Aim To investigate the regulatory mecha-nisms of donepezil on the expression and enzymatic ac-tivity of cytochrome P450 3A4(CYP3A4),elucidate the synergistic impact of hypoxia on CYP3A4 function,and reveal its potential association with drug-induced cardiotoxicity,particularly QT interval prolongation.Methods Western blot,co-immunoprecipitation,and gene knockdown techniques were employed to evaluate the effects of donepezil and hypoxia on CYP3A4 pro-tein expression.CYP3A4 enzymatic activity was as-sessed using an in vitro incubation system with rat liver microsomes combined with high-performance liquid chromatography(HPLC),and the half-maximal inhib-itory concentration(IC50)was determined.Results Donepezil(10 μmol·L-1)and hypoxia reduced CYP3A4 protein expression to 31.75％and 45.90％of the control levels,respectively.Both interventions activated the gp78-mediated ubiquitin-proteasome path-way,significantly increasing CYP3A4 ubiquitination levels by 2.1-fold compared to the control group,thereby promoting proteasomal degradation.Donepezil inhibited CYP3A4 enzyme activity with an IC50 of 83.4μmol·L-1,and hypoxia synergistically enhanced this inhibitory effect,reducing the IC50 to 20.79 μmol·L-1.Conclusion Donepezil downregulates CYP3A4 function through dual mechanisms involving ubiquitin-mediated proteasomal degradation and direct enzymatic inhibition.Hypoxia potentiates this effect,leading to impaired metabolism of CYP3A4 substrate drugs,ele-vated plasma drug concentrations(1.6-2.3-fold in-crease compared to normal metabolic conditions),and an increased risk of QT interval prolongation and other forms of cardiotoxicity.

Aim To investigate the regulatory mecha-nisms of donepezil on the expression and enzymatic ac-tivity of cytochrome P450 3A4(CYP3A4),elucidate the synergistic impact of hypoxia on CYP3A4 function,and reveal its potential association with drug-induced cardiotoxicity,particularly QT interval prolongation.Methods Western blot,co-immunoprecipitation,and gene knockdown techniques were employed to evaluate the effects of donepezil and hypoxia on CYP3A4 pro-tein expression.CYP3A4 enzymatic activity was as-sessed using an in vitro incubation system with rat liver microsomes combined with high-performance liquid chromatography(HPLC),and the half-maximal inhib-itory concentration(IC50)was determined.Results Donepezil(10 μmol·L-1)and hypoxia reduced CYP3A4 protein expression to 31.75％and 45.90％of the control levels,respectively.Both interventions activated the gp78-mediated ubiquitin-proteasome path-way,significantly increasing CYP3A4 ubiquitination levels by 2.1-fold compared to the control group,thereby promoting proteasomal degradation.Donepezil inhibited CYP3A4 enzyme activity with an IC50 of 83.4μmol·L-1,and hypoxia synergistically enhanced this inhibitory effect,reducing the IC50 to 20.79 μmol·L-1.Conclusion Donepezil downregulates CYP3A4 function through dual mechanisms involving ubiquitin-mediated proteasomal degradation and direct enzymatic inhibition.Hypoxia potentiates this effect,leading to impaired metabolism of CYP3A4 substrate drugs,ele-vated plasma drug concentrations(1.6-2.3-fold in-crease compared to normal metabolic conditions),and an increased risk of QT interval prolongation and other forms of cardiotoxicity.

