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Objective To investigate the influence of preoperative lipids and glucose on the postoperative recovery of patients undergoing total knee arthroplasty (TKA) for knee osteoarthritis (KOA). Methods Clinical data were collected from 492 patients with KOA who were hospitalized and underwent surgical treatment in Department of Joint Surgery, The Affiliated Hospital of Qingdao University, from January 2021 to January 2022, including general clinical data and related blood biochemical para-meters in the fasting state before surgery. American Knee Society (AKS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were recorded for the patients at six months after surgery, and WOMAC score 35 was considered poor postoperative recovery; AKS score >70 was consi-dered good postoperative recovery, and AKS score

Exploring the response of leaf anatomical structure to climate warming is helpful for understanding the adaptive mechanisms of trees to climate change. We conducted a warming experiment by transplanting seedlings of Larix gmelinii from 11 provenances to two common gardens, and examined the response of leaf anatomical structure to climate warming. The results showed that warming significantly increased leaf thickness ( TL), upper epidermal mesophyll thickness ( TUEM), lower epidermal mesophyll thickness (TLEM), endodermal thickness ( TE ), vascular bundle diameter ( DVB), transfer tissue thickness (Ttt), and the percentage of mesophyll thickness to TL (PMT), and significantly decreased the upper epidermal thickness ( TUE) and the percentage of epidermal thickness to TL ( PE). The mesophyll thickness was positively associated with chlorophyll concentration and maximum net photosyn-thetic rate. The responses of TL, TUEM, TLEM, TE, DVB, TTT, TUE, PMT and PE to warming differed among all the provenances. As the aridity index of the original site increased, the magnitude of the warming treatment' s effect decreased for TL, TUEM, TLEM, TTT and PMT, and increased for TUE and PE. Warming increased the thickness and proportion of profit tissue (e.g., mesophyll) and decreased the thickness and proportion of defensive tissue (e.g., epidermis), and those changes varied among provenances. L. gmelinii could adapt to climate warming by adjusting leaf anatomical structure, and this ability was weak for trees from provenance with high aridity index. [ABSTRACT FROM AUTHOR]

Unified power flow controller(UPFC) is the most advance flexible ac transmission system(FACTS). Active/reactive power balance for UPFC is analyzed in this paper when it is working in power flow control mode, and an improved real time power coordinate control strategy is proposed in paper. In the parallel converter control loops, an improved real-time dynamic feed forward method is added to reduce over voltage caused by imbalance power. The results of hardware-in-loop simulation based RT-LAB platform show that this new coordinate control strategy，comparing with the conventional one, can decrease excessive voltage excursions of the send terminal ac voltage and DC-link voltage and improve the control performance during power flow changing or system occurring fault.

Aiming at the problems of the ring oscillator such as large power consumption, loud noise, linearity deficiency etc., a novel ring oscillator with cross feed forward structure is proposed based on TSMC 55 nm process. After the contribution percentage of device thermal noise and flicker noise on the output phase noise is analyzed, the capacitance filtering technique is applied to reduce the output phase noise. The linear current is obtained with the source negative feedback circuit to improve the linearity of the frequency modulation, and offers a wide tuning range.The Spectre RF simulation results show that the designed ring oscillator has a frequency coverage of 0.2 GHz～3.8 GHz, produces 8 phases. Its phase noise is -91.34 dBc/Hz@1 MHz, and the current consumption is 4.6 mA at the 1.2 V supply voltage. The results also indicate the good linearity.

Objective: To compare the early effectiveness between by anterior approach via Bikini incision and by OCM approach in the primary total hip arthroplasty (THA)., Methods: Between June 2015 and March 2016, 60 patients with ischemic necrosis of the femoral head who accorded with the inclusion criteria were chosen in the study, who were divided into 2 groups according to different surgical approaches. THA was performed on 30 patients by anterior approach via Bikini incision (group A), and on 30 patients by OCM approach (group B). There was no significant difference in age, gender, body mass index, side of affected hip, Steinberg stage of ischemic necrosis of femoral head, preoperative hemoglobin, preoperative Harris score, and preoperative visual analogue scale (VAS) between 2 groups ( P >0.05). The operation time, length of incision, intraoperative blood loss, transfusion rate, starting time of straight leg raising exercise, starting time of active abduction of hip, hospitalization time, the incidence of limb length discrepancy, postoperative Harris score and VAS score were recorded and compared between 2 groups. Anteroposterior pelvic X-ray films were taken to measure acetabular abduction and acetabular anteversion., Results: Primary healing of incision was obtained in all patients of 2 groups, and there was no significant difference in complication between 2 groups ( χ 2 =0.144， P =0.704). All the patients of 2 groups were followed up 3 to 12 months, averaged 6 months. There was no significant difference in operation time, length of incision, intraoperative blood loss, transfusion rate, hospitalization time, and starting time of straight leg raising exercise between 2 groups ( P >0.05). Group A was significantly shorter than group B in starting time of active abduction of hip ( t =-4.591, P =0.000), and was significantly lower than group B in the incidence of limb length discrepancy ( χ 2 =5.455, P =0.020). After operation, neither Harris score at 2 weeks, 6 weeks, 3 months, and 6 months nor VSA score at 24 hours and 6 weeks showed significant difference between 2 groups ( P >0.05). The anteroposterior pelvic X-ray films showed that all the prostheses were in good position, and there was no femoral prosthesis subsidence, acetabular cup displacement or dislocation. No significant difference was found in acetabular abduction and acetabular anteversion at 2 days after operation between 2 groups ( t =0.887, P =0.379; t =0.652, P =0.517)., Conclusion: Both of two approaches in THA can avoid muscle damage and achieve favorable short-term effectiveness. But, anterior approach via Bikini incision is superior to OCM approach in starting time of active abduction of hip and the incidence of limb length discrepancy.

