Longitudinal change of serum AIM2 levels after aneurysmal subarachnoid hemorrhage and its prognostic significance: a two-center prospective cohort study.

Absent in melanoma 2 (AIM2) is implicated in neuroinflammation. Here, we explored the prognostic significance of serum AIM2 in human aneurysmal subarachnoid hemorrhage (aSAH). We conducted a consecutive enrollment of 127 patients, 56 of whom agreed with blood-drawings not only at admission but also at days 1, 2, 3, 5, 7 and 10 days after aSAH. Serum AIM2 levels of patients and 56 healthy controls were measured. Disease severity was assessed using the modified Fisher scale (mFisher) and World Federation of Neurological Surgeons Scale (WFNS). Neurological outcome at poststroke 90 days was evaluated via the modified Rankin Scale (mRS). Univariate analysis and multivariate analysis were sequentially done to ascertain relationship between serum AIM2 levels, severity, delayed cerebral ischemia (DCI) and 90-day poor prognosis (mRS scores of 3-6). Patients, in comparison to controls, had a significant elevation of serum AIM2 levels at admission and at days 1, 2, 3, 5, 7 and 10 days after aSAH, with the highest levels at days 1, 2, 3 and 5. AIM2 levels were independently correlated with WFNS scores and mFisher scores. Significantly higher serum AIM2 levels were detected in patients with a poor prognosis than in those with a good prognosis, as well as in patients with DCI than in those without DCI. Moreover, serum AIM2 levels independently predicted a poor prognosis and DCI, and were linearly correlated with their risks. Using subgroup analysis, there were no significant interactions between serum AIM2 levels and age, gender, hypertension and so on. There were substantially high predictive abilities of serum AIM2 for poor prognosis and DCI under the receiver operating characteristic curve. The combination models of DCI and poor prognosis, in which serum AIM2, WFNS scores and mFisher scores were incorporated, showed higher discriminatory efficiencies than anyone of the preceding three variables. Moreover, the models are delineated using the nomogram, and performed well under the calibration curve and decision curve. Serum AIM2 levels, with a substantial enhancement during early phase after aSAH, are closely related to bleeding severity, poor 90-day prognosis and DCI of patients, substantializing serum AIM2 as a potential prognostic biomarker of aSAH.

Application of phosphogypsum and phosphate-solubilizing fungi to Pb remediation: From simulation to in vivo incubation.

Phosphogypsum (PG) is the produced solid waste during phosphorus (P) extraction from phosphate rocks. PG is featured by its abundant PO43- and SO42-. This study investigated the utilization of PG as a material for lead (Pb) remediation, with the assistance of functional fungus. Aspergillus niger (A. niger) is a typical phosphate-solubilizing fungi (PSF), which has high ability to secret organic acids. Oxalic acid is its major secreted organic acid, which is often applied to enhance the P release from phosphate minerals. In this study, synthetic oxalic acid increased the immobilization rate of Pb2+ up to >99 % with the addition of PG. Then, it was observed that biogenic oxalic acid from A. niger can achieve comparable remediation effects. This was due to that PG could provide sufficient P for fungal growth, which allowed sustainable remediation. Subsequently, oxalic acid secreted by A. niger significantly increased the release of active P from PG, and then induced the formation of PPb minerals. In addition, other metabolites of A. niger (such as tyrosine-like substance) can also be complexed with Pb2+. Simultaneously, A. niger did not induce evidently elevation water-soluble fluorine (F) as PG contained abundant Ca2+. Moreover, this study elucidated that oversupply of PG promoted the formation of anglesite (Ksp = 1.6 × 10-8, relatively unstable), whereas the formation of lead oxalate (Ksp = 4.8 × 10-10, relatively stable) was reduced. This study hence shed a bright light on the sustainable utilization of PG for fungus-assisted remediation of heavy metals.

Defect-induced helicity dependent terahertz emission in Dirac semimetal PtTe2 thin films.