MHNTs@PDA@ZIF-8 with rod-shaped core-shell structures was synthesized and used as sorbent in magnetic solid phase extraction(MSPE).MHNTs@PDA@ZIF-8-MSPE method coupled with gas chromatography-mass spectrometry(GC-MS)was employed to analyze sixteen kinds of polycyclic aromatic hydrocarbons(PAHs)in tea beverages.Vibrating sample magnetometer(VSM),Fourier transform infrared spectroscopy(FT-IR),X-ray diffraction(XRD),scanning electron microscopy(SEM)and nitrogen adsorption-desorption techniques were used to characterize the MHNTs@PDA@ZIF-8.The results demonstrated that the MHNTs@PDA@ZIF-8 exhibited significant magnetic properties and a large specific surface area.The experimental conditions that could affect MSPE were investigated,including adsorbent dosage,extraction time,desorption time,ionic strength,desorption solvent type,and desorption solvent volume.The optimal conditions were 10 mg of MHNTs@PDA@ZIF-8 as adsorbent,90 s under vortex extraction,and ultrasonic desorption for 60 s with 1 mL ofn-hexane.The sixteen kinds of PAHs showed good linearity in the concentration range of 5-500 μg/L(r2≥0.995).The limits of detection(S/N=3)and quantitation(S/N=10)were in the range of 0.1-0.8 μg/L and 0.3-2.6 μg/L,respectively.The recoveries of the method ranged from 60.9%to 114.7%,with relative standard deviations(n=3)ranging from 0.2%to 9.2%when the addition levels of sixteen kinds of PAHs were 10,50,and 100 μg/L.The method was simple,fast,sensitive and environmentally friendly,and suitable for detecting sixteen kinds of PAHs in tea beverages.

Objective To investigate the preliminary clinical effect of closed reduction and cannulated nail internal fixa-tion for femoral neck fracture assisted by robot navigation and positioning system.Methods From July 2019 to January 2020,16 cases of femoral neck fracture(navigation group)were treated with closed reduction and internal fixation guided by robot system,including 7 males and 9 females,aged 25 to 72 years old with an average of(53.61±5.45)years old;Garden classification of fracture:3 cases of type Ⅰ,3 cases of type Ⅱ,8 cases of type Ⅲ,2 cases of type Ⅳ.Non navigation group(control group):20 cases of femoral neck fracture were treated with closed reduction and hollow nail internal fixation,8 males and 12 females,aged 46 to 70 years old with an average of(55.23±4.64)years old;Garden type Ⅰ in 2 cases,type Ⅱ in 4 cases,type Ⅲ in 11 cases,type Ⅳ in 3 cases.The operation time,fluoroscopy times,guide needle drilling times,screw adjustment times,intraoperative bleeding volume and other indicators of two groups were evaluated.Results Both groups were followed up for 12 to 18 months with an average of(15.6±2.8)months.The fractures of both groups were healed without delayed union and nonunion.There was no significant difference in healing time between two groups(P=0.782).There was no significant differ-ence in Harris scores between two groups at the last follow-up(P=0.813).There was no significant difference in operation time between two groups(P＞0.05).There were significant differences between two groups in fluoroscopy times,guide needle drilling times,hollow screw replacement times,and intraoperative bleeding volume(P＜0.05).Conclusion Closed reduction and hollow screw internal fixation assisted by robot navigation system for femoral neck fracture has the advantages of minimally invasive operation,precise screw placement,and reduction of X-ray radiation damage during operation.