Objective: To compare the clinical results of mobile-bearing and fixed-bearing prostheses in total knee arthroplasty (TKA) during 10 years follow-up so as to provide a reference for clinical selection of TKA prosthesis., Methods: Between January 2002 and December 2005, 113 patients with osteoarthritis of the knee joint underwent primary TKA, and the clinical data were retrospectively analyzed. Mobile-bearing prosthesis was used in 47 cases (group A) and fixed-bearing prosthesis in 66 cases (group B). There was no significant difference in age, gender, body mass index, varus and flexion deformity of the knee, range of motion (ROM) of the knee, knee society score (KSS), and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) between 2 groups before operation ( P >0.05), so the data were comparable., Results: The operation time of groups A and B was (88.1±6.5) and (90.3±7.2) minutes respectively, showing no significant difference ( t =1.666, P =0.099). The wounds healed by first intention in all patients of both groups, and no postoperative early complications of incision infection and deep venous thrombosis occurred. The follow-up time was 10.2-12.3 years (mean, 10.8 years) in group A, and was 10.2-12.6 years (mean, 11.3 years) in group B. Revision was performed in 3 cases of group A and 4 cases of group B; the survival rates of prosthesis were 93.6% and 93.9% in groups A and B respectively, showing no significant difference ( χ 2 =0.005, P =0.944). The postoperative knee ROM, KSS score, and WOMAC score were significantly improved when compared with preoperative ones ( P <0.05). The knee ROM and KSS score of group B were significantly better than those of group A at 6 weeks after operation ( P <0.05), but no significant difference was found between 2 groups at 1, 3, and 10 years after operation ( P >0.05). The WOMAC score of group A was significantly better than that of group B at 10 years after operation ( t =2.086, P =0.037), but no significant difference was shown at 6 weeks, 1 year, and 3 years after operation ( P >0.05). At 10 years after operation, the excellent and good rate of KSS score was 87.2% in group A and was 84.8% in group B, showing no significant difference ( χ 2 =0.018, P =0.893)., Conclusion: Good medium- and long-term clinical results can be achieved in TKA with both mobile-bearing and fixed-bearing prostheses. The TKA with fixed-bearing prosthesis is relatively simple with better early effectiveness of rehabilitation; and the TKA with mobile-bearing prosthesis could provide better long-term degree of satisfaction in WOMAC score, but a higher surgical skill and soft tissue balance techniques are needed.

