OBJECTIVE: To investigate the biomechanical characteristics of Schatzker type Ⅱ tibial plateau fracture fixed by different bone grafting methods and internal fixations. METHODS: Twenty-four embalmed specimens of adult knee joint were selected to make Schatzker type Ⅱ tibial plateau fracture models, which were randomly divided into 8 groups (groups A1-D1 and groups A2-D2, n=3). After all the fracture models were restored, non-structural iliac crest bone grafts were implanted in group A1-D1, and structural iliac crest bone grafts in groups A2-D2. Following bone grafting, group A was fixed with a lateral golf locking plate, group B was fixed with lateral golf locking plate combined compression bolt, group C was fixed with lateral tibial "L"-shaped locking plate, and group D was fixed with lateral tibial "L"-shaped locking plate combined compression bolt. Compression and cyclic loading tests were performed on a biomechanical testing machine. A distal femur specimen or a 4-cm-diameter homemade bone cement ball were used as a pressure application mould for each group of models. The specimens were loaded with local compression at a rate of 10 N/s and the mechanical loads were recorded when the vertical displacement of the split bone block reached 2 mm. Then, compressive and cyclic loading tests were conducted on the fixed models of each group. The specimens were compression loaded to 100, 400, 700, and 1 000 N at a speed of 10 N/s to record the vertical displacement of the split bone block. The specimens were also subjected to cyclic loading at 5 Hz and 10 N/s within the ranges 100-300, 100-500, 100-700, and 100-1 000 N to record the vertical displacement of the split bone block at the end of the entire cyclic loading test. The specimens were subjected to cyclic loading tests and the vertical displacement of the split bone block was recorded at the end of the test. RESULTS: When the vertical displacement of the collapsed bone block reached 2 mm, the mechanical load of groups A2-D2 was significantly greater than that of groups A1-D1 ( P<0.05). The mechanical load of groups B and D was significantly greater than that of group A under the two bone grafting methods ( P<0.05); the local mechanical load of group D was significantly greater than that of groups B and C under the structural iliac crest bone grafts ( P<0.05). There was no significant difference ( P>0.05) in the vertical displacement of the split bone blocks between the two bone graft methods when the compressive load was 100, 400, 700 N and the cyclic load was 100-300, 100-500, 100-700 N in groups A-D. However, the vertical displacement of bone block in groups A1-D1 was significantly greater than that in groups A2-D2 ( P<0.05) when the compressive loading was 1 000 N and the cyclic load was 100-1 000 N. The vertical displacement of bone block in group B was significantly smaller than that in group A, and that in group D was significantly smaller than that in group C under the same way of bone graft ( P<0.05). CONCLUSION Compared with non-structural iliac crest bone grafts implantation, structural iliac crest bone grafts is more effective in preventing secondary collapse of Schatzker type Ⅱ tibial plateau fracture, and locking plate combined with compression bolt fixation can provide better articular surface support and resistance to axial compression, and the lateral tibial "L"-shaped locking plate can better highlight its advantages of "raft" fixation and show better mechanical stability.
Humans ; Bone Transplantation/methods* ; Tibial Fractures/physiopathology* ; Fracture Fixation, Internal/instrumentation* ; Biomechanical Phenomena ; Bone Plates ; Ilium/transplantation* ; Adult ; Tibia/surgery* ; Bone Cements ; Knee Joint/surgery* ; Male ; Tibial Plateau Fractures

