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Background Previous articles have focused on the diagnosis and treatment of acute hematogenous osteomyelitis. Here, we present a case of chronic hematogenous osteomyelitis in a 2-month-old girl. The diagnostic procedure was unusual and difficult due to negative culture results. Case presentation A girl aged 2 months and 23 days had fever and swelling in her right lower leg for 7 days. On the basis of her medical history, physical, and histological examination results; and radiologic and magnetic resonance imaging findings, a diagnosis of chronic osteomyelitis was made. The patient underwent surgical treatment and was discharged successfully. The patient showed good recovery and no sequelae at the 12-month follow-up. Conclusion Hematogenous osteomyelitis in babyhood is different from that at any other age. Hematogenous osteomyelitis-related bone destruction in babyhood is more serious and occurs faster. The transition from acute hematogenous osteomyelitis to chronic hematogenous osteomyelitis takes only 7 days. To the best of our knowledge, this chronic hematogenous osteomyelitis patient is the youngest ever reported.

Objective: The present study aims to assess the willingness to pay (WTP) for and willingness to vaccinate (WTV) with the Coronavirus (COVID-19) vaccine booster dose in China when the pandemic is under adequate control and the majority of the population is vaccinated. This study is also to identify significant factors associated with the WTP.Methods: This was a cross-sectional study on adults with no past or present COVID-19 infection. An online questionnaire was distributed to collect data on vaccination status, quarantine experience, and factors related to health beliefs on vaccination. The WTV was assessed through the vaccination preference. The WTP was examined by payment scale (PS) and iterative bidding game (IBG) administered in random order. Three IBG algorithms with different starting-price were presented randomly. The average WTP of PS and IBG were analyzed as primary outcomes using univariate and multivariate analyses. Multivariate ordered logistic regression was performed to identify significant factors for the WTP.Results: The survey recruited 543 participants with a mean age of 32 years and 57.80% being female. The WTV rate was 86.74%, while 94.66% of participants completed full-schedule or enhanced vaccination. The mean WTP was CNY 149 (±CNY 197) and the median WTP was CNY 80. Regarding significant factors for the WTP, urban residents were 57% more likely (95% CI: 1.11-2.22) to pay for a high-priced vaccine than rural residents. Respondents who completed full-schedule vaccination were 46% more likely (95% CI: 1.03–2.07) to pay for a high-priced vaccine than those who completed enhanced vaccination. Respondents with a low household income of CNY 40k or lower were 62% less likely (95% CI: 0.21–0.66) to pay for a high-priced vaccine than those with a middle household income of CNY 110k–210k. Other significant factors associated with the WTP included the perceived benefit of vaccination and peer environmental pressure in the health belief model.Conclusion: The WTV with the COVID-19 vaccine booster dose was high in China. The WTP was influenced by the place of residence, vaccination status, household income, perceived benefit of vaccination, and environmental peer pressure. Study findings can inform policymakers to better design vaccination programs and financial schemes involving out-of-pocket payments.

Background. The screw and cement technique is a convenient method used to rebuild medial tibial plateau defects in primary total knee arthroplasty (TKA). The objective of this study was to perform a finite element assessment to determine the effect of different numbers of screws on the stability of TKA and to determine whether differences exist between two different insertion angles. Method. Six tibial finite element models with defects filled with screws and cement and one model with defects filled only with cement were generated. Contact stresses on the surface of cancellous bone in different areas were calculated. Results. Compared to the cement-only technique, the stress on the border of cancellous bone and bone cement decreased by 10% using the screw and cement technique. For bone defects with a 12% defect area and a 12-mm defect depth, the use of 1 screw achieved the greatest stability; for those with a 15% defect area and a 20-mm defect depth, 2 screws achieved the greatest stability. Conclusions. (1) The screw and cement technique is superior to the bone cement-only technique. For tibial defects in which the defect area comprises a large percentage but the depth is less than 5 mm, the screw and cement technique is recommended. (2) Vertical screws can achieve better stability than oblique screws. (3) Screws should be used in moderation for different defects; more is not always better.

