An analysis of differences in Carbapenem-resistant Enterobacterales in different regions: a multicenter cross-sectional study.

OBJECTIVE: This study aimed to explore the characteristics of carbapenem-resistant Enterobacterales (CRE) patients in the intensive care unit (ICU) in different regions of Henan Province to provide evidence for the targeted prevention and treatment of CRE. METHODS: This was a cross-sectional study. CRE screening was conducted in the ICUs of 78 hospitals in Henan Province, China, on March 10, 2021. The patients were divided into provincial capital hospitals and nonprovincial capital hospitals for comparative analysis. RESULTS: This study involved 1009 patients in total, of whom 241 were CRE-positive patients, 92 were in the provincial capital hospital and 149 were in the nonprovincial capital hospital. Provincial capital hospitals had a higher rate of CRE positivity, and there was a significant difference in the rate of CRE positivity between the two groups. The body temperature; immunosuppressed state; transfer from the ICU to other hospitals; and use of enemas, arterial catheters, carbapenems, or tigecycline at the provincial capital hospital were greater than those at the nonprovincial capital hospital (P < 0.05). However, there was no significant difference in the distribution of carbapenemase strains or enzymes between the two groups. CONCLUSIONS: The detection rate of CRE was significantly greater in provincial capital hospitals than in nonprovincial capital hospitals. The source of the patients, invasive procedures, and use of advanced antibiotics may account for the differences. Carbapenem-resistant Klebsiella pneumoniae (CR-KPN) was the most prevalent strain. Klebsiella pneumoniae carbapenemase (KPC) was the predominant carbapenemase enzyme. The distributions of carbapenemase strains and enzymes were similar in different regions.

Simulating the HeI photoelectron spectrum of Cl2O with new full-dimensional adiabatic potential energy surfaces of Cl2O(X̃1A1), Cl2O+(X̃2B1), and Cl2O+(C̃2A2) and a three-state diabatic potential energy matrix of Cl2O+(Ã2B2, B̃2A1, and 22A1): a quantum mechanical study.

To interpret the HeI photoelectron spectrum of Cl2O (involving four lowest electronic states of Cl2O+), in this work we first constructed the associated adiabatic full-dimensional potential energy surfaces (PESs) of Cl2O(X̃1A1), Cl2O+(X̃2B1), and Cl2O+(C̃2A2) and a diabatic potential energy matrix (PEM) of Cl2O+(Ã2B2, B̃2A1, and 22A1) using the explicitly correlated internally contracted multi-reference configurational interaction with Davidson correction (MRCI-F12+Q) and neural network methods. Particularly for the Ã2B2, B̃2A1, and 22A1 states of Cl2O+ coupled in terms of conical intersection, their diabatization is achieved by the neural network approach based merely on the associated adiabatic energies. With the help of newly constructed adiabatic PESs and the diabatic PEM, the HeI photoelectron spectrum of Cl2O is further computed quantum mechanically. The calculated photoelectron spectrum is found to be in good accord with experiment. The mode specificity in the HeI photoelectron bands of Cl2O is analyzed in detail.

Basilar invagination without atlantoaxial dislocation: treatment by correction of clivus canal angle with interfacet distraction and fixation.

BACKGROUND: This study reports on the surgical technique used and clinical outcomes obtained during the treatment of basilar invagination (BI) without atlantoaxial dislocation (AAD) through the correction of the clivus canal angle (CCA) using interfacet distraction and fixation. METHODS: Nineteen cases with BI without AAD treated by the correction of the clivus canal angle were retrospectively analyzed. Pre- and postoperative computed tomography scans and three-dimensional reconstruction views were obtained to measure the size of the CCA, pB-C2 distance, and degree of BI. Chiari malformation and syringomyelia were evaluated by magnetic resonance imaging (MRI). The clinical outcomes for all patients were measured using the Japanese Orthopedic Association (JOA) scale. The CCA was corrected by using interfacet distraction and fixation techniques. The Wilcoxon test was used to compare pre- and postoperative measurements. RESULTS: All the patients were followed up for 24.95 ± 5.22 months (range 12-36 months); no patient suffered intraoperative nerve or vascular injury. Clinical symptoms improved in 17 patients (89.5%). The mean JOA score increased from 12.32 ± 1.89 to 14.37 ± 1.30 (Z = -3.655, P < 0.001). The mean CCA improved from 129.34 ± 8.52° preoperatively to 139.75 ± 8.86° postoperatively (Z = -3.824, P < 0.001). The mean pB-C2 decreased from 7.47 ± 2.21 to 5.68 ± 3.13 (Z = -3.060, P = 0.002). Syringomyelia was significantly reduced in 10 out of 13 patients by the first follow-up year. All patients achieved bony fusion. CONCLUSION: Posterior interfacet distraction and fixation to correct the CCA is a feasible and effective method for treating BI without AAD.