OBJECTIVE To investigate the regulatory effects of couplet medicinals of Atractylodes macrocephala-Aucklandia lappa on gut microbiota and short-chain fatty acids （SCFAs） in the diarrhea-type irritable bowel syndrome （IBS-D） rats with spleen deficiency. METHODS The IBS-D rat model with spleen deficiency was induced by intragastric administration of Senna alexandrina combined with restraint stimulation. The model rats were divided into model group， positive control group （pinaverium bromide 1.5 mg/kg）， A. macrocephala-A. lappa low-dose， medium-dose and high-dose groups （0.7， 1.4， 2.8 g/kg）， with 6 rats in each group. Another 6 healthy rats were taken as the blank control group. The blank control group and the model group were given normal saline intragastrically， and other groups were given relevant drug liquid intragastrically， once a day， for consecutive 14 days. The general characteristics of rats and fecal water content were observed， and intestinal sensitivity [evaluating by abdominal wall withdrawal reflex （AWR） threshold] and the intestinal propulsion rate were determined. The serum levels of 5- hydroxytryptamine（5-HT）and SP were detected， and the pathological changes of colon tissue were observed； the protein expressions of 5-HT-3 receptor（5-HT3R）， 5-HT4R and 5-HT transporter（SERT） in colon tissue of rats were detected. 16S rRNA sequencing was performed for the feces of rats in blank control group， model group and A. macrocephala-A. lappa high-dose group； the contents of acetic acid， propionic acid and butyric acid in the feces of the rats were determined. RESULTS Compared with the model group， the body weight after 7 and 14 days of medication， fecal water content， AWR threshold， and the protein expressions of 5-HT4R and SERT in colon tissue were increased significantly in the A. macrocephala-A. lappa medium-dose and high-dose groups （P＜0.05 or P＜0.01）； serum contents of 5-HT and SP， intestinal propulsion rate （except for A. macrocephala-A. lappa medium-dose group）， the protein expression of 5-HT3R in colon tissue were decreased significantly （P＜0.01）； diarrhea relief， mental state recovery， and partially recovery of the structure of colon tissue were all found； moreover， the diversity and species number of gut microbiota were reduced in A. macrocephala-A. lappa high-dose group and the content of butyric acid in fecal samples was significantly reduced （P＜0.05）. CONCLUSIONS The compatibility of A. macrocephala and A. lappa can improve intestinal motility and sensitivity of IBS-D model rats with spleen deficiency， and alleviate diarrhea. This may be related to improving changes in intestinal microbiota structure， reducing 5-HT expression and butyric acid content， and increasing 5-HT4R and SERT expression.

Objective:To characterize the biomechanics of distal dynamic locking and distal static locking of proximal femur bionic nails (PFBN) in fixation of intertrochanteric fractures by a finite element analysis.Methods:The CT image data from the hip to the upper tibia from an adult male volunteer were used to establish a three-dimensional model of the femur by Mimics 20.0 and Geomagic 2013 which was processed further into a model of Evans type I intertrochanteric fracture by software NX 12.0. With reference to the internal fixation parameters commonly used, 4 models of PFBN fixation were established: distal single transverse nail dynamic locking (model A), single oblique nail dynamic locking (model B), single nail static locking (model C) and double nail dynamic locking (model D). Abaqus 6.14 software was used to load and analyze the internal fixation stresses and displacements of fracture ends.Results:Under a 2100N loading, the peak stress was located upon the main nail in the 4 models. The smallest peak stress upon the main nail was in Model D (161.9 MPa), decreased by 15.9% compared with model A (192.5 MPa), by 15.6% compared with model B (191.9 MPa), and by 0.9% compared with model C (163.3 MPa). The peak stress upon the fixation screw was the largest in model A (95.3 MPa), the smallest in model B (91.5 MPa), and 91.5 MPa and 92.2 MPa in models C and D, respectively. The overall displacements of the implants, in a descending order, were 10.14 mm in model A, 10.10 mm in model B, 10.09 mm in model C, and 10.05 mm in model D. Similarly, the displacements of fracture ends were 0.125 mm in model A, 0.121 mm in model B, 0.110 mm in model C, and 0.098 mm in model D.Conclusion:Compared with dynamic locking, distal static locking of PFBN provides a better mechanical stability and reduces stress concentration upon internal fixation.

Objective To study the mechanism of the treatment of metabolism associated steatohepatitis(MASH)in rats with Xiaoyao Wan.Methods Twenty-four SD male rats were randomly divided into control group(CON group,n=8)and model group(n=8).The model group was given high-fat diet,carbon tetrachloride(CCl4)subcutaneous injection,hunger and satiety disorder and tail clamping for four weeks to establish the MASH model,and the rats were randomly divided into the MOD group and the Xiaoyao Wan group(XYW group),with 8 rats in each group.The rats of the XYW group were given Xiaoyao Wan,the other two groups were given normal saline.Four weeks after administration,the serum biochemical indexes and oxidative stress indexes of rats in different groups were detected.The pathological sections of rat liver tissue were observed by hematoxylin-eosin(HE)stai-ning and oil red O staining.The expression of cytochrome P450 2E1(CYP2E1),factor-related apoptosis ligand(FasL),tumor necrosis factor-α(TNF-α)and tumor growth factor-β1(TGF-β1)in rat liver were detected by Western blot method.The relative contents of CYP2E1,FasL,TNF-α and TGF-β1 mRNA in liver tissue were de-tected by RT-qPCR.Results The general condition of rats in the XYW group was significantly improved compared with the MOD group;the level of hepatic index was significant decrease compared with the MOD group(P＜0.01)and the level of body mass index was significant increase compared with the MOD group(P＜0.01);the serum levels of triglyceride,total cholesterol,low-density lipoprotein cholesterol,aspartate aminotransferase,alanine aminotransferase,malondialdehyde,monocyte chemotactic protein-1,TNF-α,and interleukin(IL)-18 were signif-icantly reduced compared with the MOD group(all P＜0.05),and the levels of high-density lipoprotein choles-terol,superoxide dismutase,and IL-10 were significantly elevated compared with the MOD group(all P＜0.05);the content of lipid droplets in hepatocytes of rats was significantly reduced compared with the MOD group under light microscope;the protein levels of CYP2E1,FasL,TNF-α and TGF-β1 in liver tissues were significantly re-duced compared with the MOD group(all P＜0.05),and the relative contents of CYP2E1,FasL,TNF-α and TGF-β1 mRNA were significantly reduced compared with the MOD group(all P＜0.05).Conclusion Xiaoyao Wan can regulate the expression of CYP2E1,FasL,TNF-α and TGF-β1 in the liver tissue of MASH rats by reduc-ing the accumulation of fat in the liver,so as to achieve the purpose of treating MASH.