Nonlinear transport enabled by symmetry breaking in quantum materials has aroused considerable interest in condensed matter physics and interdisciplinary electronics. However, achieving a nonlinear optical response in centrosymmetric Dirac semimetals via defect engineering has remained a challenge. Here, we observe the helicity dependent terahertz emission in Dirac semimetal PtTe2 thin films via the circular photogalvanic effect under normal incidence. This is activated by a controllable out-of-plane Te-vacancy defect gradient, which we unambiguously evidence with electron ptychography. The defect gradient lowers the symmetry, which not only induces the band spin splitting but also generates the giant Berry curvature dipole responsible for the circular photogalvanic effect. We demonstrate that the THz emission can be manipulated by the Te-vacancy defect concentration. Furthermore, the temperature evolution of the THz emission features a minimum in the THz amplitude due to carrier compensation. Our work provides a universal strategy for symmetry breaking in centrosymmetric Dirac materials for efficient nonlinear transport.

Lead remediation by geological fluorapatite combined with Penicillium Oxalicum and Red yeast.

Phosphate solubilizing fungi Penicillium oxalicum (POX) and Red yeast Rhodotorula mucilaginosa (Rho) have been applied in Pb remediation with the combination of fluorapatite (FAp), respectively. The secretion of oxalic acid by POX and the production of extracellular polymers (EPS) by Rho dominate the Pb remediation. In this study, the potential of Pb remediation by the fungal combined system (POX and Rho) with FAp was investigated. After six days of incubation, the combination of POX and Rho showed the highest Pb remove ratio (99.7%) and the lowest TCLP-Pb concentration (2.9 mg/L). The EPS combined with POX also enhanced Pb remediation, which has a 99.3% Pb removal ratio and 5.5 mg/L TCLP-Pb concentration. Meanwhile, Rho and EPS can also stimulate POX to secrete more oxalic acid, which reached 1510.1 and 1450.6 mg/L in six days, respectively. The secreted oxalic acid can promote FAp dissolution and the formation of lead oxalate and pyromorphite. Meanwhile, the EPS produced by Rho can combine with Pb to form EPS-Pb. In the combined system of POX + Rho and POX + EPS, all of the lead oxalate, pyromorphite, and EPS-Pb were observed. Our findings suggest that the combined application of POX and Rho with FAp is an effective approach for enhancing Pb remediation.

Curcumin inhibits the activity and induces apoptosis of activated hepatic stellate cell by suppressing autophagy.

Curcumin, a kind of natural compound, has been previously proven to inhibit the autophagy in hepatic stellate cells (HSCs) and induce their apoptosis. However, it is not clear whether the enhanced apoptosis of activated HSCs (aHSCs) caused by curcumin depends on autophagy inhibition. We aim to verify this hypothesis and explore the potential mechanisms in this study. Immortalized human HSC line LX-2 was used as an experimental specimen and pretreated with transforming growth factor ß1(TGF-ß1) for 24 h to activate it before drug application. The levels of autophagy, apoptosis, cell activity, lipid metabolism, and the activity of the PI3K/Akt/mTOR signal pathway were evaluated by multiple methods, such as Western blotting, mcherry-EGFP-LC3B adenoviruses transfection, immunofluorescence, Nile Red staining, flow cytometry among others. Our results showed that rapamycin, an autophagy activator, could partly offset the effects of curcumin on autophagy and apoptosis of LX-2 cells, while 3-Methyladenine (3-MA), an autophagy inhibitor, could enhance these effects. Furthermore, curcumin could promote the activity of the PI3K/Akt/mTOR signal pathway in LX-2 cells, while PI3K inhibitor could partly offset this effect and increase the autophagy level. Overall, we demonstrated that curcumin could inhibit the activity and promote LX-2 cells apoptosis by suppressing autophagy by activating the PI3K/Akt/mTOR signal pathway. In addition, lipid recovery and energy deprivation due to autophagy inhibition may be the exact mechanism by which curcumin attenuates the pro-fibrotic activity of LX-2.

[Exploration of the theory of Renying Cunkou pulse method recorded in the Yellow Emperor's Inner Canon].