Population-based meta-analysis of chloroquine: informing chloroquine pharmacokinetics in COVID-19 patients.

AIMS: Chloroquine (CQ) has been repurposed to treat coronavirus disease 2019 (COVID-19). Understanding the pharmacokinetics (PK) in COVID-19 patients is essential to study its exposure-efficacy/safety relationship and provide a basis for a possible dosing regimen optimization. SUBJECT AND METHODS: In this study, we used a population-based meta-analysis approach to develop a population PK model to characterize the CQ PK in COVID-19 patients. An open-label, single-center study (ethical review approval number: PJ-NBEY-KY-2020-063-01) was conducted to assess the safety, efficacy, and pharmacokinetics of CQ in patients with COVID-19. The sparse PK data from 50 COVID-19 patients, receiving 500 mg CQ phosphate twice daily for 7 days, were combined with additional CQ PK data from 18 publications. RESULTS: A two-compartment model with first-order oral absorption and first-order elimination and an absorption lag best described the data. Absorption rate (ka) was estimated to be 0.559 h-1, and a lag time of absorption (ALAG) was estimated to be 0.149 h. Apparent clearance (CL/F) and apparent central volume of distribution (V2/F) was 33.3 l/h and 3630 l. Apparent distribution clearance (Q/F) and volume of distribution of peripheral compartment (Q3/F) were 58.7 l/h and 5120 l. The simulated CQ concentration under five dosing regimens of CQ phosphate were within the safety margin (400 ng/ml). CONCLUSION: Model-based simulation using PK parameters from the COVID-19 patients shows that the concentrations under the currently recommended dosing regimen are below the safety margin for side-effects, which suggests that these dosing regimens are generally safe. The derived population PK model should allow for the assessment of pharmacokinetics-pharmacodynamics (PK-PD) relationships for CQ when given alone or in combination with other agents to treat COVID-19.

The Use of Chlorhexidine as a Skin Preparation on the Head and Neck: A Systematic Review of Ocular and Ototoxicity.

BACKGROUND: Chlorhexidine gluconate is one of the most effective surgical preparations, but it has known potential ocular and ototoxicity. OBJECTIVE: To review reported cases of ocular and ototoxicity caused by chlorhexidine and summarize the clinical situations in which chlorhexidine toxicity occurred. METHODS: We performed a systematic review of PubMed and the Web of Science. RESULTS: Fourteen cases reported sensorineural hearing loss from chlorhexidine instilled into the ear. Of the 38 cases of ocular toxicity, 8 cases were caused by direct instillation in the eye and 17 involved periocular surgical preparation. In the remaining cases, the area prepped was less defined. Seven cases involved preparation of the face, 1 for the scalp, 2 cases were drips from distant sites, and 3 cases did not specify the means of exposure. CONCLUSION: The vast majority of toxicity occurred in patients undergoing general anesthesia and was rarely seen in situations where surgery was performed by dermatologists. Ultimately, it should be up to the individual physician to decide whether chlorhexidine is the best choice for a particular outpatient procedure.

Physiologically based pharmacokinetic model of renally cleared antibacterial drugs in Chinese renal impairment patients.

To preliminarily develop physiologically based population models for Chinese renal impairment patients and to evaluate the prediction performance of new population models by renally cleared antibacterial drugs. First, demographic data and physiological parameters of Chinese renal impairment patients were collected, and then the coefficients of the relative demographic and physiological equation were recalibrated to construct the new population models. Second, drug-independent parameters of ceftazidime, cefodizime, vancomycin, and cefuroxime were collected and verified by Chinese healthy volunteers, Caucasian healthy volunteers, and Caucasian renal impairment population models built in Simcyp. Finally, the newly developed population models were applied to predict the plasma concentration of four antibacterial drugs in Chinese renal impairment patients. The new physiologically based pharmacokinetic (PBPK) population models can predict the main pharmacokinetic parameters, including area under the plasma concentration-time curve extrapolated to infinity (AUCinf ), renal clearance (CLr ), and peak concentration (Cmax ), of ceftazidime, cefodizime, vancomycin, and cefuroxime following intravenous administrations with less than twofold error in mild, moderate, and severe Chinese renal impairment patients. The accuracy and precision of the predictions were improved compared with the Chinese healthy volunteers and Caucasian renal impairment population models. The PBPK population models were preliminarily developed and the first-step validation results of four antibacterial drugs following intravenous administration showed acceptable accuracy and precision. The population models still need more systematic validation by using more drugs and scenarios in future studies to support their applications on dosage recommendation for Chinese renal impairment patients.

