[Application of three dimensional printed personalized guide plate assisted arthroscopic ankle arthrodesis in the treatment of ankle arthritis]

Objective: To compare the efficacy of conventional open ankle fusion and three dimensional(3D) printed guide plate assisted arthroscopic ankle fusion. Methods: A retrospective cohort study was performed on 256 patients with advanced traumatic ankle arthritis, who were admitted to the Department of Orthopaedics, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from May 2018 to February 2023 and underwent ankle fusion procedures. The study cohort comprised 119 males and 137 females, with an age of (59.6±9.5) years (range: 37 to 83 years). Among them, 175 cases underwent internal fixation with plates and screws (58 cases through the combined medial and lateral approach, and 117 cases through the simple lateral approach), 48 cases underwent internal fixation with screws through the anterior approach (conventional open group), and 33 cases underwent minimally invasive arthroscopic ankle fusion assisted by 3D printed guide plate (3D printed guide plate arthroscopy group). Propensity score matching was employed to achieve a 1∶1 match(caliper value=0.02) between the baseline characteristics of patients in the 3D printed guide plate arthroscopy group and the conventional open group. Perioperative and follow-up data between the two groups were compared using the t-test, Mann-Whitney U test, Wilcoxon signed rank test,χ² test, or Fisher's exact probability method, as appropriate. Results: Matching was successfully achieved with 20 cases in both the 3D printed guide plate arthroscopy group and the conventional open group, and there were no statistically significant differences in baseline characteristics between the two groups (all P>0.05). The operation time in the 3D printed guide plate arthroscopy group was significantly longer than that in the conventional open group ((88.9±5.6) minutes vs. (77.9±11.7) minutes;t=-2.392, P=0.022), while the frequency of intraoperative fluoroscopies ((1.7±0.8) times vs. (5.2±1.2) times; t=10.604, P<0.01) and length of hospitalization ((5.5±0.9) days vs. (6.4±1.5) days;t=2.480, P=0.018) were significantly lower in the 3D printed guide plate arthroscopy group compared to the conventional open group. The fusion rate was 95.0% (19/20) in the 3D printed guide plate arthroscopy group and 85.0% (17/20) in the conventional open group, with no statistically significant difference between the two groups (χ²=1.111,P=0.605). The fusion time was (12.1±2.0) weeks in the conventional open group and (11.1±1.7) weeks in the 3D printed guide plate arthroscopy group, with no statistically significant difference between the two groups (t=1.607, P=0.116). At the final follow-up, the American Orthopedic Foot and Ankle Society ankle hindfoot scale was (72.6±5.5)points in the 3D printed guide plate arthroscopy group and (70.5±5.8)points in the conventional open group, with no statistically significant difference between the two groups (t=-1.003, P=0.322). The VAS score of the 3D printed guide plate arthroscopy group was (M(IQR)) 1.50 (1.00) points, lower than that of the conventional open group by 3.00 (1.00) points, with statistically significant differences (Z=-3.937, P<0.01). The complication rate was significantly higher in the conventional open group (25.0%(5/20) vs. 5.0%(1/20), P=0.182). Conclusion: 3D printed guide plate assisted arthroscopic ankle fusion exhibited several advantages, including reduced frequency of fluoroscopies, alleviation of postoperative pain, and decreased complications and length of hospitalization.

[Clinical efficacy of transjugular intrahepatic portosystemic shunt for gastrointestinal hemorrhage in patients with idiopathic noncirrhotic portal hypertension]

