Polymyxin serves as the"last line of defense"for treating infection with multidrug-resistant Gram-ne-gative bacteria.However,the emergence and spread of polymyxin-resistant genes such as mcr-1 severely weakens its clinical efficacy.This paper systematically summarizes the antimicrobial and resistance mechanisms of polymy-xin,comprehensively summarizes the current research progresses in polymyxin sensitizers particular focusing on three aspects:natural compounds,synthetic small molecules,and drug repurposing.Furthermore,this paper explores the innovative strategies of gene intervention,new targets,and nanotechnology-based formulations in the develop-ment of sensitizer,aiming to provide systematic theoretical support and research ideas against polymyxin resistance.

Polymyxin serves as the"last line of defense"for treating infection with multidrug-resistant Gram-ne-gative bacteria.However,the emergence and spread of polymyxin-resistant genes such as mcr-1 severely weakens its clinical efficacy.This paper systematically summarizes the antimicrobial and resistance mechanisms of polymy-xin,comprehensively summarizes the current research progresses in polymyxin sensitizers particular focusing on three aspects:natural compounds,synthetic small molecules,and drug repurposing.Furthermore,this paper explores the innovative strategies of gene intervention,new targets,and nanotechnology-based formulations in the develop-ment of sensitizer,aiming to provide systematic theoretical support and research ideas against polymyxin resistance.

Objective:To establish a high performance liquid chromatography method for the simultaneous determination of dimethyl oxalate (DMO) and diethyl oxalate (DEO) in workplace air.Methods:From January 2022 to January 2023, air samples were collected by silica gel tubes, desorbed by acetonitrile, separated by C18 chromatographic column, detected by photo-array detector, and retention time was used to characterize and peak area was used to quantify at 210 nm wavelength.Results:The linear relationships of DMO and DEO were good, r>0.999. The detection limits of DMO and DEO were 0.39 and 0.52 μg/ml, respectively. The quantitative limit was 1.28 μg/ml for DMO and 1.72 μg/ml for DEO. Average desorption efficiency for DMO was 82.40%-92.72%, and DEO was 94.13%-97.69%. The intra-assay precision of DMO was 1.87%-6.18%, and DEO was 2.25%-3.31%. Inter-assay precision of DMO was 3.29%-5.73%, and DEO was 1.38%-2.94%. Average sampling efficiencies were 100% for both DMO and DEO. Breakthrough capacity of DMO was 37.61 mg (200 mg solid adsorbent), DEO was >28.11 mg (200 mg solid adsorbent). Samples should be stored at 4 ℃ for at least 7 days. Conclusion:This method is easy to operate and has strong practicability. All indicators meet the requirements of the specification, and it is suitable for the simultaneous determination of DMO and DEO in the workplace air.

Objective:To establish a high performance liquid chromatography method for the simultaneous determination of dimethyl oxalate (DMO) and diethyl oxalate (DEO) in workplace air.Methods:From January 2022 to January 2023, air samples were collected by silica gel tubes, desorbed by acetonitrile, separated by C18 chromatographic column, detected by photo-array detector, and retention time was used to characterize and peak area was used to quantify at 210 nm wavelength.Results:The linear relationships of DMO and DEO were good, r>0.999. The detection limits of DMO and DEO were 0.39 and 0.52 μg/ml, respectively. The quantitative limit was 1.28 μg/ml for DMO and 1.72 μg/ml for DEO. Average desorption efficiency for DMO was 82.40%-92.72%, and DEO was 94.13%-97.69%. The intra-assay precision of DMO was 1.87%-6.18%, and DEO was 2.25%-3.31%. Inter-assay precision of DMO was 3.29%-5.73%, and DEO was 1.38%-2.94%. Average sampling efficiencies were 100% for both DMO and DEO. Breakthrough capacity of DMO was 37.61 mg (200 mg solid adsorbent), DEO was >28.11 mg (200 mg solid adsorbent). Samples should be stored at 4 ℃ for at least 7 days. Conclusion:This method is easy to operate and has strong practicability. All indicators meet the requirements of the specification, and it is suitable for the simultaneous determination of DMO and DEO in the workplace air.

Objective To explore the surgical treatment strategy of acute type A aortic dissection (ATAAD) complicated with Neri type C coronary artery involvement on the basis of detailed classification.Methods Clinical data of 21 cases of ATAAD complicated with Neri type C coronary artery involvement in our hospital from November 2020 to February 2024 were retrospectively analyzed.The dissection involved the coronary artery,and the onset time was less than 1 week.Total aortic arch replacement,descending aorta stent and elephant trunk artificial vessel placement,ascending aorta replacement,and coronary artery management were performed.The treatment of detailed classification and coronary artery was as follows.Seven cases with type C1 ( local damage and rupture of coronary artery opening,partial connection with pseudolumen,and no proximal coronary involvement) were repaired with artificial material"copper coin sample";3 cases with type C2 ( severe avulsion of coronary artery opening,complete connection with pseudolumen,slight proximal involvement of coronary artery,and no sleeve formation) were replaced with 8 mm artificial vessels;11 cases with type C3 ( severe avulsion of coronary artery opening,complete connection with pseudolumen,severe proximal involvement of coronary artery,and sleeve formation) were transplanted by great saphenous vein bypass.Results Two patients died in hospital (all type C3),all of whom had difficulty in cardioversion and were given extracorporeal membrane oxygenation (ECMO) assisted circulation,and passed away on the same day and the second day after surgery,respectively.Aortic and coronary CTA were re-examined in the remaining 19 patients before discharge,and no coronary artery opening stenosis or bridge stenosis was found.Aortic and coronary CTA were re-examined at 6,12,and 18 months after surgery,respectively.The 19 patients were followed up for 6-36 months ( mean,21 months),and there were no cases of coronary artery opening stenosis or bridge stenosis.According to the New York Heart Association (NYHA) functional classification,there were 15 patients with grade Ⅰ and 4 patients with grade Ⅱ.Conclusion The detailed classification of ATAAD combined with Neri type C coronary artery involvement has guiding significance for surgical precision treatment.

