Objective To observe any effect of low intensity pulsed ultrasound (LIPUS) on the expression of integrin-focal adhesion kinase (FAK)-mitogen-activated protein kinase (MAPK) mechanochemical transduction pathway-related proteins in the chondrocytes of rabbits with knee osteoarthritis (OA).Methods Of the 18 New Zealand white rabbits selected for the study,twelve received knee anterior cruciate ligament transection to model OA.The remaining 6 rabbits served as normal controls.At the 4th week after modeling the rabbits were sacrificed and chondrocytes were isolated and cultured in vitro.All the cultured cells were randomly divided into three groups:a normal control group (NC),an OA model group (OA) and an OA model plus LIPUS group (OA + LIPUS).When the cells had been cultured to the 2nd passage,the NC group and OA group cells had received no treatment.The OA + LIPUS group cells were exposed to 40 mW/cm2 of LIPUS for 20 min,once a day for 6 days.The expression of collagen protein type Ⅱ,aggrecan,MMP-13,integrin β1 p-FAK and p-p38,p-ERK1/2 and p-JNK Mapks were detected by Western blotting.Results Compared with the NC group,the expression of collagen type Ⅱ and aggrecan was significantly lower in the OA and OA + LIPUS groups,with more significantly lower expression of collagen type Ⅱ and aggrecan in the OA group than in the OA + LIPUS group.Compared with the NC group,the expression of MMP-13 was significantly higher in the OA and OA + LIPUS groups,with a significantly larger increase in the OA group.Compared with the NC group,the expression of integrin β1 and p-FAK was also significantly higher in the OA and OA + LIPUS groups,with a significantly larger increase in the OA + LIPUS group.Compared with the NC group,the expression of p-p38,p-ERK1/2 and p-JNK was also significantly higher in the OA group,but compared with the OA group,the expression of those kinases was,on average,significantly lower in the OA + LIPUS group.Conclusions LIPUS can inhibit the degradation of collagen type Ⅱ and aggrecan,and inhibit the expression of MMP-13,p-p38,p-ERK1/2 and p-JNK in OA chondrocytes,at least in vitro.At the same time,LIPUS can increase the expression of integrin β1 and p-FAK.The results show that LIPUS may activate an integrin-FAK-MAPK mechanochemical transduction pathway to induce changes in the extracellular matrix of chondrocytes.

OBJECTIVETo develop the knowledge, attitude and practice questionnaire on the prevention and control of occupational diseases for occupational groups, and to provide a convenient and effective tool for the survey of knowledge, attitude, and behavior on the prevention and control of occupational diseases in occupational groups and the evaluation of intervention effect.

METHODSThe initial questionnaire which was evaluated by the experts was used to carry out a pre-survey in Guangzhou, China. The survey results were statistically analyzed by t test, identification index method, correlation analysis, and Cronbach's a coefficient method. And then the questionnaire was further modified, and the content of the questionnaire was determined finally.

RESULTSAfter modification, there were 18 items on knowledge, 16 items on attitude, and 12 items on behavior in the "Knowledge, attitude and practice questionnaire on the prevention and control of occupational diseases for enterprise managers"; there were 19 items on knowledge, 10 items on attitude, and 11 items on behavior in the "Knowledge, attitude and practice questionnaire on the prevention and control of occupational diseases for workers".

CONCLUSIONThe knowledge, attitude and practice questionnaire on the prevention and control of occupational diseases for occupational groups is developed successfully, and it is a convenient and effective tool for the survey of knowledge, attitude, and behavior on the prevention and control of occupational diseases in occupational groups and the evaluation of intervention effect.

OBJECTIVEStudy the current quality management situation of enterprises marketing corneal contact lens via systemic investigations and explore effective administration countermeasures in the future.

METHODSThe quality management indicators of sixty-two corneal contact lens marketing enterprises in Xuhui district of Shanghai were systematically investigated and enterprises of different operation models was compared and analyzed.

