. Furthermore, we predicted and confirmed that miR-101-3p was a target of LINC00265. LINC00265 negatively regulated miR-101-3p in OA chondrocytes and LINC00265 promoted OA and normal chondrocyte apoptosis via miR-101-3p. Overall, lncRNA LINC00265 regulates chondrocyte apoptosis by acting as a sponge of miR-101-3p in OA.

MicroRNA-140-5p represses chondrocyte pyroptosis and relieves cartilage injury in osteoarthritis by inhibiting cathepsin B/Nod-like receptor protein 3.

Osteoarthritis (OA) is a degenerative joint disease. Dysregulated microRNA (miRNA) expressions are implicated in OA progression. Consequently, the current study set out to investigate the mechanism of miR-140-5p in OA cartilage injury. Firstly, the murine and cell models of OA were established, and cartilage tissues of OA mice were observed using hematoxylin and eosin staining and safranin O staining. Chondrocyte pyroptosis was further assessed using immunohistochemical and Calcein-AM/PI staining. The levels of gasdermin-D (GSDMD)-N, cleaved caspase-1, interleukin (IL)-1ß, and IL-18 in cartilage tissues and cells were determined using Western blot and enzyme-linked immunosorbent assay kits. The targeting relationship between miR-140-5p and cathepsin B (CTSB) was verified using a dual-luciferase assay. Moreover, the binding of CTSB and Nod-like receptor protein 3 (NLRP3) was detected using co-immunoprecipitation assay. Lastly, the effects of NLRP3 activation and CTSB overexpression on chondrocyte pyroptosis were documented. It was found that OA induction aggravated cartilage tissue injury and enhanced chondrocyte pyroptosis. miR-140-5p was poorly-expressed in OA models, and miR-140-5p over-expression alleviated chondrocyte pyroptosis, as evidenced by decreased GSDMD-N, cleaved caspase-1, IL-1ß, and IL-18 levels. miR-140-5p targeted the CTSB gene, whereas CTSB further bound to NLRP3 and activated the NLRP3 inflammasome. Additionally, CTSB over-expression or NLRP3 activation reversed the inhibitory effect of miR-140-5p on chondrocyte pyroptosis. Collectively, our findings revealed that miR-140-5p repressed chondrocyte pyroptosis and alleviated OA cartilage injury via inhibition of the CTSB/NLRP3. This study may confer a theoretical basis for the treatment of OA cartilage injury.

Deep learning-based direction-of-arrival estimation for multiple speech sources using a small scale array.

A high resolution direction-of-arrival (DOA) approach is presented based on deep neural networks (DNNs) for multiple speech sources localization using a small scale array. First, three invariant features from the time-frequency spectrum of the input signal include generalized cross correlation (GCC) coefficients, GCC coefficients in the mel-scaled subband, and the combination of GCC coefficients and logarithmic mel spectrogram. Then the DNN labels are designed to fit the Gaussian distribution, which is similar to the spatial spectrum of the multiple signal classification. Finally, DOAs are predicted by performing peak detection on the DNN outputs, where the maximum values correspond to speech signals of interest. The DNN-based DOA estimation method outperforms the existing high resolution beamforming techniques in numerical simulations. The proposed framework implemented with a four-element microphone array can effectively localize multiple speech sources in an indoor environment.

Investigating starch gelatinization through Stokes vector resolved second harmonic generation microscopy.

The changes of the morphology during heating and the degree of crystallinity of dry and hydrated starch granules are investigated using second harmonic generation (SHG) based Stokes polarimetry. A spatial distribution of various polarization parameters, such as the degree of polarization (DOP), the degree of linear polarization (DOLP), and the degree of circular polarization (DOCP) are extracted and compared with the two dimensional second harmonic (SH) Stokes images of starch granules. The SH signal from hydrated and dry starch on heating differed significantly in DOLP and DOCP values, indicating that hydrated starch has a greater degree of ultrastructural amylopectin disorder. The detail of denaturation and the phase transition of hydrated starch demonstrate the significant influence of thermal processing.

[Evaluation indices of greenhouse gas mitigation technologies in cropland ecosystem].

