[In vitro activity of ß-lactamase inhibitors avibanvctam and relebactam in combination with ß-lactams against multidrug-resistant Mycobacterium tuberculosis and mutations of resistance genes].

Objective: To evaluate the activity of six ß-lactams in combination with three ß-lactamase inhibitors against mycobacterium tuberculosis(MTB) in vitro. Methods: A total of 105 multidrug-resistant tuberculosis (MDR-TB) strains from different regions of Henan province from January to September 2020 were included in this study. Drug activity of six ß-lactams (biapenem, meropenem, imipenem, doripenem, ertapenem and tebipenem) alone or in combination with ß-lactamase inhibitors (clavulanic acid, avibactam and relebactam) was examined by minimum inhibitory concentration method (MICs) against 105 clinical isolates. Mutations of blaC, ldtmt1 and ldtmt2 were analyzed by PCR and DNA sequencing. Chi-square test was used to compare the antimicrobial activities of different ß-lactam drugs. Results: Out of the ß-lactams used herein, tebipenem was the most effective against MDR-TB and had an MIC50 value of 8 mg/L(χ2=123.70,P=0.001). Besides, after the addition of ß-lactamase inhibitors, the MICs of most ß-lactam drugs were reduced more evidently in the presence of avibactam and relebactam compared to clavulanic acid.Especially, relebactam decreased both the MIC50 and MIC90 of telbipenem by 16-fold, and diluted the MIC of 23 (21.90%) and 41 (39.04%) isolatesby 32-fold and 16-fold.In addition, a total of 13.33% (14/105) of isolates harbored mutations in the blaC gene, with three different nucleotide substitutions: AGT333AGG, AAC638ACC and ATC786ATT. For the strains with Ser111Arg and Asn213Thr substitution in BlaC, the MIC values of the meropenem-clavulanate combination were reduced compared with a synonymous single nucleotide polymorphism (SNP) group. Conclusions: Both avibactam and relebactam had better synergistic effects on ß-lactams than clavulanic acid. The combination of tebipenem and relebactam showed the most potent activity against MDR-TB isolates. In addition, the Ser111Arg and Asn213Thr substitution of BlaC may be associated with an increased susceptibility of MDR-TB isolates to meropenem in the presence of clavulanate.

[Management of the nondisplaced type Herbert D1 scaphoid fracture with robot navigation combined with wrist arthroscopy].

To investigate the feasibility and the clinical efficiency of robot navigation combined with wrist arthroscopy in minimally invasive treatment of nondisplaced type Herbert D1 scaphoid fracture. A retrospective analysis was performed on 9 patients who underwent nondisplaced type Herbert D1 scaphoid fracture in Xuzhou Renci Hospital from December 2019 to January 2021. Before the operation and at the last follow-up, grip strength, pinching force, modified wrist Mayo score and visual analogue scale (VAS) of wrist pain were recorded and compared. The average follow-up time was 14.1 months (7.5-24.0 months). All the fractures achieved primary healing after an average of 13.3 weeks (10-18 weeks). The average flexion and dorsal extension activity of the injured wrist was 51.2°±9.4°, 68.0°±7.3°, and the radial and ulnar deviation was 19.3°±6.2°, 45.7°±7.8°, respectively. At the final follow-up, there were statistically significant differences in grip strength, pinch strength, wrist Mayo score and VAS when compared with those before the operation (all P<0.05). The results demonstrated that robot navigation combined with wrist arthroscopy for nondisplaced type Herbert D1 scaphoid fracture is effective and minimally invasive with a short recovery time and satisfactory healing rate.

[A prospective randomized controlled clinical study on the treatment of hypertrophic scar after burn by fractional carbon dioxide laser combined with autologous fat injection].

