ReaxFF-Based Molecular Dynamics Study of the Mechanism of the Reaction of N2O4 with H2O.

During long-term storage of the liquid propellant N2O4, it absorbs H2O to form the N2O4(H2O)n system, and this in turn generates HNO3, HNO2, and other substances in the storage tank because of corrosion, which seriously affects the performance of weaponry. In this work, we carried out computational simulations of N2O4 with different masses of water based on ReaxFF, analyzed the reaction intermediates and products, and investigated the mechanism of the reaction of N2O4 with H2O and of N2O4(H2O)n. The results show that the reaction product ω(HNO3+HNO2) undergoes a rapid growth in the early stage of the reaction and then tends toward dynamic equilibrium; the potential energy of the system decreases with the increase of ω(H2O), the reaction rate increases, and the rate of decomposition of HNO2 to form HNO3 increases. When ω(H2O) is 0.2 or 1.0%, the intermediate products are N2O4H2O or N2O4(H2O)2, respectively, and the reaction proceeds along two paths; when ω(H2O) ≥ 2.0%, N2O4(H2O)3 appears as the intermediate product, HNO3 and HNO2 are directly produced in one step, and a stable current loop can be formed within the whole system.

Prevalence and characterization of aminoglycoside resistance gene aph(2")-If-carrying Campylobacter jejuni.

Campylobacter jejuni is recognized as a significant foodborne pathogen, and recent studies have indicated a rising trend of aminoglycosides resistance gene aph(2″)-If among C. jejuni isolates from food-producing animals in China. However, systematic information about aph(2″)-If-positive C. jejuni from food-producing animals and other sources worldwide based on whole-genome analysis remains a knowledge gap. In this study, we aimed to analyze the worldwide distribution, genetic environment and phylogenetic tree of aph(2″)-If by utilizing Whole Genome Sequencing (WGS) data obtained, coupled with information in the GenBank database. A total of 160C. jejuni isolates in the GenBank database and 14C. jejuni isolates in our laboratory carrying aph(2″)-If gene were performed for further analysis. WGS analysis revealed the global distribution of aph(2″)-If among C. jejuni from 6 countries. Multilocus Sequence Typing(MLST) results indicated that 70 STs were involved in the dissemination of aph(2″)-If, with ST10086 being the predominant ST. Whole-genome Multilocus Sequence Typing(wg-MLST) analysis according to times, countries, and origins of C. jejuni isolation further demonstrated a close relationship between aph(2″)-If carrying C. jejuni isolates from farm and food. The findings also revealed the existence of 32 distinct types of genetic environments surrounding aph(2″)-If among these isolates. Notably, Type 30, characterized by the arrangement ISsag10-deoD-ant(9)-hp-hp-aph(2″)-If, emerged as the predominant genetic environment. In conclusion, our analysis provides the inaugural perspective on the worldwide distribution of aph(2″)-If. This resistance gene demonstrates horizontal transferability and regional diffusion in a clonal pattern. The close association observed among aph(2″)-If-positive C. jejuni strains isolated from poultry, food, and clinical environments underscores the potential for zoonotic transmission from these isolates.

Understanding the drying mechanism of straw substrate culture block: Physicochemical properties, pore structure, and drying optimization.

As a new type of agricultural waste block substrate utilization, the initial wet base state of the substrate culture block needs to be dried. Therefore, studying the drying mechanism of substrate culture block is critical. In this study, the substrate culture block in a dry state was taken as the research object. Based on physical and chemical properties, the internal section of the substrate culture block was characterized by scanning electron microscopy and the pore condition of the particles was quantified. The results showed that the internal pore structure was uniform and favorable for plant root growth. Based on the pore structure, pore channel modeling was constructed to investigate the distribution of the internal multiphase medium and to distinguish between channels and pore-blind channels. The applicability of the modeling was verified and discussed. By measuring the drying rate of the substrate culture block and classifying its drying stages as fast speed, constant speed, and slow speed, it is clarified that the forms of moisture existence are bound-state water and free-state water, and the moisture migration is prioritized as surface adsorption water, interparticle water, particle attached water, and capillary water. Innovate a method to quantify the change of pore space in the drying process by pore coefficient ratio to evaluate the drying quality. The results show that when the pore coefficient ratio is about 40 %, its moisture content is 20 %∼30 %, and the drying effect is best at this time. The physical drying test further confirmed the correctness of the conclusion of the drying stage division and water loss law. This study can provide a theoretical reference for the modeling study of the pore structure of the block matrix and the exploration of its drying mechanism.