Objective:To summarize the genotype and clinical characteristics of chylomicron retention disease (CMRD) caused by secretion associated Ras related GTPase 1B (SAR1B) gene variations.Methods:Clinical data and genetic testing results of 2 children with CMRD treated at Children′s Hospital of Fudan University and Jiangxi Provincial Children′s Hospital from May 2022 to July 2023 were summarized. To provide an overview of the clinical and genetic characteristics of CMRD caused by SAR1B gene variations, all of the literature was searched and reviewed from China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, China VIP database, China Biology Medicine disc and PubMed database (up to January 2024) with "chylomicron retention disease" "Anderson disease" or "Anderson syndrome" as the search terms. All relevant literatures were reviewed to summarize the clinical and genetic features of CMRD caused by SAR1B gene variations.Results:One 11-year-old boy and one 4-month-old girl with CMRD. Both patients had lipid malabsorption, failure to thrive, decreased cholesterol, elevated transaminase and creatine kinase, and Vitamin E deficiency, with homozygous variations (c.224A>G) and compound heterozygous variations (c.224A>G and c.554G>T) in SAR1B gene, respectively. Case 1 was followed up for over a month, and he still occasionally experienced lower limb muscle pain. Case 2 was followed up for more than a year, and her had caught up to normal levels. Both patients had no other significant discomfort. Literature search retrieved 0 Chinese literature and 22 English literatures. In addition to the 2 cases reported in this study, a total of 51 patients were identified as CMRD caused by SAR1B gene variations. Twenty-one types of SAR1B variants 10 missense, 4 nonsense, 3 frameshift, 1 in-frame deletion, 1 splice, 1 gross deletion, and 1 gross insertion-deletion were found among the 51 CMRD cases. Among all the patients, 49 cases had lipid malabsorption (43 cases had diarrhea or fatty diarrhea, 17 cases had vomiting, and 12 cases had abdominal distension), 45 cases had lipid soluble Vitamin deficiency (43 cases had Vitamin E deficiency, 10 cases had Vitamin A deficiency, 9 case had Vitamin D deficiency, and 5 cases had Vitamin K deficiency), 35 cases had failure to thrive, 32 cases had liver involvement (32 cases had elevated transaminases, 5 cases had fatty liver, and 3 cases had hepatomegaly), 29 cases had white small intestinal mucosa under endoscopy, and 17 cases had elevated creatine kinase, 14 cases had neuropathy, 5 cases had ocular lesions, 2 cases had acanthocytosis, 1 case had decreased cardiac ejection fraction, and 1 case was symptom-free.Conclusions:Early infancy failure to thrive and lipid malabsorption are common issues for CMRD patients. The laboratory tests are characterized by hypocholesterolemia with or without fat-soluble Vitamin deficiency, elevated liver enzymes and (or) creatine kinase. Currently, missense variations are frequent among the primarily homozygous SAR1B genotypes that have been described.