Movable Valley Switch Driven by Berry Phase in Bilayer-Graphene Resonators.

Berry phase, the geometric phase accumulated over a closed loop in parameter space during an adiabatic cyclic evolution, has been demonstrated to play an important role in many quantum systems since its discovery. In gapped Bernal bilayer graphene, the Berry phase can be continuously tuned from zero to 2π, which offers a unique opportunity to explore the tunable Berry phase on physical phenomena. Here, we report experimental observation of Berry-phase-induced valley splitting and crossing in movable bilayer-graphene p-n junction resonators. In our experiment, the resonators are generated by combining the electric field of a scanning tunneling microscope tip with the gap of bilayer graphene. A perpendicular magnetic field changes the Berry phase of the confined bound states in the resonators from zero to 2π continuously and leads to the Berry phase difference for the two inequivalent valleys in the bilayer graphene. As a consequence, we observe giant valley splitting and unusual valley crossing of the lowest bound states. Our results indicate that the bilayer-graphene resonators can be used to manipulate the valley degree of freedom in valleytronics.

A modified microsurgical interfacet release and direct distraction technique for management of congenital atlantoaxial dislocation: technical note.

Various techniques have been used for management of congenital atlantoaxial dislocation. Recently, the reduction of atlantoaxial dislocation through a single posterior approach has attracted more and more attention. Here, we present a modified technique including direct interfacet release and distraction between C1 and C2 by a specially designed distractor, posterior internal fixation and bone graft fusion. The illustrated technique was performed in 15 consecutive patients, and the outcomes were recorded and analyzed. Follow-up ranged from 12 to 26 months. Clinical symptoms improved in 14 patients (93.3%) and were stable in 1 patient (6.7%). Radiologically, 60-100% reduction was achieved in 13 patients (86.6%). Bone fusion was obtained in all patients at 12 months after the operation. The two-tailed Wilcoxon signed-rank test was used to analyze the preoperative and postoperative Japanese Orthopedic Association scores (JOA), atlas-dens interval (ADI), and cervicomedullary angle (CMA) (P < 0.001). Our results suggested that this direct interfacet release and distraction technique with a specially designed C1-2 distractor can provide a definite effective C1-2 facet distraction and odontoid process restoration through a single posterior approach.

The Applications of Medical Tattooing in the Head and Neck Region.

Medical tattooing has been used in various circumstances. In this review, the authors focus on the utilization of medical tattooing in the head and neck region as a minimally invasive alternative to corrective surgeries. It is mostly used to camouflage noticeable surgical scars on scalp, face, and perioral areas. Its use has also been described in cases of concealing depigmentation or hypopigmentation, hair loss, postirradiation telangiectasia, and congenital vascular malformation. These procedures are well-tolerated and safe. Its effects are long-lasting and satisfactory, leading to improvement in self-esteem and increased quality of life in treated patients. The limitations of medical tattooing in such uses include high technical requirement, color fading and alteration, unpredictable outcomes in scarred tissue, and potential cutaneous reactions. It also carries a risk of infection, albeit very low due to standardized sterilization process in a medical setting. The authors conclude that medical tattooing in the head and neck region may serve as an excellent option for patients who seek for cosmetic improvement in their deformities and/or discoloration but would prefer to avoid surgery.

Risk factors predicting a higher grade of subarachnoid haemorrhage in small ruptured intracranial aneurysm (< 5 mm).