In spite of the increasing studies on greenhouse gas (GHG) emissions mitigation technologies, there is still a lack of systematic indices for evaluation of their overall impacts in croplands. In this study, we collected all the indices relating to greenhouse gas emissions and analyzed each index following the principles of representativeness, objectivity, completeness, dominance and operability. Finally, we proposed evaluation indices for mitigation technologies based on the current situation of China. Crop yield per unit area was proposed as a constrained index, and greenhouse gas emissions intensity, defined as GHG emissions per unit of produced yield, was proposed as comprehensive index to evaluate the greenhouse effect of various croplands mitigation technologies. Calculation of GHG emissions intensity involved yield, change of soil organic carbon, direct N2O emissions, paddy CH4 emissions and direct and indirect emissions from inputs into croplands. By following these evaluation indices, the greenhouse effect of the technologies could be well evaluated, which could provide scientific basis for their further adoption.

Revealing molecular structure and orientation with Stokes vector resolved second harmonic generation microscopy.

We report on measurements and characterization of polarization properties of Second Harmonic (SH) signals using a four-channel photon counting based Stokes polarimeter. In this way, the critical polarization parameters can be obtained concurrently without the need of repeated image acquisition. The critical polarization parameters, including the degree of polarization (DOP), the degree of linear polarization (DOLP), and the degree of circular polarization (DOCP), are extracted from the reconstructed Stokes vector based SH images in a pixel-by-pixel manner. The measurements are further extended by varying the polarization states of the incident light and recording the resulting Stokes parameters of the SH signal. In turn this allows the molecular structure and orientation of the samples to be determined. Use of Stokes polarimetry is critical in determination of the full polarization state of light, and enables discrimination of material properties not possible with conventional crossed-polarized detection schemes. The combination of SHG microscopy and Stokes polarimeter hence makes a powerful tool to investigate the structural order of targeted specimens.

Stokes vector based polarization resolved second harmonic microscopy of starch granules.

We report on the measurement and analysis of the polarization state of second harmonic signals generated by starch granules, using a four-channel photon counting based Stokes-polarimeter. Various polarization parameters, such as the degree of polarization (DOP), the degree of linear polarization (DOLP), the degree of circular polarization (DOCP), and anisotropy are extracted from the 2D second harmonic Stokes images of starch granules. The concentric shell structure of a starch granule forms a natural photonic crystal structure. By integration over all the solid angle, it will allow very similar SHG quantum efficiency regardless of the angle or the states of incident polarization. Given type I phase matching and the concentric shell structure of a starch granule, one can easily infer the polarization states of the input beam from the resulting SH micrograph.

Correcting speckle contrast at small speckle size to enhance signal to noise ratio for laser speckle contrast imaging.

In laser speckle contrast imaging, it was usually suggested that speckle size should exceed two camera pixels to eliminate the spatial averaging effect. In this work, we show the benefit of enhancing signal to noise ratio by correcting the speckle contrast at small speckle size. Through simulations and experiments, we demonstrated that local speckle contrast, even at speckle size much smaller than one pixel size, can be corrected through dividing the original speckle contrast by the static speckle contrast. Moreover, we show a 50% higher signal to noise ratio of the speckle contrast image at speckle size below 0.5 pixel size than that at speckle size of two pixels. These results indicate the possibility of selecting a relatively large aperture to simultaneously ensure sufficient light intensity and high accuracy and signal to noise ratio, making the laser speckle contrast imaging more flexible.

Polarization-resolved second harmonic generation microscopy with a four-channel Stokes-polarimeter.

We developed a four-channel photon counting based Stokes-polarimeter for spatial characterization of polarization effects in second harmonic generation (SHG). We have implemented a calibration technique allowing quantitative measurement of polarization parameters, such as the degree of polarization (DOP), degree of linear polarization (DOLP), degree of circular polarization (DOCP), as well as anisotropy from the acquired Stokes parameters. The technique is used as contrast mechanism to characterize the polarization properties from two potassium dihydrogen phosphate (KDP) micro-crystals and collagen type-I in SHG microscopy.

Correcting the detrimental effects of nonuniform intensity distribution on fiber-transmitting laser speckle imaging of blood flow.

Laser speckle spatial contrast analysis (LSSCA) is superior to laser speckle temporal contrast analysis (LSTCA) in monitoring the fast change in blood flow due to its advantage of high temporal resolution. However, the application of LSSCA which is based on spatial statistics may be limited when there is nonuniform intensity distribution such as fiber-transmitting laser speckle imaging. In this study, we present a normalized laser speckle spatial contrast analysis (nLSSCA) to correct the detrimental effects of nonuniform intensity distribution on the spatial statistics. Through numerical simulation and phantom experiments, it is found that just ten frames of dynamic laser speckle images are sufficient for nLSSCA to achieve effective correction. Furthermore, nLSSCA has higher temporal resolution than LSTCA to respond the change in velocity. LSSCA, LSTCA and nLSSCA are all applied in the fiber-transmitting laser speckle imaging system to analyze the change of cortical blood flow (CBF) during cortical spreading depression (CSD) in rat cortex respectively, and the results suggest that nLSSCA can examine the change of CBF more accurately. For these advantages, nLSSCA could be a potential tool for fiber-transmitting/endoscopic laser speckle imaging.