Repurposing harmaline as a novel approach to reverse tmexCD1-toprJ1-mediated tigecycline resistance against klebsiella pneumoniae infections.

BACKGROUND: A novel plasmid-mediated resistance-nodulation-division (RND) efflux pump gene cluster tmexCD1-toprJ1 in Klebsiella pneumoniae tremendously threatens the use of convenient therapeutic options in the post-antibiotic era, including the "last-resort" antibiotic tigecycline. RESULTS: In this work, the natural alkaloid harmaline was found to potentiate tigecycline efficacy (4- to 32-fold) against tmexCD1-toprJ1-positive K. pneumoniae, which also thwarted the evolution of tigecycline resistance. Galleria mellonella and mouse infection models in vivo further revealed that harmaline is a promising candidate to reverse tigecycline resistance. Inspiringly, harmaline works synergistically with tigecycline by undermining tmexCD1-toprJ1-mediated multidrug resistance efflux pump function via interactions with TMexCD1-TOprJ1 active residues and dissipation of the proton motive force (PMF), and triggers a vicious cycle of disrupting cell membrane integrity and metabolic homeostasis imbalance. CONCLUSION: These results reveal the potential of harmaline as a novel tigecycline adjuvant to combat hypervirulent K. pneumoniae infections.

Transmission of blaNDM in Enterobacteriaceae among animals, food and human.

Despite carbapenems not being used in animals, carbapenem-resistant Enterobacterales (CRE), particularly New Delhi metallo-ß-lactamase-producing CRE (NDM-CRE), are prevalent in livestock. Concurrently, the incidence of human infections caused by NDM-CRE is rising, particularly in children. Although a positive association between livestock production and human NDM-CRE infections at the national level was identified, the evidence of direct transmission of NDM originating from livestock to humans remains largely unknown. Here, we conducted a cross-sectional study in Chengdu, Sichuan Province, to examine the prevalence of NDM-CRE in chickens and pigs along the breeding-slaughtering-retail chains, in pork in cafeterias of schools, and in colonizations and infections from children's hospital and examined the correlation of NDM-CRE among animals, foods and humans. Overall, the blaNDM increases gradually along the chicken and pig breeding (4.70%/2.0%) -slaughtering (7.60%/22.40%) -retail (65.56%/34.26%) chains. The slaughterhouse has become a hotspot for cross-contamination and amplifier of blaNDM. Notably, 63.11% of pork from the school cafeteria was positive for blaNDM. The prevalence of blaNDM in intestinal and infection samples from children's hospitals was 21.68% and 19.80%, respectively. whole genome sequencing (WGS) analysis revealed the sporadic, not large-scale, clonal spread of NDM-CRE along the chicken and pig breeding-slaughtering-retail chain, with further spreading via IncX3-blaNDM plasmid within each stage of whole chains. Clonal transmission of NDM-CRE is predominant in children's hospitals. The IncX3-blaNDM plasmid was highly prevalent among animals and humans and accounted for 57.7% of Escherichia coli and 91.3% of Klebsiella pneumoniae. Attention should be directed towards the IncX3 plasmid to control the transmission of blaNDM between animals and humans.

Research on speed sensorless control strategy of permanent magnet synchronous motor based on fuzzy super-twisting sliding mode observer.

Aiming at the problems of poor adjustment effect, weak anti-disturbance ability, and low robustness of the traditional sliding mode algorithm for permanent magnet synchronous motor speed sensorless, a permanent magnet synchronous motor speed observation method combining super-twisting sliding mode control algorithm and fuzzy control is proposed to accelerate the convergence speed of the system and improve the anti-disturbance ability. Fuzzy rules are used to solve the problem of obtaining the upper bound of the boundary function in the super-twisting algorithm. Moreover, the fuzzy algorithm is used to output the variable sliding mode gain instead of the fixed sliding mode coefficient to improve the system robustness and suppress the jitter. The simulation results show that the overshoot of the control system is 4%, the lag time is not more than 0.003 ms, the speed error is not more than 1%, and the response and adjustment time is not more than 0.02 s. The proposed control strategy improves the tracking accuracy and response speed of the system, suppresses the sliding mode chattering, and enhances the anti-interference ability of the system.