RESULTSWholesale enterprises and retail chain enterprises are apparently better than independent enterprises almost in all facets.

CONCLUSIONFacilitate market accession of corneal contact lens marketing enterprises, encourage the business model of retail chain, enhance supervision of corneal contact lens marketing enterprises, especially independent franchisors.

Aiming at the characteristics of biochemistry and the special advantage of flash and basing on teaching practice,we set up a set of biochemistry flash animation database,providing a series of immediate flashes and being applied to teaching practice of biochemistry,which shows the great potential of flash in improving biochemistry teaching quality.

Objective To observe the therapeutic effect and mechanism of the aqueous extract of ephedra sinica on brain damage after subarachnoid hemorrhage(SAH)in rats.Methods Totally 50 rats of Sprague-Dawley were randomly divided into control group,model group and three groups treated with different concentrations(4,12,36 mg/kg).The changes of the cerebral water content,malondialdehyde(MDA),glutathione peroxidase(GSH-Px)and hydroxy radical of brain tissue were recorded,and he-matoxylin-eosin(HE)staining was used to test the subarachnoid haemorrhagia and oedema,and immunohistochemistry and western blot were carried out to assay the expression of complement C3 in brains of different animal in different group 3d after operation. Results On the postoperative 3 days,compared with the model group,the content of MDA、GSH-Px activity and hydroxyl radical of 12、36 mg/kg treatment groups significantly reduced(P <0.01 ),the content of MDA of 4 mg/kg treatment group not change (P >0.05),but GSH-Px activity and inhibition of hydroxyl radical significantly reduced(P <0.01),and the cerebral water content of 12,36 mg/kg groups were obviously lower compared with model group.The expression of complement C3 was significantly lower on 36 mg/kg treatment group and edema reduced.Conclusion The aqueous extract of ephedra could significantly inhibit the activity of complement C3,prevent the production of MDA、GSH-Px and hydroxyl radical,reduce the severity of cerebral edema and the in-flammatory response,which has a better therapeutic effect SAH animals.

Objective Study the current quality management situation of enterprises marketing corneal contact lens via systemic investigations and explore effective administration countermeasures in the future. Methods The quality management indicators of sixty-two corneal contact lens marketing enterprises in Xuhui district of Shanghai were systematical y investigated and enterprises of different operation models was compared and analyzed. Results Wholesale enterprises and retail chain enterprises are apparently better than independent enterprises almost in al facets. Conclusion Facilitate market accession of corneal contact lens marketing enterprises, encourage the business model of retail chain, enhance supervision of corneal contact lens marketing enterprises, especially independent franchisors.