Simultaneous automatic arteries-veins separation and cerebral blood flow imaging with single-wavelength laser speckle imaging.

Automatic separation of arteries and veins in optical cerebral cortex images is important in clinical practice and preclinical study. In this paper, a simple but effective automatic artery-vein separation method which utilizes single-wavelength coherent illumination is presented. This method is based on the relative temporal minimum reflectance analysis of laser speckle images. The validation is demonstrated with both theoretic simulations and experimental results applied to the rat cortex. Moreover, this method can be combined with laser speckle contrast analysis so that the artery-vein separation and blood flow imaging can be simultaneously obtained using the same raw laser speckle images data to enable more accurate analysis of changes of cerebral blood flow within different tissue compartments during functional activation, disease dynamic, and neurosurgery, which may broaden the applications of laser speckle imaging in biology and medicine.

Spatiotemporal laser speckle contrast analysis for blood flow imaging with maximized speckle contrast.

Laser speckle contrast imaging is a technique used for imaging blood flow without scanning. Though several studies have attempted to combine spatial and temporal statistics of laser speckle images for reducing image noise as well as preserving acceptable spatiotemporal resolution, the statistical accuracy of these spatiotemporal methods has not been thoroughly compared. Through numerical simulation and animal experiments, this study investigates the changes in the mean speckle contrast values and the relative noise of the speckle contrast images computed by these methods with various numbers of frames and spatial windows. The simulation results show that the maximum relative error of the mean speckle contrast computed by the spatiotemporal laser speckle contrast analysis (STLASCA) method, in which the speckle contrast images are computed by analyzing the 3-D spatiotemporal speckle image cube, is approximately 5%, while it is higher than 13% for other methods. Changes in the mean speckle contrast values and the relative noise computed by these methods for animal experiment data are consistent with the simulation results. Our results demonstrate that STLASCA achieves more accurate speckle contrast, and suggest that STLASCA most effectively utilizes the number of pixels, thus achieving maximized speckle contrast, and thereby maximizing the variation of the laser speckle contrast image.

[Application of DNDC model in estimating cropland nitrate leaching].

The leaching amount of soil water and nitrate from winter wheat field under typical planting system in Jinan City of Shandong Province was measured with lysimeter during the whole growth season in 2008, and the feasibility of applying DNDC model to estimate this leaching amount was tested by the obtained data. On the whole, DNDC model could better simulate the soil water movement in the crop field, with the accuracy being acceptable. However, there existed definite deviation in the simulation of nitrate leaching. The simulated value (18.35 kg N x hm(-2)) was 3.46 kg N x hm(-2) higher than the observed value (14.89 kg N x hm(-2)), with a relative error of about 20%, which suggested that some related parameters were required to be further modified. The sensitivity test of DNDC model showed that cropland nitrate leaching was easily to be affected by irrigation and fertilization. It was proved that the model had definite applicability in the study area.

[Clinical study on PRP in improving bone repair].