Application of the quality of recovery-40 questionnaire to evaluate the effectiveness of enhanced recovery after surgery protocols in gastric cancer.

Patient reported outcomes is currently considered to be an important supplement to evaluate the effectiveness of enhanced recovery after surgery (ERAS) clinical practice. The Quality of Recovery-40 Questionnaire (QoR-40) is one of the most frequently used and validation tool to assess the subjective feelings of quality of life after surgery. The present study aimed to use the QoR-40 to evaluate the effectiveness of ERAS protocols in gastric cancer from the perspective of patient-reported quality of recovery. The study was designed as a prospective, non-randomized clinical trial, conducted in a single center. Patients in our hospital who were scheduled to undergo radical surgery for gastric cancer were divided into ERAS group and control group (Contr group). The QoR-40 were administered one day before surgery (Baseline) and on postoperative day 1, 3, 6, and 30. The difference in QoR-40 scores between the ERAS and Contr groups was compared by repeated-measures ANOVA. A total of 200 patients completed the study, including 100 patients in the ERAS group and 100 patients in the Contr group. The Baseline time point QoR-40 scores of the ERAS and Contr groups were 179.68 ± 14.46 and 180.12 ± 17.12, respectively, and no significant difference was noted between the two groups (p = 0.845). The postoperative QoR-40 score of the ERAS group was significantly higher than that of the Contr group, and the difference was statistically significant (p = 0.006). This study demonstrated that, in terms of patient-reported quality of recovery, the postoperative recovery effect of ERAS protocols in gastric cancer is significantly better than that of the traditional treatment model.

Femtosecond Laser Inscribed Excessively Tilted Fiber Grating for Humidity Sensing.

We propose a humidity sensor using an excessively tilted fiber grating (Ex-TFG) coated with agarose fabricated using femtosecond laser processing. The processed grating showcases remarkable differentiation between TE and TM modes, achieving an exceptionally narrow bandwidth of approximately 1.5 nm and an impressive modulation depth of up to 15 dB for both modes. We exposed the agarose-coated TFG sensor to various relative humidity levels and monitored the resonance wavelength to test its humidity sensing capability. Our findings demonstrated that the sensor exhibited a rapid response time (2-4 s) and showed a high response sensitivity (18.5 pm/%RH) between the humidity changes and the resonant wavelength shifts. The high sensitivity, linearity, repeatability, low hysteresis, and excellent long-term stability of the TFG humidity sensor, as demonstrated in our experimental results, make it an attractive option for environmental monitoring or biomedical diagnosis.

Carba PBP: a novel penicillin-binding protein-based lateral flow assay for rapid phenotypic detection of carbapenemase-producing Enterobacterales.

Rapid phenotypic detection assays, including Carba NP and its variants, are widely applied for clinical diagnosis of carbapenemase-producing Enterobacterales (CPE). However, these tests are based on the acidification of the pH indicator during carbapenem hydrolysis, which limits test sensitivity and speed, especially for the detection of CPE producing low-activity carbapenem (e.g., OXA-48 variants). Herein, we developed a novel rapid and sensitive CPE detection method (Carba PBP) that could measure substrate (meropenem) consumption based on penicillin-binding protein (PBP). Meropenem-specific PBP was used to develop a competitive lateral flow assay (LFA) for meropenem identification. For the detection of carbapenemase activity, meropenem concentration was optimized using a checkerboard assay. The performance of Carba PBP was evaluated and compared with that of Carba NP using a panel of 94 clinical strains characterized by whole-genome sequencing and carbapenem susceptibility test. The limit of detection of PBP-based LFA for meropenem identification was 7 ng mL-1. Using 10 ng mL-1 meropenem as the substrate, Carba PBP and Carba NP could detect 10 ng mL-1 carbapenemase within 25 min and 1,280 ng mL-1 CPE in 2 h, respectively. The sensitivity and specificity were 100% (75/75) and 100% (19/19) for Carba PBP and 85.3% (64/75) and 100% (19/19) for Carba NP, respectively. When compared with Carba NP, Carba PBP showed superior performance in detecting all the tested CPE strains (including OXA-48-like variants) within 25 min and presented two orders of magnitude higher analytical sensitivity, demonstrating potential for clinical diagnosis of CPE. IMPORTANCE This study successfully achieved the goal of carbapenemase activity detection with both high sensitivity and convenience, offering a convenient lateral flow assay for clinical diagnosis of carbapenemase-producing Enterobacterales.