BACKGROUND Hepatitis C virus (HCV) infection is an important health threat in China to which direct acting antivirals (DAAs) are very effective. In 2019, another novel DAA glecaprevir/pibrentasvir (GLE/PIB) was officially approved. Knowledge of its cost-effectiveness would be informative for clinical decision-making but has not been evaluated. This study aims to evaluate the cost-effectiveness of GLE/PIB to inform policy-making on drug reimbursement and HCV eradication. METHODS Markov models were developed from the payers' perspective and simulated the lifetime experience of adult patients chronically infected with HCV genotype 1 or genotype 2. Two regimens, GLE/PIB and pegylated interferon (pegIFN) plus ribavirin (RBV), were compared in cost and quality adjusted life years (QALY) with both outcomes being discounted to 2020 values. The incremental cost-effectiveness ratio (ICER) was computed to reflect the incremental benefit of GLE/PIB versus pegIFN + RBV. The robustness of the model outcomes was examined using deterministic and probabilistic sensitivity analysis (PSA) to identify influential parameters and to assess the probability of GLE/PIB being cost-effective. The GDP per capita in China in 2019 ($10,275) was used as the threshold for cost-effectiveness. RESULTS For the entire target population, GLE/PIB was the dominant regimen attaining a cost-saving of $255 and 1.17 more QALYs relative to pegIFN + RBV. The finding was more pronounced for HCV genotype 1 infection by saving $1,656 and creating 1.37 more QALYs. At the $10,275 threshold, the probability of GLE/PIB being cost-effective was 99.32% overall and 99.85% for HCV genotype 1 infection. The age of starting DAA treatment, price of pegIFN + RBV, cost of cirrhosis treatment and duration of the GLE/PIB regimen were the five most influential factors. For the patients with HCV genotype 2 infection, the ICER of GLE/PIB was $12,914/QALY with 95% confidence interval of $4,047/QALY to $37,640/QALY. The GLE/PIB regimen statistically cannot be ruled out as a cost-effective option for HCV genotype 2 infection. CONCLUSIONS GLE/PIB is a cost-effective strategy to treat chronic HCV genotype 1 and HCV genotype 2 infection in China. This regimen should be initiated at a younger age to maximize its value. To achieve national eradication, it may be timely to consider replacing pegIFN + RBV with DAAs, such as GLE/PIB, as the first-line treatment.

BackgroundThe curative effect of antibiotic-impregnated Calcium Sulfate in pediatric ostemyelitis is unknown. The purpose of this study was to compare the outcomes of two treatment methods, decompression combined with antibiotic-impregnated calcium sulfate and decompression alone, for the treatment of pediatric Hemotogenous Osteomyelitis.MethodsBetween 2013 to 2016, forty-one patients with Hematogenous Osteomyelitis met the criteria were included for assessment. Twenty-one patients were included in the calcium sulfate group (the CS group) in which vancomycin and/or gentamicin impregnated calcium sulfate was used as an adjuvant after bone decompression while 20 patients as the control group were undergone bone decompression alone. The infection recurrence rate, hospital stay, wound healing duration, serum inflammatory index, pathological fracture, leakage of the incision ,follow-up time were compared between the two groups.ResultsInfection recurrence was 0% (0/21) in CS group and 15%(3/20) in control group within 12 months(P=0.107). Infection recurrence was 0%(21/21) in CS group and 20% (16/20) of patients at a minimum of 24(range 24 to 67) months follow-up(P=0.048). Mean hospital stay were 8.19(range 3 to 21) days in CS group and 15.95(range 5 to 47) days in control group(P=0.02). Mean wound healing duration were 16.1(range 10 to 29) days in CS group and 15.5(range 10 to 25) days in control group(P=0.65). Serum inflammatory index for WBC(White Blood Cells), ESR( Sedimentation Rate), CRP(C-Reactive Protein) was respectively 8.76(6.03-12.07)*10^9/L, 44.14(26-70)mm/L, 12.35(1.03-35.04) mg/Lin CS group and 8.90(5.68-13.56)*10^9/L, 39.25(19-57)mm/L, 15.65(1.02-45.69) mg/L in control group(P=0.82, P=0.31, P=0.51). Pathological fracture was 0% (0/21) in CS group and 10%(2/20) in control group(P=0.23). Leakage of the incision was 4.76% (0/21) in CS group and 10%(2/20) in control group(P=0.61). ConclusionsAntibiotic-impregnated Calcium Sulfate can reduce infection recurrence and shorten the mean hospital stay in pediatric Hemotogenous Osteomyelitis. The curative effect of antibiotic-impregnated Calcium Sulfate in pediatric ostemyelitis is satisfactory. Trial registrationRetrospectively registered.