Objective: To observe the effect of lentivirus-mediated cyclooxygenase 2 (COX-2) and Aggrecanase-1 silencing and insulin-like growth factor 1 (IGF-1) in BMSCs after injecting into the knee joint cavity in cynomolgus monkeys with knee osteoarthritis (OA)., Methods: BMSCs were isolated from the bone marrow of 10 donors. The lentivirus vector expressing genes of COX-2, Aggrecanase-1, and IGF-1 were constructed, and transfected into the third generation human BMSCs at 40 multiplicity of infection (virus group); BMSCs transfected with lentivirus-empty vector served as blank-virus group. The growth status and number of BMSCs were observed under inverted phase contrast microscope, and normal BMSCs were used as normal control group. At 1 week after transfected, the mRNA expressions of COX-2, Aggrecanase-1, and IGF-1 were detected with RT-PCR. Nine 3-year-old cynomolgus monkeys were selected to establish the OA model according to Hulth modeling method, and were randomly divided into 3 groups ( n =3). At 6 weeks after remodeling, the right knee joint cavity was injected accordingly with 1 mL BMSCs (about 1×10 7 cells) in virus group and blank-virus group, with 1 mL of normal saline in the blank control group; the left knee served as normal controls. The general condition was observed after injection; at 1, 4, and 6 weeks, the concentrations of prostaglandin E2 (PGE2), IL-1, Aggrecanase-1, and IGF-1 of double knee liquid were detected with ELISA; at 6 weeks, MRI, general observation, histology method, and immunohistochemistry method were used to detect the knee cartilage changes and the expressions of COX-2, Aggrecanase-1, and IGF-1 were measured with RT-PCR., Results: No significant difference was found in cell morphology and growth curve between 2 groups after transfection. By RT-PCR, COX-2, and Aggrecanase-1 expressions were significantly reduced, IGF-1 expression was significantly increased in virus group when compared with normal control group and the blank-virus group ( P <0.05). All monkeys survived to the end of the experiment after injection. When compared with blank-virus group and blank control group, the concentrations of PGE2, Aggrecanase-1, and IL-1 significantly decreased and the concentration of IGF-1 significantly increased in the virus group ( P <0.05), but the indicators in 3 groups were significantly higher than those in the normal control group ( P <0.05). MRI showed that abnormal articular surface with high density could be found in virus group, blank-virus group, and blank control group, while the virus group had the minimum area. Gross observation and histological observation showed that the cartilage morphology of virus group, blank-virus group, and blank control group was accordance with early OA articular cartilage changes, but virus group was better than blank-virus group and blank control group in repair degree, whose improved Pineda score was significantly lower ( P <0.05). Immunohistochemical staining showed that the virus group had deeper dyeing with occasional brown particles and more chondrocytes than blank-virus group and blank control group. By RT-PCR, COX-2 and Aggrecanase-1 mRNA expressions of cartilage in virus group were significantly decreased, and IGF-1 expression was significantly increased when compared with blank control group and the blank-virus group ( P <0.05)., Conclusions: Lentivirus-mediated multi-genes co-transfection in BMSCs can inhibit the expressions of COX-2 mRNA and Aggrecanase-1 mRNA, and enhance the IGF-1 mRNA expression, which decreases the concentration of inflammatory factors, and protects the joint cartilage effectively.

Objective: To explore the effects of astragalus (AST) , total flavone of astragalus (TFA), total saponins of astragalus (TSA) and astragalus polysaccharides (APS) on ischemia/reperfusion (40 min/60 min) injury in isolated guinea-pig heart., Methods: Isolated guinea-pig hearts underwent ischemia, then followed by K-H perfusion (I/R group), AST (60 mg/L),AST (60 mg/L), TFA (60 mg/L), TSA (60 mg/L) and APS (60 mg/L) perfusion (n = 6 each).Isolated hearts without ischemia serve as control group (n = 6). Activity of lactate dehydrogenas (LDH) and creatine kinase (CK) in effluent were measured.Infarct size, myocardial superoxide dismutase (SOD) activity and malondiadehyde (MDA) contents were also determined., Results: Compared to control hearts, heart rate, coronary flow and myocardial superoxide dismutase (SOD) activity were significantly reduced, while LDH and CK in effluent as well as myocardial MDA were significantly increased in the I/R hearts during reperfusion (all P < 0.05), these changes could be partly reversed by AST and TFA perfusion.Infarct size was also significantly reduced in AST (11.9 ± 2.03) % and TFA (13.31 ± 1.17) % treated hearts compared to that in I/R group (18.9 ± 2.27) % (all P < 0.01)., Conclusions: The findings indicate that AST and TFA could attenuate I/R injury in isolated guinea-pig heart possibly through enhancing the activity of SOD and reducing lipid peroxidation.

Objective: To investigate the effectiveness of mosaicplasty in repair of large-sized osteochondral compound defects and the integrity of transplanted tissue with recipient sites so as to lay a foundation for clinical application., Methods: Twenty-four adult goats were divided into 3 groups randomly. The diameters of defect were 6 mm for the medium-sized defects and 9 mm for the large-sized defects, which were created by a trepan. All of the defects were repaired with osteochondral plugs in diameters of 2 mm (the medium-sized defects) or 3 mm (the large-sized defects). The osteochondral plugs were harvested around the intercondylar fossa or intertrochlea groove, and pressed into the recipient sites by specialized instruments in a mosaic mode. No internal fixation was needed and the animal were allowed to move freely after operation. From 4 to 24 weeks postoperatively, the specimens were observed in gross and under electromicroscopy. X-ray detection and glycosaminoglycan (GAG) analysis were also performed to testify the healing process and the integrity of the cartilage and subchondral bone., Results: The transplanted subchondral bone was integrated firmly with each other or with recipient sites in both mosaicplasty groups. But 24 weeks postoperatively, transplanted cartilage was not integrate with each other apparently. Obvious cleavage between cartilage plugs could be seen. But in the large-sized defect groups, some of the osteochondral plugs were relapsed into the defects leaving the recipient sites some steps, leading to some degree of abrasion in the opposing articular cartilage. There was no significant difference in the GAG content between the transplanted cartilage and normal cartilage. X-ray analysis also demonstrated the healing process between the subchondral bone., Conclusion: Mosaicplasty can repair the medium or small-sized osteochondral defects efficiently.