AIM: To identify the risk factors for clinical and radiographic grades of subarachnoid haemorrhage (SAH) in small (< 5 mm) intracranial aneurysms (SIAs). MATERIAL AND METHODS: We retrospectively analysed patients with SIAs treated in our centre between February 2009 and June 2018. The clinical status was graded using the Hunt and Hess (H&H) score and the radiological severity of SAH was graded by Fisher grades (FG). The risk factors were determined using multivariate logistic regression analysis. RESULTS: A total of 160 patients with ruptured SIAs (< 5 mm) were included. In univariate analysis, smoking (P = 0.007), alcohol use (P = 0.048), aspirin use (P = 0.001), and higher size ratio (SR) (P = 0.001) were significantly associated with a higher H&H grade (3-5) in SIAs; and smoking (P = 0.019), aspirin use (P = 0.031), inflow angle < 90 degrees (P = 0.011), and aneurysm size (P = 0.039) were significantly associated with a higher FG score (3-4). In the adjusted multivariate analysis, previous SAH (OR, 12.245, 95% CI, 2.261-66.334, P = 0.004), aspirin use (OR, 4.677, 95% CI, 1.392-15.718, P = 0.013), alcohol use (OR, 3.392, 95% CI, 1.146-10.045, P = 0.027), inflow angle < 90 (OR, 3.881, 95% CI, 1.273-11.831, P = 0.017), and higher SR (OR, 6.611, 95% CI, 2.235-19.560, P = 0.001) were independent risk factors for a higher H&H grade in ruptured SIAs; smoking (OR, 2.157, 95% CI, 1.061-4.384, P = 0.034), and inflow angle < 90 degrees (OR, 2.603, 95% CI, 1.324-5.115, P = 0.006) were independent risk factors for a higher FG (3-4). CONCLUSIONS: This study revealed that inflow angle < 90 degrees and size ratio, but not absolute size, may highly predict poorer grade of SAH in SRA. Aspirin use, previous SAH, and alcohol use were significantly associated with a higher H&H grade in ruptured SIAs, and smoking was a significant predictor of poorer FG.

SMS2D designs as starting points for lens optimization.

Traditional imaging design methods can often be ineffective when designing aspheric systems because of the large number of optimization parameters and lack of a good starting point. They are often trapped in a poor local minimum and it can be highly time-consuming to find a good solution in a bumpy design landscape. The simultaneous multiple surface (SMS) method can significantly shorten the time and effort needed to find a desired solution by providing a starting point to optimize close to a good local minimum. We investigate here two design examples and compare them with similar designs obtained via traditional design approaches, as well as global optimization. In the examples considered here, the SMS method combined with a shorter optimization leads to an optimal design.

Rational Design of Short Peptide-Based Hydrogels with MMP-2 Responsiveness for Controlled Anticancer Peptide Delivery.

Molecular self-assembly makes it feasible to harness the structures and properties of advanced materials via initial molecular design. To develop short peptide-based hydrogels with stimuli responsiveness, we designed here short amphiphilic peptides by engineering protease cleavage site motifs into self-assembling peptide sequences. We demonstrated that the designed Ac-I3SLKG-NH2 and Ac-I3SLGK-NH2 self-assembled into fibrillar hydrogels and that the Ac-I3SLKG-NH2 hydrogel showed degradation in response to MMP-2 but the Ac-I3SLGK-NH2 hydrogel did not. The cleavage of Ac-I3SLKG-NH2 into Ac-I3S and LKG-NH2 was found to be mechanistically responsible for the enzymatic degradation. Finally, when an anticancer peptide G(IIKK)3I-NH2 (G3) was entrapped into Ac-I3SLKG-NH2 hydrogels, its release was revealed to occur in a "cell-demanded" way in the presence of HeLa cells that overexpress MMP-2, therefore leading to a marked inhibitory effect on their growth on the gels.

Crohn disease-associated neutrophilic urticarial dermatosis: report and literature review of neutrophilic urticarial dermatosis.

Neutrophilic urticarial dermatosis (NUD) is a useful diagnostic term for urticarial lesions that are less pruritic and more painful than conventional urticaria. The histopathologic features include neutrophilic infiltrates in the interstitial dermis with a higher density than idiopathic urticaria. NUD has been associated with several systemic conditions, which are predominantly autoimmune and autoinflammatory in nature. A woman with Crohn disease who developed NUD is described. Literature reports of other conditions in which neutrophilic urticarial dermatosis have been observed are also reviewed and summarized. NUD has not only been described in the setting of inflammatory bowel disease, but also in patients who have systemic lupus erythematosus, adult-onset Still disease, and IgA gammopathy. NUD is usually associated with an underlying disease. Therapeutic agents that target neutrophils (such as dapsone and colchicine) and antagonists to interleukin-1 receptor (such as anakinra) may be effective modalities for affected patients. NUD can be added to the list of dermatologic manifestations associated with systemic inflammation, particularly inflammatory bowel disease.