The “classical pattern” of stock price formation has long been widely used in the determination of future price trends of stocks, and the identification and analysis of classical price patterns have an important guiding role in investors’ decision-making and trading. The wavelet transform is a useful tool to remove some of the noise of time series because it has the characteristic of multiresolution. In this study, we propose a method for stock price pattern recognition based on the wavelet transform and dynamic time warp (DTW). A pattern recognition method with similar quantified results is developed to obtain accurate pattern recognition results. That is, using the wavelet transform to smooth the original price graph, and then using the DTW algorithm improved in this study to find the graph with the smallest distance from the target graph under the sliding window method, the identification and analysis of the target graph can be realized. In order to improve the recognition rate of the target graph, we preprocessed the raw price sequence using the moving average convergence and divergence (MACD) algorithm based on the control experiments set up in this study. The pattern recognition method used in this study will identify the price patterns of a certain time window as a whole, thus avoiding the problem of how to objectively select the important points that constitute a price pattern and the mathematical definition of different price patterns in the previous traditional methods.

Investigation on penetration into concrete targets is of great importance as concrete is widely used as the fundamental construction material. To achieve a more accurate prediction of penetration depths of concrete targets, a further study was conducted to explore the entrance effect by using AUTODYN hydrocode in this study. The numerical results on both deceleration-time history and depth of penetration of projectiles are in good agreement with experimental data, which demonstrate the feasibility of the numerical model in these conditions. A new target model was established with a predrilled hole around the symmetry axis to simulate the entrance effect of the crater phase on the penetration process. Compared with the regular target, the predrilled target enters the peak of acceleration earlier, leading to the reduction of the depth of penetration. In addition, simulation results indicated that nose shape significantly influenced crater region depth, while the depth was independent of the impact velocity and the target strength. Based on the simulation of entrance effect, a modified formula of penetration depth has been proposed and validated in terms of different nose shapes. The crater region depths obtained from the simulations can improve the accuracy of the predictions of the penetration depths for the penetration of concrete targets.

To discuss the relationship between matric suction and strength under different drying-wetting cycle paths of residual clay, soil water characteristic curve was determined by the filter paper method. The shear strength, unconfined compressive strength and matric suction were obtained during desorption and adsorption at the drying and wetting cycle. The experimental results show that the matric suction of soil specimens subjected to different drying and wetting cycle paths are different although at the same water content. Contributions of internal friction angle and cohesion to shear strength are different at different matric suction. In the low matric suction stage, matric suction mainly contribute to shear strength by affecting the cohesion, yet in the high matric suction stage by increasing both the internal friction angle and cohesion; in the transition matric suction stage, the contribution of cohesion decreases while the contribution of internal friction angle increases. Furthermore, the unconfined compressive strength of specimens subjected to the drying and wetting cycle path of desorption first and then adsorption is reduced and increase with the opposite path.

Objectives: To measure and compare the included angle between the surgical transepicondylar axis (STEA) and the posterior condylar line (PCL) and the included angle between the femoral anteroposterior line (APL) and PCL, and to discuss the value of STEA, APL, and PCL as rotational alignment landmarks of the distal femur in total knee arthroplasty (TKA). Methods: Seventy-five normal femoral specimens from Chinese adult cadavers were randomly selected. An axial photograph of every femoral specimen was taken with a digital camera and put into a personal computer. Using Photoshop 7.0.1 software, the included angle between the perpendicular line of APL and the PCL, noted as APA, together with the posterior condylar angle (PCA) between STEA and PCL were measured and compared using a paired-samples t-test. Results: The value for PCA was 3.67°± 1.62° (range, 0.75°–5.90°) and for APA 3.50°± 1.40° (range, 1.34°–5.65°). There was no significant difference between these two angles (t= 0.949, P= 0.359). Considering their relatively small means, these two angles showed wide variations. Conclusions: The rotational alignment of the femoral component can not accurately be determined by using PCL as a landmark. In order to get a proper rotational alignment of the femoral component in most cases of TKA, APL and STEA should be used as a double check.