Renying Cunkou pulse method is one of the classical pulse methods of acupuncture-moxibustion in the Yellow Emperor's Inner Canon, which is also a classical clinical paradigm for diagnosing and treating meridian diseases in the ancient times. Based on comprehensive review of literature and clinical practice, this paper reveals that this method compares the size of the neck Renying pulse with hand Cunkou pulse to determine the change of yin-yang and excess-deficiency identifying the affected meridians. The jing-well, xing-spring, and shu-stream points of the surface and interior meridians of affected meridians are mainly selected to regulate deficiency and excess through reinforcing and reducing methods. The Renying Cunkou pulse method possesses a simple and practical medical theory, easy diagnostic procedure, and clear meridian selection for acupuncture-moxibustion treatment, warranting further exploration of its essence and diagnostic therapeutic principles.

The Regulation of Phosphorus Release by Penicillium chrysogenum in Different Phosphate via the TCA Cycle and Mycelial Morphology.

Phosphate-solubilizing fungi (PSF) efficiently dissolve insoluble phosphates through the production of organic acids. This study investigates the mechanisms of organic acid secretion by PSF, specifically Penicillium chrysogenum, under tricalcium phosphate (Ca3(PO4)2, Ca-P) and ferric phosphate (FePO4, Fe-P) conditions. Penicillium chrysogenum exhibited higher phosphorus (P) release efficiency from Ca-P (693.6 mg/L) than from Fe-P (162.6 mg/L). However, Fe-P significantly enhanced oxalic acid (1193.7 mg/L) and citric acid (227.7 mg/L) production by Penicillium chrysogenum compared with Ca-P (905.7 and 3.5 mg/L, respectively). The presence of Fe-P upregulated the expression of genes and activity of enzymes related to the tricarboxylic acid cycle, including pyruvate dehydrogenase and citrate synthase. Additionally, Fe-P upregulated the expression of chitinase and endoglucanase genes, inducing a transformation of Penicillium chrysogenum mycelial morphology from pellet to filamentous. The filamentous morphology exhibited higher efficiency in oxalic acid secretion and P release from Fe-P and Ca-P. Compared with pellet morphology, filamentous morphology enhanced P release capacity by > 40% and > 18% in Ca-P and Fe-P, respectively. This study explored the strategies employed by PSF to improve the dissolution of different insoluble phosphates.

Lead remediation is promoted by phosphate-solubilizing fungi and apatite via the enhanced production of organic acid.

Lead (Pb) is one of the most common heavy metal pollutants in the environment, which can indirectly or directly threaten human health. Lead immobilization by apatite can reduce the effectiveness of Pb cations via the formation of pyromorphite (Pyro). However, the formation of Pyro is always depending on the release of phosphorus (P) from apatite. Phosphate-solubilizing fungi (PSF) can secrete large amounts of organic acid to promote the release of P from apatite. Although the combination of PSF and apatite has shown a huge potential in Pb remediation, this pathway needs to be more attention, especially for organic acid secretion by PSF. This research mainly reviews the possible pathway to strengthen Pb immobilization by PSF and apatite. Meanwhile, the limitation of this approach is also reviewed, with the aim of a better stabilizing effect of Pb in the environment and promoting the development of these remediation technologies.

Role of non-neuronal cholinergic system in the early stage response of epithelial-mesenchymal transformation related markers in A549 cells induced by coal particles.