Objective:To investigate the effects of tibial second toe free flap bridged with blood flow and nerve in the treatment of severe flexion contracture of the proximal interphalangeal joint.Methods:A retrospective observational study was conducted. From March 2013 to October 2019, 9 patients with severe flexion contracture (type Ⅲ) of the proximal interphalangeal joint after trauma operation, conforming to the inclusion criteria, were hospitalized in Suzhou Ruihua Orthopaedic Hospital, including 5 males and 4 females, aged from 17 to 62 years. After the contracture tissue affecting the extension of the proximal interphalangeal joint was cut off, and the scar tissue was resected, the size of the volar wound near the proximal interphalangeal joint in extended position was 2.0 cm×1.0 cm-2.5 cm×1.5 cm, with the length of proper digital artery and nerve defect being 1.0-1.5 cm. A free flap of the same size as the wound was cut from the tibial side of the second toe and transplanted to repair the wound, and the defective proper digital artery and nerve was repaired by bridging with the tibial proper plantar digital artery and nerve of about 1.5 cm in length. The full-thickness skin graft was taken from the proximal tibial side of the lower leg to repair the wound at flap donor site. The wound at skin graft donor site was sutured directly. The survival of flap and skin graft was observed after operation. The patients were followed up, and at the last follow-up, the recovery of the affected finger and the second toe, including the donor and recipient areas were observed, the two-point discrimination distances of the flap repaired site and the pulp of the affected finger were observed and measured at the same time, the blood flow patency of bridged vessel of the affected finger was examined by Allen test, and the function of the proximal interphalangeal joint of the affected finger was evaluated according to Chinese Medical Association's standard for the range of motion of proximal interphalangeal joint.Results:The flaps and skin grafts survived smoothly after operation. The follow-up after operation lasted for 5 to 22 months, with a mean of 10 months. At the last follow-up, the flap repaired site had good shape, good color and texture, with the two-point discrimination distance being 9-12 mm, and the two-point discrimination distance of the pulp of the affected finger was 6-10 mm; the Allen test results of the affected fingers were all negative (i.e., the bridged vessels had good blood flow patency), with no recurrence of flexion contracture, and the function of the proximal interphalangeal joint was evaluated as excellent; the skin graft area of the second toe was not ruptured but was a little pigmented, and the flexion and extension activities of toe were good.Conclusions:The tibial second toe free flap bridged with blood flow and nerve has reliable therapeutic effect in the treatment of severe flexion contracture of the proximal interphalangeal joint, and the color and texture of the flap repaired area are good. Bridging to repair the severely contracted proper digital artery and nerve is beneficial to improve the blood supply of the finger body and rebuild the sensation.

Humans ; Lymphohistiocytosis, Hemophagocytic/complications* ; Neoplasms

Humans ; Child ; Primary Myelofibrosis/genetics* ; Prognosis ; Mutation

Objective:To compare the clinical effects of acute shortening-lengthening technique with antibiotic calcium sulfate-loaded bone transport technique for the treatment of segmental tibial defects after trauma.Methods:The clinical data of 58 patients with large tibial defects treated by Ilizarov technique in Xi′an Honghui Hospital Affiliated to Xi′an Jiaotong University from May 2014 to December 2019 were retrospectively analyzed. Thirty patients were treated by acute shortening-lengthening (group A), and they were divided into those who were successful in one-time shortening during operation (group A1) and those who needed gradual shortening after operation (group A2) according to different shortening conditions. And 28 patients by antibiotic calcium sulfate-loaded bone transport (group B). The external fixation time (EFT) and external fixation index (EFI) of the two groups were compared. Bone defect healing and limb functions were evaluated according to the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria. Complications were compared by Paley classification. The measurement data of normal distribution were expressed as ± s, and t-test was used for comparison between groups; the count data were expressed as n(%), and the chi-square test, Fisher exact probability method or Mann-Whitney U test were used for comparison between groups. Results:Patients were followed for(27.5±5.1)months. There was no significant difference in EFT, EFI, bone defect healing and limb functions between the two groups( P>0.05). The incidence of Grade-Ⅱ[41.2% (7/17)], Grade-Ⅲ [47.1% (8/17)] pin-tract infection in group A1 and Grade-Ⅱ[46.2% (6/13)], Grade-Ⅲ pin-tract [53.8% (7/13)] in group A2 was significantly higher than those in group B[14.3% (4/28)], [17.9% (5/28)] ( P<0.05). The number of complications per capita in group A1 [(1.4±0.3) times/case] and in group A2 [(1.5±0.3) times/case]was significantly higher than that in group B [(1.1±0.5) times/case]. Conclusions:Patients can be cured successfully by both acute shortening-lengthening and bone transport techniques. Compared with acute shortening-lengthening group, the complication incidence in antibiotic calcium sulfate-loaded bone transport group was lower, especially, the infection-related complications. Therefore, antibiotic calcium sulfate-loaded bone transport technique has a greater application prospect in patients with large segmental bone defects caused by infection or osteomyelitis.