Liposomal Antibiotic Booster Potentiates Carbapenems for Combating NDMs-Producing Escherichia coli.

Infections caused by Enterobacterales producing New Delhi Metallo-ß-lactamases (NDMs), Zn(II)-dependent enzymes hydrolyzing carbapenems, are difficult to treat. Depriving Zn(II) to inactivate NDMs is an effective solution to reverse carbapenems resistance in NDMs-producing bacteria. However, specific Zn(II) deprivation and better bacterial outer membrane penetrability in vivo are challenges. Herein, authors present a pathogen-primed liposomal antibiotic booster (M-MFL@MB), facilitating drugs transportation into bacteria and removing Zn(II) from NDMs. M-MFL@MB introduces bismuth nanoclusters (BiNCs) as a storage tank of Bi(III) for achieving ROS-initiated Zn(II) removal. Inspired by bacteria-specific maltodextrin transport pathway, meropenem-loaded BiNCs are camouflaged by maltodextrin-cloaked membrane fusion liposome to cross the bacterial envelope barrier via selectively targeting bacteria and directly outer membrane fusion. This fusion disturbs bacterial membrane homeostasis, then triggers intracellular ROS amplification, which activates Bi(III)-mediated Zn(II) replacement and meropenem release, realizing more precise and efficient NDMs producer treatment. Benefiting from specific bacteria-targeting, adequate drugs intracellular accumulation and self-activation Zn(II) replacement, M-MFL@MB rescues all mice infected by NDM producer without systemic side effects. Additionally, M-MFL@MB decreases the bacterial outer membrane vesicles secretion, slowing down NDMs producer's transmission by over 35 times. Taken together, liposomal antibiotic booster as an efficient and safe tool provides new strategy for tackling NDMs producer-induced infections.

Tigecycline Sensitivity Reduction in Escherichia coli Due to Widely Distributed tet(A) Variants.

Despite scattered studies that have reported mutations in the tet(A) gene potentially linked to tigecycline resistance in clinical pathogens, the detailed function and epidemiology of these tet(A) variants remains limited. In this study, we analyzed 64 Escherichia coli isolates derived from MacConkey plates supplemented with tigecycline (2 µg/mL) and identified five distinct tet(A) variants that account for reduced sensitivity to tigecycline. In contrast to varied tigecycline MICs (0.25 to 16 µg/mL) of the 64 tet(A)-variant-positive E. coli isolates, gene function analysis confirmed that the five tet(A) variants exhibited a similar capacity to reduce tigecycline sensitivity in DH5α carrying pUC19. Among the observed seven non-synonymous mutations, the V55M mutation was unequivocally validated for its positive role in conferring tigecycline resistance. Interestingly, the variability in tigecycline MICs among the E. coli strains did not correlate with tet(A) gene expression. Instead, a statistically significant reduction in intracellular tigecycline concentrations was noted in strains displaying higher MICs. Genomic analysis of 30 representative E. coli isolates revealed that tet(A) variants predominantly resided on plasmids (n = 14) and circular intermediates (n = 13). Within China, analysis of a well-characterized E. coli collection isolated from pigs and chickens in 2018 revealed the presence of eight tet(A) variants in 103 (4.2%, 95% CI: 3.4-5.0%) isolates across 13 out of 17 tested Chinese provinces or municipalities. Globally, BLASTN analysis identified 21 tet(A) variants in approximately 20.19% (49,423/244,764) of E. coli genomes in the Pathogen Detection database. These mutant tet(A) genes have been widely disseminated among E. coli isolates from humans, food animals, and the environment sectors, exhibiting a growing trend in tet(A) variants over five decades. Our findings underscore the urgency of addressing tigecycline resistance and the underestimated role of tet(A) mutations in this context.

Rapid ultra-sensitive nucleic acid detection using plasmonic fiber-optic spectral combs and gold nanoparticle-tagged targets.