Objective: To explore the medium-long term efficacy of transjugular intrahepatic portosystemic shunt (TIPS) for gastrointestinal hemorrhage in patients with idiopathic non-cirrhotic portal hypertension (INCPH). Methods: From March 2013 to July 2018, clinical data of 13 INCPH patients, including 5 males, 8 females,with gastrointestinal hemorrhage were retrospectively analyzed, who were diagnosed at the First Affiliated Hospital of Zhengzhou University, Anyang Fifth People' s Hospital and Yuncheng Central Hospital. All patients received TIPS treatment. The general information, postoperative survival rate, the incidence of rebleeding, shunt dysfunction rate, and incidence of hepatic encephalopathy were analyzed. Results: All 13 patients with INCPH completed TIPS successfully with an average age of 45±8 (33 to 59) years. The hepatic venous pressure gradient (HVPG) decreased from 20.0-26.0 (22.6±1.9) mmHg before procedure to 8.0-14.0 (9.4±3.2) mmHg after. The median follow-up time was 44±7 (31 to 53) months. One patient died of liver failure 27 months after TIPS. Hepatic encephalopathy occurred cumulatively in 1 case (1/13), 1 case (1/13) and 1 case (1/13) in 12, 24 and 36 months after TIPS. Stent restenosis occurred cumulatively in 2 cases (2/13), 3 cases (3/13) and 3 cases (3/13) in 12, 24 and 36 months after TIPS. Portal vein thrombosis occurred cumulatively in 2 cases (2/13), and no primary liver cancer developed. Conclusions: TIPS is safe and effective in the treatment of INCPH with gastrointestinal bleeding with favorable medium-long term outcome.

Midterm outcomes of penetrating keratoplasty following allogeneic cultivated limbal epithelial transplantation in patients with bilateral limbal stem cell deficiency

AIM

To evaluate the midterm outcomes of penetrating keratoplasty (PK) following allogeneic cultivated limbal epithelial transplantation (CLET) for bilateral total limbal stem cell deficiency (LSCD).

METHODS

Ten patients (10 eyes) with bilateral LSCD were enrolled in this prospective noncomparative case series study. Each participant underwent PK approximately 6mo after a CLET. Topical tacrolimus, topical and systemic steroids, and oral ciclosporin were administered postoperatively. Best-corrected visual acuity (BCVA), intraocular pressure (IOP), ocular surface grading scores (OSS), corneal graft epithelial rehabilitation, persistent epithelial defect (PED), immunological rejection, and graft survival rate were assessed.

RESULTS

The time interval between PK and allogeneic CLET was 6.90±1.29 (6-10)mo. BCVA improved from 2.46±0.32 logMAR preoperatively to 0.77±0.55 logMAR post-PK (P<0.001). Kaplan-Meier analysis of mean graft survival revealed graft survival rates of 100% at 12 and 24mo and 80.0% at 36mo. PEDs appeared in 5 eyes at different periods post-PK, and graft rejection occurred in 4 eyes. The total OSS decreased from 12.4±4.4 before allogeneic CLET to 1.4±1.51 after PK.

CONCLUSION

A sequential therapy design of PK following allogeneic CLET can maintain a stable ocular surface with improved BCVA despite the relatively high graft rejection rate.

Efficacy of rhNGF-loaded amniotic membrane transplantation for rabbit corneal epithelial and nerve regeneration

AIM

To evaluate the efficacy of recombinant human nerve growth factor-loaded amniotic membrane (rhNGF-AM) on corneal epithelial and nerve regeneration in rabbit model.

METHODS

Freshly prepared human amniotic membrane (AM) were immersed into PBS buffer containing 100 or 500 µg/mL rhNGF for 15, 30, and 60min at 4°C. The in vitro release kinetics of rhNGF was measured with ELISA. For in vivo evaluation, the AM were immersed with 500 µg/mL rhNGF for 30min. Fifty-seven rabbits were selected to establish corneal epithelial defect model. In addition to the 19 rabbits in control group, 38 rabbits received AM transplantation with or without rhNGF after the removal of central epithelium. Corneal epithelial defect area, sub-epithelial nerve fiber density, corneal sensitivity, rhNGF contents in resident AM and corneas were measured after the surgery.

RESULTS

rhNGF was sustained release from the AM within 14d in vitro, with the positive correlation with initial immersion concentration. The immersion of AM in 500 µg/mL rhNGF for 30min achieved the most stable release within 14d. After transplantation in rabbit cornea, a high concentration of rhNGF in resident rhNGF-AM and cornea was maintained within 8d. Corneal epithelial healing, nerve fiber regeneration and the recovery of corneal sensitivity were significantly accelerated after the rhNGF-AM transplantation when compared to simple AM transplantation (all P<0.05).

CONCLUSION

Simple immersion of AM achieves the sustained release of rhNGF, and promotes corneal epithelial wound healing and nerve regeneration, as well as the recovery of corneal sensitivity in rabbit.