Objective To establish and evaluate a rapid detection method for SARS-CoV-2 based on reverse transcriptase-recombinase aided amplification(RT-RAA)combined with the clustered regularly interspaced short palindromic repeats(CRISPR)/Cas12a system.Methods RT-RAA primers and CRISPR-derived RNA(crRNA)were designed based on the nucleocapsid(N)gene of SARS-CoV-2 from NCBI database.The detection system was optimized with magnesium acetate(MgAc)concentration,RT-RAA reaction tempera-ture and time and LbCas12a reaction temperature.The sensitivity and specificity of the method were evaluated using recombinant plas-mids(100-106 copies/μL)and other respiratory pathogens.The RT-RAA-CRISPR/Cas12a method was compared with RT-PCR by tes-ting 70 clinical samples in parallel.Results The optimized RT-RAA-CRISPR/Cas12a assay could detect SARS-CoV-2 within 50 min at 37 ℃.The limit of detection was 10 copies/μL for the fluorescence-based method and 1×102 copies/μL for the lateral flow assay.The method specifically detected SARS-CoV-2 without cross-reactivity to other respiratory pathogens.The results of testing 70 clinical samples using RT-RAA-CRISPR/Cas12a showed agreement of 100％with those of RT-PCR.Conclusion The established RT-RAA-CRISPR/Cas12a assay for SARS-CoV-2 detection is rapid,cost-effective,highly sensitive and specific.It can be performed by less experienced personnel and no expensive equipment is required,thus it may provide a new approach for rapid clinical diagnosis and large-scale on-site screening of SARS-CoV-2.

ObjectiveTo investigate the effect and mechanism of Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex in regulating the intestinal function in the rat model of slow transit constipation （STC） due to yang deficiency via the vasoactive intestinal peptide （VIP）/cathelicidin antimicrobial peptide （cAMP）/protein kinase A （PKA）/aquaporin （AQP） pathway. MethodSD rats were randomized into 6 groups （n=6）， including a control group， a model group， high-， medium-， and low-dose Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex groups， and a prucalopride group. Other groups except the control group were treated with loperamide hydrochloride combined with ice water by gavage for the modeling of STC due to yang deficiency. The number of fecal pellets， time to the first black stool defecation， fecal water content， intestinal propulsion rate， and score of fecal properties were recorded in each group. At the end of the treatment， the colon was stained with hematoxylin-eosin （HE） to reveal the histopathological changes and Alcian blue/periodic acid-Schiff （AB-PAS） to reveal the secretion of colonic mucus. The enzyme-linked immunosorbent assay （ELISA） was employed to measure the level of VIP in the serum. The mRNA level of AQP in the colon was measured by polymerase chain reaction （Real-time PCR）. Immunohistochemical staining was performed to observe the expression of AQPs in the colon and kidney tissues. Western blot was performed to determine the protein levels of cAMP， PKA， and VIP in the colon tissue. ResultCompared with the control group, the model group had longer time to the first black stool defecation, reduced fecal pellets and water content, reduced Bristol Stool Form Scale score and intestinal propulsion rate, and constipation aggravated（P<0.01）. Moreover, increased the intestinal lesions, reduced the mucus secretion, reduce the serum VIP level, up-regulated the expression levels of AQP1 in the colon and kidney tissues, inhibited the expression of AQP3 and AQP9（P<0.01）., and down-regulated the protein levels of cAMP, PKA, and VIP in the colon tissue. Compared with the model group， the high-dose Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex group had shortened time to the first black stool defecation， increased fecal pellets and water content， increased Bristol Stool Form Scale score and intestinal propulsion rate， and alleviated constipation symptoms. Moreover， high-dose Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex reduced the intestinal lesions， increased the mucus secretion， elevated the serum VIP level（P<0.01）.， down-regulated the expression levels of AQP1 in the colon and kidney tissues， promoted the expression of AQP3 and AQP9（P<0.05，P<0.01）， and up-regulated the protein levels of cAMP， PKA， and VIP in the colon tissue. The medium- and low-dose groups had weaker effect than the high-dose group（P<0.01）. ConclusionHigh-dose Aconiti Lateralis Radix Praeparata-Cinnamomi Cortex can improve the intestinal motility and balance the intestinal water and fluid metabolism by up-regulating the VIP/cAMP/PKA/AQP pathway， thereby mitigating the constipation symptoms in the rat model of slow transit constipation due to yang deficiency.

Pain is a defensive response to body injury or potential injury, and is also the most common clinical manifestations in orthopedic trauma. Pain is critical to determine the causes of injury and therapeutic plans in the diagnosis and treatment of orthopedic trauma. Post-traumatic acute and chronic pain not only brings physical pain to patients, but also induces a variety of complications. Moreover, improper evaluation and management of pain can easily lead to missed diagnosis and misdiagnosis, thus prolonging the treatment cycle and affecting the quality of life. At present, the management of pain has no normative standard in the diagnosis and management of orthopedic trauma. Academician Zhang Yingze′s team has summarized the pain characteristics of various orthopedic trauma patients, traced back to the sources, and conduced the innovative concept of "pain" to get the melon to address issues such as insufficient pain assessment, incomplete etiology analysis and inadequate diagnostic thinking, hoping to achieve rapid and accurate diagnosis and early treatment. The authors elaborate on the connotation of the innovative concept of "pain" to get the melon and its application in clinical orthopedic trauma, aiming to explore the application value of this innovative concept, achieve rapid and accurate diagnosis of orthopedic trauma and provide a reference for formulating reasonable diagnosis and treatment programs.