Objective:To investigate the relationship between tube voltage kV value for head and neck CT angiography and body weight.Methods:A total of 120 patients with suspected vascular disease of the head and neck who underwent CT angiography of the head and neck in Beihai People's Hospital from January 2020 to May 2022 were included in this study. Patients were divided into three groups according to different tube voltages: group A (tube voltage 120 kV, n = 45), group B (tube voltage 100 kV, n = 45) and group C (tube voltage 80 kV, n = 30). Patients in group A were divided into group A1 (< 70 kg, n = 15), group A2 (70-85 kg, n = 15) and group A3 (> 85 kg, n = 15) according to different body weights. Patients in group B were divided into group B1 (< 70 kg, n = 15), group B2 (70-85 kg, n = 15) and group B3 (> 85 kg, n = 15) according to different body weights. Patients in group C were divided into group C1 (< 70 kg, n = 15) and group C2 (70-85 kg, n = 15) according to different body weights. Group C3 was not used. The contrast medium used was Loversol. The CT value, image noise, signal-to-noise ratio, contrast to noise ratio, and effective radiation dose of arterial vessels in each group were measured. The images were subjectively evaluated by two physicians who had senior professional titles using a 5-point rating scale. Results:Subjective score of image quality was all ≥ 3 grade in each group. There was no significant difference in image quality rating between groups A1 and A2 and groups B1, B2, and C1. There was a remarkable difference in image quality rating between groups A3, B3, and C2 and the other groups. There was a significant difference in the CT value of blood vessels at four different levels between groups A1, B1 and C1 ( F = 76.82, 64.62, 98.79, 71.85, all P < 0.001). There was a significant difference in CT value of blood vessels at four different levels between groups A2, B2 and C2 ( F = 159.82, 112.33, 108.22, 135.18, all P < 0.001). There was a significant difference in CT value of blood vessels at four different levels between groups A3 and B3 ( t = 4.40, 4.27, 3.91, 3.59, all P < 0.05). In groups B3 and C2, the image noise was remarkably increased, signal to noise ratio and contrast to noise ratio were remarkably decreased compared with those in the other groups. The effective radiation dose of arterial vessels in group B1 was 47% lower than that in group A1 and the effective radiation dose of arterial vessels in group C1 was 73% lower than that in group A1 ( F = 116.18, P < 0.001). The effective radiation dose of arterial vessels in group B2 was 49% lower than that in group A2, and the effective radiation dose of arterial vessels in group C2 was 66% lower than that in group A2 ( H = 35.40, P < 0.001). The effective radiation dose in group B3 was 35% lower than that in group A3 ( t = 3.59, P < 0.05). Conclusion:In CT angiography of the head and neck, the selection of tube voltage kV value is related to body weight. Tube voltage 80 kV is suitable for patients with a body weight < 70 kg, tube voltage 100 kV for patients with a body weight of 70-85 kg, and tube voltage 120 kV for patients with a body weight > 85 kg. These tube voltages can decrease effective radiation dose and ensure image quality, meeting the requirement for clinical diagnosis.

BACKGROUND:The maximum muscle strength is typically used for evaluating the recovery of muscle function after anterior cruciate ligament reconstruction.Recent studies have suggested that neuromuscular function should also be considered,such as rate of force development,which measures the slope of the force time curve at different time intervals under conditions of isometric muscle contraction. OBJECTIVE:To elaborate on the current research status and shortcomings of muscle isometric rate of force development in patients undergoing anterior cruciate ligament reconstruction surgery,and analyze the degree of defects in quadriceps femoris and hamstring isometric rate of force development at different times after surgery;to analyze the effect of isometric rate of force development on postoperative functional performance,thereby providing important information for optimizing postoperative rehabilitation following anterior cruciate ligament reconstruction,reducing secondary injury to patients,and reducing the incidence of knee osteoarthritis. METHODS:Literature retrieval of CNKI,VIP,WanFang and PubMed was performed using"anterior cruciate ligament,rate of force development"as Chinese search terms and"anterior cruciate ligament,rate of force development,rate of torque development"as English search terms.Finally,69 articles were included according to inclusion and exclusion criteria. RESULTS AND CONCLUSION:Most studies have found defects in bilateral muscle isometric rate of force development in patients undergoing anterior cruciate ligament reconstruction within 6 months.Early isometric rate of force development of the bilateral hamstring muscles(i.e.the slope of the force time curve at any time interval during muscle contraction of 100 ms)showed significant improvement after 6 months.However,long-term defects in early isometric rate of force development of the bilateral quadriceps indicate long-term damage to the neuromuscular function of the quadriceps after surgery.There is limited research on late isometric rate of force development(the slope of the force time curve at any time interval after 100 ms of muscle contraction),and conclusions cannot be drawn.Regarding landing exercises(jumping to the ground,lateral cutting,etc.)and daily activities(walking,running),early isometric rate of force development of the quadriceps is more correlated with isometric peak torque.Abnormal biomechanical changes during exercise are considered an important risk factor for secondary injury and traumatic knee osteoarthritis in patients.Actively improving early isometric rate of force development of the quadriceps may reduce the incidence of secondary injury and traumatic knee osteoarthritis.Currently,there is limited evidence to suggest that whole-body vibration training can improve early isometric rate of force development of the quadriceps femoris in patients undergoing anterior cruciate ligament reconstruction.It is recommended to use neuromuscular electrical stimulation to intervene in the quadriceps and hamstring in the early postoperative stage and implement explosive force and high resistance training in the late postoperative stage,which may improve the isometric rate of force development in patients.Generating sufficient muscle strength in a short period of time is necessary to effectively protect the anterior cruciate ligament,while the relationship between isometric rate of force development in the hamstring muscle and functional performance is still unclear,which may provide information on preventing secondary injury in patients.It is recommended to use the isometric rate of force development as one of the evaluation indicators for guiding rehabilitation and restoring movement.In addition to focusing on improving symmetry and differences from normal individuals,the hamstring to quadriceps strength ratio should also be considered.An appropriate range of ratios can ensure the balance of muscles during rapid muscle exertion,which may reduce the occurrence of secondary injuries.However,the normal range of ratios is not yet clear.Future research should consider the effects of graft type and knee flexion angle on isometric rate of force development,in order to identify neuromuscular dysfunction in patients as much as possible and help them recover better.