[Research progress of diabetic corneal neuropathy]

Diabetic neuropathy is a common complication of diabetes. Its incidence among diabetic patients is more than 50%, and its ocular manifestations include diabetic retinopathy and diabetic corneal neuropathy. By using confocal microscopy, diabetic neuropathy in the cornea has been found to occur earlier than other parts of the body, which helps for early diagnosis, risk assessment and treatment options for diabetic peripheral neuropathy. The repair and treatment of nerve damage in diabetic corneal neuropathy has been frequently studied. This review focuses on the research progress of diabetic corneal neuropathy in recent years, and discusses the research findings on corneal nerve injury, anatomical and functional changes, and mechanism of injury and repair. (Chin J Ophthalmol, 2021, 57: 630-636).

[Exploration on the new situation of HIV/ADIS epidemic and the necessity of interdisciplinary concern in Tanzania]

Through the effort in nearly 40 years of Tanzania, the total number of reported cases, the prevalence of HIV/AIDS and the number of death have declined, while the number of patients receiving antiretroviral therapy has increased significantly in Tanzania. At the same time, however, there are new challenges that require more attention, such as the HIV spread to rural areas, middle and lower social classes, and female teenagers. Although the overall performance of the HIV/AIDS prevention and control response is great, there is still a need to survey the new trends of this disease at the micro-level in Tanzania. In addition, there is a necessity of interdisciplinary concern due to the prevalence of heterosexual anal sex in Tanzania.

[Establishment of Automation System for Detection of Alcohol in Blood]

OBJECTIVES

To establish an automation system for detection of alcohol content in blood.

METHODS

The determination was performed by automated workstation of extraction-headspace gas chromatography （HS-GC）. The blood collection with negative pressure, sealing time of headspace bottle and sample needle were checked and optimized in the abstraction of automation system. The automatic sampling was compared with the manual sampling.

RESULTS

The quantitative data obtained by the automated workstation of extraction-HS-GC for alcohol was stable. The relative differences of two parallel samples were less than 5%. The automated extraction was superior to the manual extraction. A good linear relationship was obtained at the alcohol concentration range of 0.1-3.0 mg/mL （r≥0.999） with good repeatability.

CONCLUSIONS

The method is simple and quick, with more standard experiment process and accurate experimental data. It eliminates the error from the experimenter and has good repeatability, which can be applied to the qualitative and quantitative detections of alcohol in blood.

Case Report Identification of a novel SLC45A2 mutation in albinism by targeted next-generation sequencing

Albinism is a diverse group of hypopigmentary disorders caused by multiple-genetic defects. The genetic diagnosis of patients affected with albinism by Sanger sequencing is often complex, expensive, and time-consuming. In this study, we performed targeted next-generation sequencing to screen for 16 genes in a patient with albinism, and identified 21 genetic variants, including 19 known single nucleotide polymorphisms, one novel missense mutation (c.1456 G>A), and one disease-causing mutation (c.478 G>C). The novel mutation was not observed in 100 controls, and was predicted to be a damaging mutation by SIFT and Polyphen. Thus, we identified a novel mutation in SLC45A2 in a Chinese family, expanding the mutational spectrum of albinism. Our results also demonstrate that targeted next-generation sequencing is an effective genetic test for albinism.

Component analyses of urinary nanocrystallites of uric acid stone formers by combination of high-resolution transmission electron microscopy, fast Fourier transformation, energy dispersive X-ray spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy

This study aimed to analyse the components of nanocrystallites in urines of patients with uric acid (UA) stones. X-ray diffraction (XRD), Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy (HRTEM), fast Fourier transformation (FFT) of HRTEM, and energy dispersive X-ray spectroscopy (EDS) were performed to analyse the components of these nanocrystallites. XRD and FFT showed that the main component of urinary nanocrystallites was UA, which contains a small amount of calcium oxalate monohydrate and phosphates. EDS showed the characteristic absorption peaks of C, O, Ca and P. The formation of UA stones was closely related to a large number of UA nanocrystallites in urine. A combination of HRTEM, FFT, EDS and XRD analyses could be performed accurately to analyse the components of urinary nanocrystallites.