OBJECTIVE: To investigate the effect of PRP in improving bone repair so as to provide an experimental basis for repairing bone defect. METHODS: From January 2007 to March 2007, 59 cases of fresh fracture were treated with PRP (PRP group, n=29) and with conventional open reduction and fixation (control group, n=30). In PRP group, there were 19 males and 10 females, aging 18-57 years (mean 43.62 years), including 8 cases of femoral fracture, 12 cases of tibio-fibula fracture, cases of humeral fracture, 3 cases of ulna and radia fracture, 2 cases of fracture in extremity and 2 cases of clavicular fracture. In control group, there 19 males and 11 females, aging 22 to 57 years (mean 35 years), and including 7 cases of femoral fracture, cases of tibio-fibula fracture, 5 cases of humeral fracture, 7 cases of ulna and radia fracture, 1 case of fracture in extremity and 1 case of clavicular fracture. All patients were admission within 24 hours after injury. The time from hospitalization to operation was 24 to 48 hours (mean 36 hours). There were no statistically significant differences in the common data between two groups (P > 0.05). The degree of inflammatory reaction of wounds, the grade of wounds healing and the hospitalization days were observed and analysed statistically. RESULTS: At 5 days after operation, no inflammatory reaction was observed in 22 cases of RPR group and in 17 cases of control group, mild inflammatory reaction in 6 cases of RPR group and in 8 cases of control group, moderate inflammatory reaction in 1 case of RPR group and in 3 cases of control group, and serious inflammatory reaction in 2 case of control group, showing no statistically significant differences (P > 0.05). Wound healed by first intention in 29 patients of RPR group and in 29 patients of control group (29/30), by second intention after 3 days of dressing change in 1 patient of control group; showing no statistically significant differences (P > 0.05). The hospitalization days were (8.21 +/- 1.52) days in RPR group and (11.67 +/- 1.48) days in control group, showing statistically significant differences (P < 0.05). All patients of two groups were followed up 6-12 months (mean 10 months). The X-ray films at follow-up showed that bony healing was achieved within 6-8 months in RPR group and within 8-10 months in control group, showing no statistically significant differences (P > 0.05). CONCLUSION: Using PRP can speed up the healing of operative incision with no adverse effect, shorten the hospitalization days.

In vivo study effect of particulate Bioglass in the prevention of infection in open fracture fixation.

There are many in vitro experiments showing that particulate bioactive glasses have a broad and certain antibacterial effect, but there is no report about this antibacterial effect in vivo so far. The aim of this study is to examine the efficacy of particulate Bioglass in reducing the rate of infection with Staphylococcus aureus after the fixation of open tibial fractures in rabbits. The test in vivo was carried out with male rabbits split into two groups infected with Staphylococcus aureus at the right tibial fracture sites fixed with plate and screw, either with or without bioactive glass respectively. Culture results show that six of ten rabbits from the control group had a positive culture for the strain of Staphylococcus aureus ATCC25923, compared with six of the nine rabbits from the Bioglass group. The median radiographic score is 4.5 points for the rabbits from the control group and 4 points for the rabbits from the Bioglass group. The median histopathological score was 2.5 points for the rabbits in the control group and 3 points for the rabbits in the Bioglass group. In conclusion, this study showed no significant difference between the rates of infection of two groups. Particulate Bioglass did not reduce the rate of infection with Staphylococcus aureus after the fixation of open tibial fractures in rabbits.

[Follow-up study on platelet-rich plasma in repairing chronic wound nonunion of lower limbs in 47 cases].

OBJECTIVE: To study the effect of platelet-rich plasma (PRP) on repairing chronic wounds of lower limbs. METHODS: From May 2007 to November 2007, 47 patients suffering from chronic wounds of lower limbs were treated. There were 41 males and 6 females, aged from 15 to 68 years (43.2 years on average). The disease was caused by tibiofibular fracture in 20 cases, calcaneus fracture in 4 cases, metatarsal fracture in 1 case, multiple open fracture of lower limbs in 3 cases, tibia osteomyelitis in 10 cases, femur osteomyelitis in 1 case, soft tissue injury of ankle in 4 cases, infection after amputation in 2 cases, infection after foot orthomorphia in 1 case, and infection after calcaneus tendon neoplasia in 1 case. Their chronic wounds did not healed after 2 to 4 months of therapy. Among them, chronic wounds complicated with fracture nonunion in 23 cases and positive bacterial culture result in 38 cases. Debridement and autogenous PRP gel injection were applied every 2 months and for twice. RESULTS: The patients were followed up for 4 months after the first PRP injection. Two months after the first PRP injection, chronic wounds contracted significantly in 34 patients with purulence and necrosis tissue cleaned up, circulation of soft tissue improved and exposed bone or muscle tissue covered by neurogenetic granulation. No patient was completely cured. Two months after the second PRP injection, the average coverage rate was 79.3% +/- 18.0%, the total cure rate was 29.8%. The volume of the chronic wounds decreased by (9.3 +/- 4.9) mL after PRP therapy (2.5 +/- 2.7) mL when compared with (11.8 +/- 5.6) mL of before therapy, showing significant difference (P < 0.05). X-ray photograph showed that among the 23 cases of fracture nonunion, fracture healed completely in 9 cases; bony callus formation increased obviously in 12 cases; no significant change was observed in 2 cases. No aggravated sign of osteomyelitis was notified. Positive results of bacterial culture reduced to 15 cases. CONCLUSION: PRP efficiently enhances the recovery of soft tissue defect and speeds up the chronic wounds healing of lower limbs.