To evaluate perioperative occult blood loss following total knee arthroplasty (TKA).A retrospective analysis of 40 patients undergoing TKA was conducted to calculate the mean blood loss and occult blood loss according to Gross formula.The mean total blood loss was 1538 ml in these cases with occult blood loss of 791 ml. In patients with autologous blood transfusion, the mean total blood loss was 1650 ml with occult blood loss of 786 ml. In patients without autologous blood transfusion, the mean total blood loss was 1370 ml with occult loss of 798 ml.TKA often results in large volume of occult blood loss in the perioperative period which can not be fully compensated by autologous blood transfusion, and additional blood supply is needed for maintenance of the circulating volume.

To study the rotation of femoral component and tibial component with CT and evaluate the relationship between patellofemoral complications and rotational alignment of the components.Thirty patients with isolated patellofemoral complications after total knee arthroplasty were compared with 20 patients with well functioning total knee replacements free of patellofemoral complications. The epicondylar axis and tibial tubercle were used as references on CT scans to quantify the rotational alignment of the femoral and tibial components.Patients with patellofemoral complications had excessive combined (tibial plus femoral) internal component rotation, which was directly proportional to the severity of the patellofemoral complications. Mild combined internal rotation (1 degree-4 degrees) was correlated with patellar and lateral tracking tilting, moderate rotation (3 degrees-8 degrees) with patellar subluxation, and severe rotation (7 degrees-17 degrees) with early patellar dislocation or late patellar prosthesis failure. The control group had combined external rotation of 10 degrees-0 degree.The direct correlation of combined internal component rotation to the severity of the patellofemoral complication suggests that internal component rotation may be the predominant cause of patellofemoral complications in patients with normal axis alignment. CT scans can be used intraoperatively and postoperatively to determine whether the rotational malalignment is present to require revision of one or both components.

To investigate the ultrastructural changes of the mitochondria in the skeletal muscle cells of rats subjected to repeated exhausting exercises on treadmill and the protective effect of oral vitamin E.Thirty male SD rats were randomized into control group (n=10), exhausting exercise group (n=10) and exhausting exercise group with oral vitamin E treatment (n=10), with the latter two groups taking repeated exhausting running exercises on the treadmill in a course of 4 weeks. At the end of the course of exercises, the rats were sacrificed and the quadriceps femoris muscles isolated for observation the ultrastructures of the skeletal muscle cells by transmission electron microscope (TEM).After 4-week exhausting exercises, the myofilaments of the skeletal muscle were seen in disordered alignment, and the mitochondria exhibited abnormal morphological changes of swelling and vacuolar degeneration. In vitamin E-treated rats also undertaking the exercise, the ultrastructures of the skeletal muscle cells were almost normal as compared with the normal control group.Vitamin E can protect the function of the skeletal muscle mitochondria of rats taking repeated exhausting exercises.

To investigate the effect of antioxidant vitamins (vitamin E and vitamin C) on the exercise performance of rats.Fifty male SD rats were randomly divided into control group (C), exhausting exercise control group (E), vitamin E group (M1), vitamin C group (M2) and vitamin E plus vitamin C group (M3). The rats in the exercising groups (E, M1, M2, M3) were propelled for repeated exhausting runs on the treadmill for 4 weeks.Exclusive use of oral vitamin E or in combination with vitamin C significantly improved the body mass, total exercise treadmill length and net mass of rat quadriceps femoris after the 4-week exercise. No difference was noted between the rats taking oral vitamin C or E alone. The rats in M1, M2 and M3 groups had lower malondialdehyde (MDA) and free calcium content in the quadriceps femoris than the control rats, and SOD activities in the quadriceps femoris mitochondria of rats in the former 3 groups were significantly higher than those of the control group.Vitamin E can protect the mitochondria in the skeletal muscles and improve the exercise performance of rats, the effect of which can be enhanced by vitamin C, but vitamin C alone can not sufficiently achieve the effects.

The multibody contact problem is solved by the penalty finite element method in which the noninterference conditions are defined as a penalty term. The static condensation is applied in the calculation. Using the recurrent regularities mentioned in the paper one can directly obtain the governing equation for any body-contact system, and it is easy to develop a computer program. Because the iterative procedure is only related to the node displacements and not to the node forces, the computing time is reduced accordingly. The load distribution in the roller bearing is calculated and the calculated result agrees well with the test. Further, the method is used in the optimization of a multibody contact system with roller bearing.