Objective To explore the surgical treatment strategy of acute type A aortic dissection (ATAAD) complicated with Neri type C coronary artery involvement on the basis of detailed classification.Methods Clinical data of 21 cases of ATAAD complicated with Neri type C coronary artery involvement in our hospital from November 2020 to February 2024 were retrospectively analyzed.The dissection involved the coronary artery,and the onset time was less than 1 week.Total aortic arch replacement,descending aorta stent and elephant trunk artificial vessel placement,ascending aorta replacement,and coronary artery management were performed.The treatment of detailed classification and coronary artery was as follows.Seven cases with type C1 ( local damage and rupture of coronary artery opening,partial connection with pseudolumen,and no proximal coronary involvement) were repaired with artificial material"copper coin sample";3 cases with type C2 ( severe avulsion of coronary artery opening,complete connection with pseudolumen,slight proximal involvement of coronary artery,and no sleeve formation) were replaced with 8 mm artificial vessels;11 cases with type C3 ( severe avulsion of coronary artery opening,complete connection with pseudolumen,severe proximal involvement of coronary artery,and sleeve formation) were transplanted by great saphenous vein bypass.Results Two patients died in hospital (all type C3),all of whom had difficulty in cardioversion and were given extracorporeal membrane oxygenation (ECMO) assisted circulation,and passed away on the same day and the second day after surgery,respectively.Aortic and coronary CTA were re-examined in the remaining 19 patients before discharge,and no coronary artery opening stenosis or bridge stenosis was found.Aortic and coronary CTA were re-examined at 6,12,and 18 months after surgery,respectively.The 19 patients were followed up for 6-36 months ( mean,21 months),and there were no cases of coronary artery opening stenosis or bridge stenosis.According to the New York Heart Association (NYHA) functional classification,there were 15 patients with grade Ⅰ and 4 patients with grade Ⅱ.Conclusion The detailed classification of ATAAD combined with Neri type C coronary artery involvement has guiding significance for surgical precision treatment.

Objective To compare the effect of continuous saphenous nerve block (SNB)with femoral nerve block (FNB)under multimodal analgesia for early analgesic effect and rehabilitation af-ter total knee replacement (TKA).Methods Sixty patients scheduled to undergo TKA,23 males and 37 females,were randomly divided into two groups:group A (continuous SNB)and group B (contin-uous FNB ).The patients received PCA after surgery by the catheter placed near nerve with ultrasound-guided.The loading dose was 0.5% ropivacaine 25 ml and 0.1 mg epinephrine,back-ground dose was 5 ml/h,bolus dose was 5 ml and the locking time was 20 min.The first time to walk and total steps,the knee joint range of motion,postoperative hospital stay,general anesthetics and additional analgesics dose and the side effects were also recorded.Results The first time to walkand walking distancein group A were better than group B [(25.4±2.1)h vs (34.0±2.7)h,(7.6±1.8) steps vs (3.7±1.3)steps,(P<0.05)].The range of motion in group A was bigger than in group B [12 h:(75.8±4.3)°vs (65.4±4.7)°,24 h:(93.3±4.2)°vs (81.8±4.3)°,48 h:(102.1±4.1)° vs (95.1±2.6)°,P<0.05].The average length of postoperative hospital stay was shorter in group A than in group B [(5.3±1.2)d vs (7.4±1.4)d,P<0.05].The additional analgesics and the side effects were similar between the two groups.Conclusion The continuous SNB combined with multi-modal analgesia was more beneficial to patients with the early postoperative rehabilitation for TKA.