Objective:To explore the application and clinical efficacy of an innervated arterialised venous flap of the first dorsal metacarpal in reconstruction of thumb and finger pulp defects.Methods:From December 2021 to August 2022, 17 patients received surgery for reconstruction of thumb and finger pulp defects in the Department of Hand Surgery of Sichuan Modern Hospital. All were carried out in emergency surgery. The affected digits included: 3 thumbs, 4 index fingers, 6 middle fingers, 1 ring finger and 3 little fingers. After emergency debridement, a flap of the first dorsal metacarpal carrying superficial radial nerve and arterialised vein was taken for reconstruction of the defect. Donor site of the flap was directly closed with sutures. The survival and functional recovery of the digits and flaps were evaluated through postoperative follow-ups via outpatient visit and telephone and WeChat interviews.Results:Seven flaps developed blisters after surgery, which gradually subsided and healed after dressing change. The rest of 10 flaps survived smoothly, without any vascular compromise. All of the 17 patients(17 digits) had postoperative follow-up for 3-15 months, with 8 months in average. Appearance of thumb and finger pulps were good, with sensation restored to S 1-S 3+, according to the sensory function evaluation criteria of the British Medical Research Council(BMRC). According to Evaluation Trial Standards of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association, all 17 patientswere in excellent of total active movement(TAM). Conclusion:Innervated arterialised venous flap of the first dorsal metacarpal is reliable in reconstruction of the defects of digit pulps with good function and appearance. The flap is easy to take and with a satisfactory recovery of sensation.

Objective:To analyze the application value of sakubatril valsartan in the treatment of chronic heart failure (CHF) based on cardiopulmonary test system.Methods:One hundred and thirty-five CHF patients admitted to the Affiliated Hospital of Jining Medical Collegefrom January 2019 to August 2020 were divided into the observation group (67 cases) and the control group (68cases) by random number table method. Both groups were treated with bisoprolol. The observation group was treated with the combination of sakubatril valsartan, and the control group was treated with the combination of benapril. The efficacy and cardiac function indicators of the two groups were compared. The cardiopulmonary exercise test system was used to measure the patient′s maximum exercise time (Tmax), maximum exercise Watt (Wmax), peak volume oxygen (Peak VO 2) and volume of anaerobic threshold oxygen (VO 2AT), and the incidence of adverse reactions were calculated. Results:The total effective rate in the observation group was higher than that in the control group: 92.54% (62/67) vs. 77.94%(53/68), the difference was statistically significant ( χ2 = 5.70, P<0.05). After the treatment, the levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) and soluble ST2 (sST2) in the observation group were lower than those in the control group: (2 000.47 ± 517.85) ng/L vs. (2 777.39 ± 812.49) ng/L, (0.33 ± 0.10) μg/L vs. (0.37 ± 0.09) μg/L, and the left ventricular ejection fraction (LVEF) was higher than that in the control group: (8.12 ± 6.44)% vs. (41.93 ± 6.73)%, the differences were statistically significant ( P<0.05). After the treatment, the left ventricular end-diastolic diameter (LVEDd), left ventricular end-systolic diameter (LVEDs), left ventricular mass index (LVMI), left atrial volume index (LAVI) in the observation group were lower than those in the control group: (55.47 ± 6.93) mm vs. (62.00 ± 7.18) mm, (37.14 ± 6.36) mm vs. (41.35 ± 6.43) mm, (136.76 ± 7.13) mg/m 2 vs. (140.98 ± 7.47) mg/m 2, (28.23 ± 2.59) ml/m 2 vs. (31.98 ± 2.17) ml/m 2; the Tmax, Wmax, PeakVO 2 and VO 2AT in the observation group were higher than those in the control group: (619.08 ± 65.36) s vs. (58.70 ± 52.44) s, (142.96 ± 16.05) W vs. (124.19 ± 13.38) W, (20.00 ± 5.74) ml/(min·kg) vs. (18.13 ± 3.58) ml/(min·kg), (13.89 ± 3.69) ml/(min·kg) vs. (11.23 ± 2.36) ml/(min·kg), the differences were statistically significant ( P<0.05). However, there was no statistically significant in the incidence of adverse reactions between the two groups ( P>0.05). Conclusions:Sakubatril valsartan in the treatment of CHF can not only optimize the efficacy and improve cardiac function, but also benefit cardiac exercise rehabilitation of patients, and not increase the safety risk.