Synthesis, bioactivity and structure-activity relationships of new 2-aryl-8-OR-3,4-dihydroisoquinolin-2-iums salts as potential antifungal agents.

As our continuing research on antifungal dihydroisoquinolin-2-ium salts, forty 2-aryl-8-OR-3,4-dihydroisoquinolin-2-ium bromides were synthesized and characterized by spectroscopic analysis. By using the mycelium growth rate method, the compounds were evaluated for antifungal activity against three plant pathogenic fungi and structure-activity relationships (SAR) were derived. The vast majority of the compounds displayed the medium to high activity with inhibition rates of 50-100% at 150µM. About half of the compounds were more active than their natural model compounds sanguinarine and chelerythrine for all the fungi, and part or most of them were more active than positive drugs thiabendazole and azoxystrobin. SAR analysis showed that both substitution patterns of the C-ring and the type of 8-OR group significantly influenced the activity. Thus, a series of new title compounds with excellent antifungal potency emerged.

One-dimensional searches for finding new lens design solutions efficiently.

A special structure is present in the lens design landscape that makes it different from a general global optimization problem: many local minimums are closely related to minimums of simpler problems and can therefore be found by decomposing the search for them in simple steps. We show here that in the design landscape of a wide-angle pinhole lens and in closely related optimization landscapes, all good local minimums found by other methods can be obtained easily with a succession of one-dimensional searches starting from simpler systems. By replacing high-dimensional searches with a succession of one-dimensional searches, the design efficiency can be increased significantly. By combining this method with conventional design methods, the wide-angle pinhole lens can be designed starting from a single lens.

Transcriptional and functional responses of Escherichia coli O157:H7 growing in the lettuce rhizoplane.

Lettuce and spinach are increasingly implicated in foodborne illness outbreaks due to contamination by Escherichia coli O157:H7. While this bacterium has been shown to colonize and survive on lettuce leaf surfaces, little is known about its interaction with the roots of growing lettuce plants. In these studies, a microarray analyses, mutant construction and confocal microscopy were used to gain an understanding of structure and function of bacterial genes involved in the colonization and growth of E. coli O157:H7 on lettuce roots. After three days of interaction with lettuce roots, 94 and 109 E. coli O157:H7 genes were significantly up- and down-regulated at least 1.5 fold, respectively. While genes involved in biofilm modulation (ycfR and ybiM) were significantly up-regulated, 40 of 109 (37%) of genes involved in protein synthesis were significantly repressed. E. coli O157:H7 was 2 logs less efficient in lettuce root colonization than was E. coli K12. We also unambiguously showed that a ΔycfR mutant of E. coli O157:H7 was unable to attach to or colonize lettuce roots. Taken together these results indicate that bacterial genes involved in attachment and biofilm formation are likely important for contamination of lettuce plants with Shiga toxin-producing E. coli strains.

Synthesis and in vitro antifungal activities of new 2-aryl-6,7-methylenedioxy-3,4-dihydroisoquinolin-2-ium bromides.

2-Aryl-3,4-dihydroisoquinolin-2-iums might be considered as a class of simple analogues of natural quaternary benzo[c]phenanthridine alkaloids. In this paper, 26 new 2-aryl-6,7-methylenedioxy-3,4-dihydroisoquinolin-2-ium bromides with various substituents in N-aromatic ring were synthesized from commercially available 1,3-benzodioxole in good to excellent yields. All the compounds were elucidated by MS, high resolution (HR)-MS, IR, (1)H- and (13)C-NMR analysis, and evaluated for antifungal activities in vitro against Alternaria alternate, Curvularia lunata and Fusarium oxysporum sp. niveum at 50 µg/mL. Most of the compounds showed higher activities against all the test fungi than their natural model compounds sanguinarine and chelerythrine. For A. alternate and Curvularia lunata, most of them were also more active than thiabendazole, a commercial fungicide standard. The structure-activity relationship indicated that the substituent in N-aromatic ring and its position had significant effect on the activity. The general trend was that halogen atoms and CF3 remarkably enhanced the activity while CH3 and OCH3 decreased the activity. Generally, o-substituted isomers were more active than m- and p-substituted isomer. The present results suggest that the title compounds are potential for the development of new isoquinoline antimicrobial agents.