Antimony ; urine ; Flow Injection Analysis ; Spectrometry, Fluorescence ; methods ; Spectrophotometry, Atomic ; methods

Objective To compare the influence of early parenteral nutrition and enteral nutrition on the nutrition,immune,and liver function state of patients with total gastrectomy.Methods A total of 90patients with total gastrectomy in our hospital from July 2010 to October 2012 were selected as research objects,and were randomly divided into group A (early parenteral nutrition group,n =45)and group B(early enteral nutrition group,n =45).The nutrition state indexes,immune state indexes,and liver function indexes of two groups before the intervention and at 3th and 10th day after the intervention were compared.Results The nutrition state indexes[3rd d:TP (68.35 ±3.02)g/L,A (38.94 ±4.69)g/L,PAB (273.54 ±29.68) mg/L,TRF (2.14 ±0.29) g/L,Hb (129.84 ±7.92) g/L;10th d:TP (72.59 ± 3.52)g/L,A (42.31 ±5.49)g/L,PAB (305.57 ±30.95)mg/L,TRF (2.78 ±0.31)g/L,Hb (135.87 ±8.95) g/L],immune state indexes [3rd d:IgA (0.94 ± 0.10) g/L,IgG (9.24 ± 0.63) g/L,IgM (1.51 ±0.14) g/L,RBC-C3bR (10.54 ± 0.52) ％,RBC-ICR (12.21 ± 1.41) ％ ; 10th d:IgA (1.23 ± 0.15) g/L,IgG (10.98 ±0.72)g/L,IgM (1.71 ±0.18) g/L,RBC-C3bR (13.74 ±0.69)％,RBC-ICR (9.27 ±1.05)％],and liver function indexes[3rd d:ALT (32.59 ±3.56)U/L,AST (33.95 ±4.03) U/L,TBIL(12.07± 1.38)μmol/L,GGT (24.03 ±2.59) U/L;10th d:ALT (22.93 ±3.18) U/L,AST (24.84 ±3.29) U/L,TBIL (10.50 ± 0.96) μmol/L,GGT (20.70 ± 2.49) U/L] in group B at 3rd and 10th day after the interventiont were all better than those in group A [3rd d:TP (64.59 ± 2.83)g/L,A (35.53 ±4.37)g/L,PAB (224.96 ±25.50)mg/L,TRF(1.63 ±0.20)g/L,Hb (121.03 ±7.18)g/L,IgA (0.68±0.07)g/L,IgG (7.32 ±0.51)g/L,IgM (1.12 ±0.10)g/L,RBC-C3bR (8.13 ±0.40)％,RBC-ICR (14.59 ±1.54)％,ALT (40.26 ±4.13)U/L,AST (40.95 ±4.26)U/L,TBIL (16.37 ± 1.75)μmol/L,GGT (31.45 ±2.97) U/L;10th d:TP (66.96 ±2.97) g/L,A (36.01 ±4.43) g/L,PAB (241.35 ±26.63) mg/L,TRF (1.86 ± 0.24) g/L,Hb (127.69 ± 7.73) g/L,IgA (0.81 ± 0.08) g/L,IgG (8.54 ±0.55) g/L,IgM (1.28 ± 0.12) g/L,RBC-C3bR (8.52 ± 0.46) ％,RBC-ICR (13.07 ± 1.46) ％,ALT(31.52 ± 3.84) U/L,AST (33.54 ± 3.90) U/L,TBIL (13.21 ± 1.41) μmol/L,GGT (25.39 ± 2.65) U/L],and these indexes in group B at 10th day after the intervention were all significantly better than those at 3rd day after the intervention (all P ＜ 0.05).Conclusions The early enteral nutrition palys an active role in improving the nutrition,immune,and liver function state of patients with total gastrectomy,and it provides the necessary premise for the postoperative rehabilitation of patients.

OBJECTIVETo explore a new method of alleviating graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation (allo-BMT) through selected elimination of mouse alloreactive T cells (ARTC) by Fas-Fas ligand (FasL) passway.

METHODSThe Sca-1(+) early hematopoietic cells (EHCs) were isolated from BALB/c mouse (H-2(d)) bone marrow mononuclear cells (BMMC) by using a high gradient magnetic cell sorting system (MACS), then transferred with exogenous mouse FasL (mFasL) gene by retroviral gene transfecting technique. Afterward the transduced EHCs were expanded in vitro for one week followed by coculture with the spleen cells from BAC mouse (H-2(d) x b) as one-way mixed lymphocyte culture (OWMLC) for 6 days, then the cytotoxicity of treated BAC mouse spleen cells against Na(2)(51)CrO(4) labelling spleen cells from BALB/c mouse was observed.

RESULTSThe Sca-1(+) EHCs were successfully isolated by MACS, with a purity of (89.0 +/- 6.1)%. After transferred with exogenous mFasL gene and expanded for one week, the transferred EHCs in the 6 day OWMLC with the spleen cells from BAC mouse at a ratio of five to one resulted in an obvious inhibition of the BAC mouse spleen cells cytotoxicity against the BALB/c mouse spleen cell at different effector/target ratios as compared to the control group (P < 0.01).

CONCLUSIONThe higher exogenous mFasL-expressing mouse EHCs can deplete ARTC against their own major histocompatibility complex (MHC) antigens in vitro.

Animals ; Antigens, Ly ; immunology ; Fas Ligand Protein ; Female ; Graft vs Host Disease ; immunology ; Hematopoietic Stem Cell Transplantation ; Hematopoietic Stem Cells ; cytology ; immunology ; Membrane Glycoproteins ; genetics ; immunology ; Membrane Proteins ; immunology ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Signal Transduction ; Spleen ; cytology ; immunology ; T-Lymphocytes ; immunology ; Transfection