Objective:To analyze the costs and effectiveness of five common screening modes and genetic screening for thalassemia in China in order to find the optimal way and provide evidence for the implementation of thalassemia prevention and control projects in Hunan Province.Methods:From June 2020 to April 2021, 12 971 couples from 14 cities and autonomous prefectures in Hunan Province were selected as the study population. The diagnosis of thalassemia was based on the results of genetic testing. Results of routine blood test and hemoglobin electrophoresis were collected and analyzed. The efficacy of five screening modes, at the cut-off value of <80 fl or 82 fl for the mean corpuscular volume (MCV), was analyzed by positive predictive value, negative predictive value, Jorden index and cost-effectiveness ratio. Sensitivity analysis was used to assess the feasibility of genetic screening at different costs after fixing the costs of routine blood and hemoglobin electrophoresis. The five thalassemia screening models are as follows: Mode 1: The woman had a blood routine test first. If the result was positive, the spouse required a blood routine test. If both results were positive, a thalassemia gene test should be offered to the couple. Mode 2: Both husband and wife were screened by blood routine and hemoglobin electrophoresis. If one or both of them were positive, both would be tested for thalassemia gene. Mode 3: The couple received blood routine tests initially. If either was positive, both should receive hemoglobin electrophoresis testing. If either was positive, both parties will conduct thalassemia gene testing. Mode 4: The woman was screened by blood routine and hemoglobin electrophoresis. If any one of them was positive, the woman would be tested for thalassemia gene. If the gene test result was positive, the spouse should receive thalassemia gene. Mode 5: Both spouses conducted a blood routine test. If either was positive, both would conduct hemoglobin electrophoresis test. If both were positive, both spouses should receive thalassemia gene testing. Gene testing mode: The woman would be tested for thalassemia, and her spouse would have thalassemia test too if her result was positive.Results:When using MCV<80 fl as the cut-off for diagnosing thalassemia, the Youden indices of the five prenatal screening modes in Hunan Province were 0.551, 0.639, 0.898, 0.555 and 0.356, while when using MCV<82 fl as the cut-off, the Youden indices were 0.549, 0.629, 0.851, 0.548 and 0.356. When the MCV cut-off value was <80 fl, the missed diagnosis rates of the five screening modes were 44.44%, 0.00, 0.00, 18.52% and 62.96%, and the cost-effectiveness ratios were 21 709, 250 939, 76 870, 138 463 and 92 860 yuan (RMB)/couple, respectively. When the price of genetic testing was lower than 55 yuan (RMB), the cost-effectiveness ratio of genetic screening was lower than that of Mode 3.Conclusions:MCV<80 fl can be considered as the positive criteria in blood routine screening for thalassemia in Hunan Province, and the cost-effectiveness ratio of Mode 3 (the couple received blood routine tests initially. If either was positive, both should receive hemoglobin electrophoresis testing. If either was positive, both parties will conduct thalassemia gene testing) is the best. Genetic screening has certain advantages with the decreasing price.