Synthesis of 2-aryl-3,4-dihydroisoquinolin-2-ium bromides and their in vitro acaricidal activity against Psoroptes cuniculi.

By employing sanguinarine, a natural active quaternary isoquinoline alkaloid, as a model molecule, a series of structurally simple quaternary 2-aryl-3,4-dihydroisoquinolin-2-ium compounds were designed and synthesized and evaluated for in vitro acaricidal activity against P. cuniculi. A new approach towards the title compounds was developed with isochroman as starting material. The results showed that 22 of 24 tested compounds displayed the activity in varying degrees at 0.4 mg/mL. Fourteen compounds were significantly more effective than ivermectin, a standard acaricide, and 6-methoxy dihydrosanguinarine, a derivative of sanguinarine (p<0.05). And their comprehensive relative activity was 1.4 to 16.5 times than that of ivermectin and 1.5 to 18.8 times than that of 6-methoxy dihydrosanguinarine. The structure-activity relationship indicated that the introduction of a substituent to N-benzene ring, especially halogen atom and trifluoromethyl group, led to great improvement of the activity. The position of fluorine atom, methyl group and hydroxyl group made very significant effects on the activity. It was concluded that 2-aryl-3,4-dihydroisoquinolin-2-iums are very promising candidates for the development of new isoquinoline acaricidal agents.

2-(Substituted phenyl)-3,4-dihydroisoquinolin-2-iums as novel antifungal lead compounds: biological evaluation and structure-activity relationships.

The title compounds are a class of structurally simple analogues of quaternary benzo[c]phenanthridine alkaloids (QBAs). In order to develop novel QBA-like antifungal drugs, in this study, 24 of the title compounds with various substituents on the N-phenyl ring were evaluated for bioactivity against seven phytopathogenic fungi using the mycelial growth rate method and their SAR discussed. Almost all the compounds showed definite activities in vitro against each of the test fungi at 50 µg/mL and a broad antifungal spectrum. In most cases, the mono-halogenated compounds 2-12 exhibited excellent activities superior to the QBAs sanguinarine and chelerythrine. Compound 8 possessed the strongest activities on each of the fungi with EC50 values of 8.88-19.88 µg/mL and a significant concentration-dependent relationship. The SAR is as follows: the N-phenyl group is a high sensitive structural moiety for the activity and the characteristics and position of substituents intensively influence the activity. Generally, electron-withdrawing substituents remarkably enhance the activity while electron-donating substituents cause a decrease of the activity. In most cases, ortha- and para-halogenated isomers were more active than the corresponding m-halogenated isomers. Thus, the title compounds emerged as promising lead compounds for the development of novel biomimetic antifungal agrochemicals. Compounds 8 and 2 should have great potential as new broad spectrum antifungal agents for plant protection.

Interfacet Distraction for Type B-Basilar Invagination Assisted by a Novel Sliding-Traction Head Holder: 2-Dimensional Operative Video.

Type B basilar invagination (BI) refers to odontoid process prolapse into skull base without dislocation, which is often associated with Chiari malformation and syringomyelia.1 Its pathogenesis and treatment are in controversy. Posterior fossa decompression has been introduced to treat the associated Chiari malformation; however, it may not be effective for symptoms with severe ventral nerve compression.2 C1-2 in situ fixation has been reported to treat minor instability in type B BI,3 yet the assessment of minor instability has not been widely accepted. We believe that the pathogenesis is chronic ventral compression of the brainstem. Transoral odontoidectomy is a classic surgical procedure to treat the pathogenesis, but it is associated with high risks of infection, velopharyngeal incompetence, and airway obstruction and often requires posterior surgery for fusion.4 Thus we use an interfacet distraction technique to move the odontoid process down and relieve ventral brainstem compression.5 Therefore interfacet structural support is necessary to maintain the distance of the interfacet. The reason for fixation is that interfacet distraction disrupts atlantoaxial stability. We designed a novel sliding-traction head holder, which can quantitatively tract and stabilize the head without support for the head or face, avoiding the risk of eyeball compression. It adapts to a variety of surgical methods and allows intraoperative changes in the patient's position. Assisted by the device, a satisfied interfacet distraction and a correction of BI were obtained. Video 1 describes how the interfacet distraction technique assisted by a sliding-traction head holder was performed in an illustrative case. The patient consented to the procedure.