Objective: To explore the clinical effects of fractional carbon dioxide laser combined with autologous fat injection in the treatment of hypertrophic scar after burn. Methods: From April 2018 to April 2019, 12 patients with hypertrophic scar after burn who met the inclusion criteria were admitted to the Department of Plastic Surgery and Burns of Xuzhou Renci Hospital, and were included in this prospective randomized controlled clinical study. There were 7 males and 5 females with age of (32±11) years and scar area of (612±195) cm(2). One scar was selected from each patient and divided into two equal area scars, and they were divided into combined treatment group and laser alone group with 12 scars in each group according to the random number table. The scar in laser alone group was only treated with fractional carbon dioxide laser, while the scar in combined treatment group was injected with autologous granular fat and then treated with fractional carbon dioxide laser. Scars in the two groups were treated once every 2 months, totally 3 times. Before the first treatment and 6 months after the last treatment, the scars in the two groups were evaluated by modified Vancouver Scar Scale (mVSS), hematoxylin-eosin staining and color Doppler ultrasound. Six months after the last treatment, the curative effect of scars in the two groups was evaluated, and the effective number of scar treatment was calculated. The adverse reactions during the whole treatment were recorded. Data were statistically analyzed with independent sample t test, paired sample t test, and McNemar exact probability method test. Results: Six months after the last treatment, the mVSS score of scars in combined treatment group was (4.5±0.4) points, which was significantly lower than (7.8±0.6) points in laser alone group (t=10.000, P<0.01). Six months after the last treatment, the mVSS scores of scars in combined treatment group and laser alone group were significantly lower than those before the first treatment ((13.5±0.7) and (13.8±0.6) points, t=8.805, 9.010, P<0.01). The effective number of scar treatment in combined treatment group was significantly more than that in laser alone group (P<0.05). There was no scar aggravation, infection, or other adverse reactions during the treatment of scars in both groups. Before the first treatment, the scars in both groups had large collagen, disordered arrangement, proliferation of capillaries, infiltration of some inflammatory cells, and disappearance of skin appendages. Six months after the last treatment, the scar collagen in both groups was sparse and orderly arranged, and the vascular density was reduced. The improvement of scars in combined treatment group was more obvious than that of laser alone group. Six months after the last treatment, the scar thickness in combined treatment group was significantly smaller than that in laser alone group (t=2.657, P<0.05). Before the first treatment, the blood flow of scars in both groups was abundant; 6 months after the last treatment, the blood flow of scars in combined treatment group was significantly less than that in laser alone group. Conclusions: Fractional carbon dioxide laser combined with autologous fat injection in the treatment of hypertrophic scar after burn can significantly reduce the pain and itching symptoms of scar, and improve the thickness, texture, and congestion of scar. The combined treatment has synergistic effect and less adverse reactions, providing a more effective treatment for patients with hypertrophic scar.

[Effects of medial upper arm bilobed free flaps in the repair of two skin and soft tissue defects of hand].

Objective: To summarize the effects of medial upper arm bilobed free flaps in the repair of two skin and soft tissue defects of hand. Methods: From May 2014 to May 2016, 7 patients of two skin and soft tissue defects of hand with exposures of phalanges and tendons were treated in Xuzhou Renci Hospital, including 5 males and 2 females, aged from 19 to 41 years. Each defect area ranged from 3.0 cm×1.5 cm to 6.0 cm×3.0 cm. The medial upper arm bilobed free flaps were used to repair the defects, and the area of each lobe of the flaps ranged from 4.0 cm×2.0 cm to 8.0 cm×3.5 cm. The donor sites were sutured directly. The survival of the flaps was recorded. During follow-up, the recovery of donor and recipient sites was observed, the two-point discrimination distance of the flaps was measured, and the hand function was assessed by the trial criteria of the upper limb functional assessment of the Hand Surgery Society of the Chinese Medical Association. Results: All flaps survived smoothly, and the wounds and donor site incisions were healed. All patients were followed up, and the follow-up time lasted for 6 to 15 months. The color and texture of the flaps were similar to the surrounding normal skin, and the shape of the flaps was good. There was no obvious scar in the donor site, and the elbow joint function was normal. One patient developed ulnar numbness one month after operation and relieved after 3 months of treatment with neurotrophic drugs and local physiotherapy, etc. Six months after operation, the two-point discrimination distance of the flaps was 5.5-8.0 mm, and the hand function evaluation was excellent in 3 cases, good in 3 cases, and middle in 1 case. Conclusions: The medial upper arm bilobed free flap has both good texture and good appearance, and the scar of donor site is concealed. It is a good method to repair two skin and soft tissue defects of hand.

[Comparison of the efficacies of cross priming amplification and RealAmp with XpertMTB/RIF for the diagnosis of pulmonary tuberculosis at peripheral microscopic center].