Nucleic acid (NA) is a widely-used biomarker for viruses. Accurate quantification of NA can provide a reliable basis for point-of-care diagnosis and treatment. Here, we propose a tilted fiber Bragg grating (TFBG)-based plasmonic fiber-optic spectral comb for fast response and ultralow limit NA detection. The TFBG is coated with a gold film which enables excitation of surface plasmon resonance (SPR), and single-stranded probe NAs with known base sequences are assembled on the gold film. To enhance sensitivity of refractive index (RI) for sensing a chosen combination of probe and target NAs around the TFBG surface, gold nanoparticles (AuNPs) are bonded to the target NA molecules as "RI-labels". The NA combination-induced aggregation of AuNPs induces significant spectral responses in the TFBG that would be below the detection threshold for the NAs in the absence of the AuNPs. The proposed TFBG-SPR NA sensor shows a fast response time of 30 s and an ultra-wide NA detection range from 1 × 10-18 mol/L to 1 × 10-7 mol/L. In the NA concentration range of 1 × 10-12 mol/L (1 pM) to 105 pM, an ultra-high sensitivity of 1.534 dB/lg(pM) is obtained. The sensor achieves an ultra-low limit of detection down to 1.0 × 10-18 mol/L (1 aM), which is more than an order of magnitude lower than the previous reports. The proposed sensor not only shows potentials in practical applications of NA detection, but also provides a new way for TFBG-SPR biochemical sensors to achieve higher RI sensitivity.

Terahertz angle-independent photonic bandgap in a one-dimensional photonic crystal containing InSb-based hyperbolic metamaterials: erratum.

This erratum corrects the typing errors in Eq. (6) and the caption of Fig. 4 of the original paper, Appl. Opt.61, 7677 (2022).APOPAI0003-693510.1364/AO.470923 The correction does not affect the results of the original paper.

Dihydroartemisinin inhibits plasmid transfer in drug-resistant Escherichia coli via limiting energy supply.

Conjugative transfer of antibiotic resistance genes (ARGs) by plasmids is an important route for ARG dissemination. An increasing number of antibiotic and nonantibiotic compounds have been reported to aid the spread of ARGs, highlighting potential challenges for controlling this type of horizontal transfer. Development of conjugation inhibitors that block or delay the transfer of ARG-bearing plasmids is a promising strategy to control the propagation of antibiotic resistance. Although such inhibitors are rare, they typically exhibit relatively high toxicity and low efficacy in vivo and their mechanisms of action are inadequately understood. Here, we studied the effects of dihydroartemisinin (DHA), an artemisinin derivative used to treat malaria, on conjugation. DHA inhibited the conjugation of the IncI2 and IncX4 plasmids carrying the mobile colistin resistance gene ( mcr-1) by more than 160-fold in vitro in Escherichia coli, and more than two-fold (IncI2 plasmid) in vivo in a mouse model. It also suppressed the transfer of the IncX3 plasmid carrying the carbapenem resistance gene bla NDM-5 by more than two-fold in vitro. Detection of intracellular adenosine triphosphate (ATP) and proton motive force (PMF), in combination with transcriptomic and metabolomic analyses, revealed that DHA impaired the function of the electron transport chain (ETC) by inhibiting the tricarboxylic acid (TCA) cycle pathway, thereby disrupting PMF and limiting the availability of intracellular ATP for plasmid conjugative transfer. Furthermore, expression levels of genes related to conjugation and pilus generation were significantly down-regulated during DHA exposure, indicating that the transfer apparatus for conjugation may be inhibited. Our findings provide new insights into the control of antibiotic resistance and the potential use of DHA.

Case report: Cardiac metastatic uterine intravenous leiomyomatosis excision with extracorporeal venous shunt under the guidance of 3-dimensional printing.

Intravenous leiomyomatosis (IVL) is relatively rare, and the incidence of cardiac IVL is even lower. The case report introduces a 48-year-old woman with two episodes of syncope in 2021. Echocardiography showed a cord-like mass in the inferior vena cava (IVC), right atrium (RA), right ventricle (RV) and pulmonary artery. Computed tomography venography and magnetic resonance imaging showed strips in RA, RV, IVC, right common iliac vein, and internal iliac vein, as well as a round-like mass in the right uterine adnexa. Combined with the patient's prior surgical history and rare anatomical structures, surgeons used cardiovascular 3-dimensional (3D) printing technology to create patient-specific preoperative 3D printed model. The model could help surgeons to visually and accurately understand the size of IVL and its relationship to adjacent tissues. Finally, surgeons successfully performed a concurrent transabdominal resection of cardiac metastatic IVL and adnexal hysterectomy with off-cardiopulmonary bypass. Preoperative evaluation and guidance of 3D printing may play a critical role to ensure this surgery for the patient with rare anatomical structures and high surgical risk. Clinical Trial Registration: [ClinicalTrials.gov], Protocol Registration System [NCT02917980].