Nanouric acid or nanocalcium phosphate as central nidus to induce calcium oxalate stone formation: a high-resolution transmission electron microscopy study on urinary nanocrystallites

PURPOSE

This study aimed to accurately analyze the relationship between calcium oxalate (CaOx) stone formation and the components of urinary nanocrystallites.

METHOD

High-resolution transmission electron microscopy (HRTEM), selected area electron diffraction, fast Fourier transformation of HRTEM, and energy dispersive X-ray spectroscopy were performed to analyze the components of these nanocrystallites.

RESULTS

The main components of CaOx stones are calcium oxalate monohydrate and a small amount of dehydrate, while those of urinary nanocrystallites are calcium oxalate monohydrate, uric acid, and calcium phosphate. The mechanism of formation of CaOx stones was discussed based on the components of urinary nanocrystallites.

CONCLUSION

The formation of CaOx stones is closely related both to the properties of urinary nanocrystallites and to the urinary components. The combination of HRTEM, fast Fourier transformation, selected area electron diffraction, and energy dispersive X-ray spectroscopy could be accurately performed to analyze the components of single urinary nanocrystallites. This result provides evidence for nanouric acid and/or nanocalcium phosphate crystallites as the central nidus to induce CaOx stone formation.

Coordination dynamics and coordination mechanism of a new type of anticoagulant diethyl citrate with ca(2+) ions

Diethyl citrate (Et2Cit) is a new potential anticoagulant. The coordination dynamics and coordination mechanism of Et2Cit with Ca(2+) ions and the effect of pH on the complex were examined. The result was compared with that for the conventional anticoagulant sodium citrate (Na3Cit). The reaction order (n) of Et2Cit and Na3Cit with Ca(2+) was 2.46 and 2.44, respectively. The reaction rate constant (k) was 120 and 289 L·mol(-1) ·s(-1). The reverse reaction rate constant (k re) was 0.52 and 0.15 L·mol(-1) ·s(-1), respectively. It is indicated that the coordination ability of Et2Cit with Ca(2+) was weaker than that of Na3Cit. However, the dissociation rate of the calcium complex of Et2Cit was faster than that of Na3Cit. Increased pH accelerated the dissociation rate of the complex and improved its anticoagulant effect. The Et2Cit complex with calcium was synthesized and characterized by elemental analysis, XRD, FT-IR, (1)H NMR, and ICP. These characteristics indicated that O in -COOH and C-O-C of Et2Cit was coordinated with Ca(2+) in a bidentate manner with 1 : 1 coordination proportion; that is, complex CaEt2Cit was formed. Given that CaEt2Cit released Ca(2+) more easily than Na3Cit, a calcium solution was not needed in intravenous infusions using Et2Cit as anticoagulant unlike using Na3Cit. Consequently, hypocalcemia and hypercalcemia were avoided.

Changes in urinary nanocrystallites in calcium oxalate stone formers before and after potassium citrate intake

The property changes of urinary nanocrystallites in 13 patients with calcium oxalate (CaOx) stones were studied before and after ingestion of potassium citrate (K3cit), a therapeutic drug for stones. The analytical techniques included nanoparticle size analysis, transmission electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The studied properties included the components, morphologies, zeta potentials, particle size distributions, light intensity autocorrelation curves, and polydispersity indices (PDIs) of the nanocrystallites. The main components of the urinary nanocrystallites before K3cit intake included uric acid, β-calcium phosphate, and calcium oxalate monohydrate. After K3cit intake, the quantities, species, and percentages of aggregated crystals decreased, whereas the percentages of monosodium urate and calcium oxalate dehydrate increased, and some crystallites became blunt. Moreover, the urinary pH increased from 5.96 ± 0.43 to 6.46 ± 0.50, the crystallite size decreased from 524 ± 320 nm to 354 ± 173 nm, and the zeta potential decreased from -4.85 ± 2.87 mV to -8.77 ± 3.03 mV. The autocorrelation curves became smooth, the decay time decreased from 11.4 ± 3.2 ms to 4.3 ± 1.7 ms, and the PDI decreased from 0.67 ± 0.14 to 0.53 ± 0.19. These changes helped inhibit CaOx calculus formation.