Objective: To compare the efficacies of cross priming amplification (CPA) and RealAmp with XpertMTB/RIF for the diagnosis of pulmonary tuberculosis(TB) at peripheral microscopic centers. Methods: From December of 2014 to December of 2015, 3 193 patients suspected with TB were enrolled consecutively at 3 county level TB clinical clinics in Zhongmu, Xinmi and Dengzhou of Henan province. Totally 3 193 collected sputum samples were detected by smear microscopy, L-J media culture, CPA, RealAmp and Xpert MTB/RIF. The culture positive samples were tested by MPB64 for strain identification. The sensitivity and specificity of CPA, RealAmp and Xpert MTB/RIF were calculated according to L-J solid culture results and clinical diagnosis results. Results: The sensitivity of CPA, RealAmp and Xpert MTB/RIF were 85.5%(413/483), 85.5%(413/483) and 87.9%(422/480), respectively, compared with L-J solid culture, the difference among the 3 methods being not significant(χ(2)=1.6, P>0.05). The specificity of CPA, RealAmp and Xpert MTB/RIF were 96.8%(2 624/2 170), 93.2%(2 527/2 170) and 95.3%(2 567/2 170) compared with culture; and there was a significantly statistic difference among the 3 methods(χ(2)=37.8, P<0.001). The sensitivity of smear microscopy, culture, CPA, RealAmp and Xpert MTB/RIF was 21.7%(300/1 383), 34.9%(483/1 383), 34.6%(478/1 383), 39.2%(542/1 383) and 38.1%(526/1 381) compared with clinical diagnosis. The sensitivity of CPA, RealAmp and Xpert MTB/RIF was higher than that of smear (χ(2) =31.9, P<0.01), but there was no significantly statistic difference between the 3 molecular methods(χ(2)=2.9, P>0.05). The specificity of smear microscopy, L-J solid culture, CPA, RealAmp and Xpert MTB/RIF was 100%(1 810/1 810), 100%(1 810/1 810), 98.8%(1 789/1 810), 98.8%(1 756/1 810) and 97.0%(1 788/1 810), and there was no significantly statistic difference among the 3 molecular methods(χ(2)=0.16, P>0.05). Conclusion: The capability of CPA and RealAmp for diagnosing pulmonary TB was similar to Xpert MTB/RIF.The former 2 methods were more suitable to apply to the diagnoses of pulmonary TB in peripheral laboratories.

Post-targeting strategy for ready-to-use targeted nanodelivery post cargo loading.

Based on boronate formation, this study reports a post-targeting methodology capable of readily installing versatile targeting modules onto a cargo-loaded nanoplatform in aqueous mediums. This permits the targeted nanodelivery of broad-spectrum therapeutics (drug/gene) in a ready-to-use manner while overcoming the PEGylation-dilemma that frequently occurs in conventional targeting approaches.

Improved efficiency Si-photonic attenuator.

A forward-biased p-i-n diode integrated with a ridge waveguide forms a basic Si attenuator building block. Disruptive power improvement was achieved through a recessed contact configuration by limiting the amount of Si volume for carrier recombination. A device model was established by using realistic surface recombination velocities instead of effective carrier lifetime concept to understand the device physics of the afore-mentioned Si attenuator.

Aggregation kinetics and stability of structures formed by magnetic microspheres.

Stable rings formed by magnetization-controllable microspheres at zero field are observed and reported in this Rapid Communication. The magnetic microspheres were made by plating glass beads with a critical thickness of Ni film. We found that the ring leading to magnetic flux closure is the most stable configuration. At high concentrations, all individual rings, chains, and clusters join together to form a netlike structure. A computer simulation based on the dipole-dipole interaction, without thermal noise, has been carried out, and the results are in good agreement with the experimental observations. Based on an analytic approach we give a simple explanation of the formation and stability of rings.

[Alveolar hydatid disease: report of 90 cases].

From 1960 through 1992, 2750 cases of hydatid disease disease were admitted to our hospital, among them there were 90 cases of alveolar hydatid disease proved by laparotomy, biopsy, or autopsy. The preoperative misdiagnosis rate in this series was 24.3% owing mainly to the difficulty of differentiating from multilocular echinococcosis and liver cancer. Basing on clinical and pathological features, the authors proposed its diagnostic and staging principles, and therapeutic approaches to improve the prognosis of this disease.