Correction: A redshifted photonic bandgap and wide-angle polarization selection in an all-hyperbolic-metamaterial one-dimensional photonic crystal.

Correction for 'A redshifted photonic bandgap and wide-angle polarization selection in an all-hyperbolic-metamaterial one-dimensional photonic crystal' by Feng Wu et al., Phys. Chem. Chem. Phys., 2023, 25, 10785-10794, https://doi.org/10.1039/D3CP00280B.

Rydberg state dynamics and fragmentation mechanism of N,N,N',N'-tetramethylmethylenediamine.

The non-adiabatic relaxation processes and the fragmentation dynamics of Rydberg-excited N,N,N',N'-tetramethylmethylenediamine (TMMDA) are investigated using femtosecond time-resolved photoelectron imaging and time-resolved mass spectroscopy. Excitation at 208 nm populates TMMDA in a charge-localized 3p state. Rapid internal conversion (IC) to 3s produces two charge-delocalized conformers with independent time constants and distinct population ratios. As the system explores the 3s potential surface, the structural evolution continues on a 1.55 ps timescale, followed by a slower (12.1 ps) relaxation to the ground state. A thorough comparison of the time-dependent mass and photoelectron spectra suggests that ionization out of the 3p state ends up with the parent ion, the vibrational energy of which is insufficient for the bond cleavage. On the contrary, by virtue of the additional energy acquired by IC from 3p, the internal energy deposited in 3s is available to break the C-N bond, leading to the fragment ion. The fragmentation is found to occur on the ion surface instead of the Rydberg surface.

Variable ratio blue/red upconversion in Yb3+-Tm3+ codoped fluorosilicate glasses.

Simultaneous blue-red emission in a fiber pumped by a single wavelength source is perceived as a great challenge because of the large energy difference of the emitted photons. This Letter reports the dependence of the blue-to-red upconversion (UC) emission ratio in Yb3+-Tm3+ codoped fluorosilicate glasses (FSGs) under the excitation of a 980-nm laser on the host glass silica content. Photoluminescence spectra and SEM-EDS are used to clarify the UC mechanism, indicating that the probability of the cross-relaxation (CR) process 1G4 + 3F2→3H6 + 3F4 is key to the dominance of the blue or red emissions. This research can provide a new platform for variable UC luminescence.

Terahertz asymmetric metallic hole arrays with polarization-independent quasi-bound states in the continuum for membrane sensing.

Resonances with both high-quality factor and polarization-independent characteristics are highly desirable for terahertz (THz) sensing. Here, THz sensors based on asymmetric metallic hole arrays (AMHAs) are experimentally demonstrated. Such sensors consisting of four-hole arrays support polarization-independent quasi-bound states in the continuum (BICs). The induced quasi-BIC presents a quality factor exceeding 2000, which enables enhanced sensing for thin membranes. Results show that the frequency shift is 97.5 GHz for the 25-µm thick polyimide (PI), corresponding to a sensitivity of 147.7 GHz/RIU. The sensing performance strongly relates to the enhanced field originating from sharp quasi-BICs. A maximum field enhancement of 15.88 in contrast to the incident field is achieved. When the PI thickness is large than the decay length of enhanced fields, the interaction strength of field-PI becomes weak, resulting in a saturation effect for the shift of quasi-BICs. The proposed sensor possessing polarization-independent quasi-BICs has great potential for practical sensing applications in real-time chemical and biomolecular.

Application of a New M-shaped High Tibial Osteotomy Method: A Technical Note.

High tibial osteotomy (HTO) is used as an alternative to total knee arthroplasty in young patients with knee osteoarthritis. In the conventional HTO, if the distraction distance is large, the osteotomy section will be significantly separated, forming a large bone defect gap, which may lead to delayed healing or even nonunion. We treated a series of 10 patients with medial knee osteoarthritis by a novel M-shaped high tibial osteotomy. This helped to improve greater contact of cortical sections and rapid healing of the osteotomy break. Over a mean follow-up period of 8.5 months (range, 6.0-12.0 months), all patients achieved bone union. None of the patients showed complications such as nonunion or infection. The novel M-shaped HTO procedure can reduce the probability of delayed union/nonunion and avoid the complications associated with bone grafting. Hence, this technique may be an effective alternative for the HTO.