Objective: This study was aimed to investigate the role of non-neuronal cholinergic system (NNCS) in the early stage response of epithelial-mesenchymal transformation (EMT) related markers in human lung adenocarcinoma A549 cells induced by coal particles. Methods: A549 cells were exposed to different concentrations of GBW11110K, GBW11126D and exogenous acetylcholinesterase (AChE) (the exposure doses were determined according to the results of CCK-8 experiment, and the doses that had no significant effects on cell viability were selected) for 24 h. After exposure, the indexes of oxidative stress (SOD and MDA), inflammatory factors (IL-6 and TNF-α), EMT marker proteins (E-cadherin and vimentin), AChE enzymatic activity and mRNA expression levels of different types of acetylcholine receptors (CHRM3, CHRM5, CHRNA5, CHRNA7, CHRNA9 and CHRNB2) were determined. Results: GBW11110K and GBW11126D exposure could lead to the following injury effects: the levels of oxidative stress and inflammatory factors changed to a certain extent (SOD decreased gradually, while MDA, IL-6 and TNF-α increased). The protein level of E-cadherin decreased while the vimentin level increased (P < 0.05), suggesting the occurrence of EMT. The AChE enzymatic activity decreased gradually. The expression of acetylcholine receptor mRNA changed as follows (GBW11110K/GBW11126D: CHRM3 (↑↑), CHRM5 (↓↓), CHRNA5 (↓↓), CHRNA7 (↓↓), CHRNA9 (- ↑), CHRNB2 (- -). The addition of exogenous AChE recombinant protein could antagonize the damage effects caused by the coal particles to a certain extent. Conclusion: The coal particle exposure could induce the change of oxidative stress response, inflammatory response and EMT related markers, down-regulate the AChE enzymatic activity, and interfere the mRNA expression levels of AChRs in A549 cells. The addition of exogenous AChE recombinant protein could reverse the above effects to a certain extent.

Complete removal of intraspinal extradural mass with unilateral biportal endoscopy.

Introduction: Unilateral biportal endoscopic (UBE) technique can easily decompress the bony spinal canal and accommodate all open surgical instruments under endoscopic guidance. However, indications and reports of this technique have been limited to degenerative and infectious diseases. Methods: We used the UBE technique for the decompression and removal of extradural mass lesions in five patients. Under endoscopic guidance, a unilateral approach was used, and decompression and flavectomy were performed. After decompression, removal of the tumor was performed using various forceps. We evaluated the technical process of the procedure, the patient's pre- and postoperative symptoms, and operative radiology and pathologic results. Results: Postoperative pain and disability improved clinically for all patients. Four patients were confirmed as having an epidural cyst and one patient was diagnosed with hemangioma. During follow-up, no recurrence was observed. Conclusions: We successfully removed five extradural mass lesions using a biportal endoscopic posterior approach without complications. The biportal endoscopic approach may have advantages, such as minimizing trauma to the normal structures, magnified endoscopic view, and early recovery after the surgery. Biportal endoscopy may be used as an alternative surgical treatment for symptomatic intraspinal extradural benign lesions.

The impacts of probiotics in eradication therapy of Helicobacter pylori.

Helicobacter pylori (H. pylori) is a well-known pathogen that infects approximately half of the world's population. It is a pathogenic agent with potential health hazards related to diverse diseases, especially digestive diseases, such as chronic gastritis, peptic ulcer, and gastric carcinoma. In clinical, antibiotics are commonly applied in eradication therapy of H. pylori. However, the increase in antibiotic resistance and side effects has induced the failure of eradication therapy. Recent studies have shown that probiotic supplementation has promising application prospects. It can restore the gastrointestinal microbiota balance and prevent dysbacteriosis caused by antibiotics. Furthermore, it has been reported to have direct or indirect inhibitory effects on H. pylori. Probiotics may have a beneficial effect on H. pylori eradication. However, the strain, dosages, duration times, and safety of probiotic supplementation need further study before clinical applications.

Imatinib inhibits pericyte-fibroblast transition and inflammation and promotes axon regeneration by blocking the PDGF-BB/PDGFRß pathway in spinal cord injury.

BACKGROUND: Fibrotic scar formation and inflammation are characteristic pathologies of spinal cord injury (SCI) in the injured core, which has been widely regarded as the main barrier to axonal regeneration resulting in permanent functional recovery failure. Pericytes were shown to be the main source of fibroblasts that form fibrotic scar. However, the mechanism of pericyte-fibroblast transition after SCI remains elusive. METHODS: Fibrotic scarring and microvessels were assessed using immunofluorescence staining after establishing a crush SCI model. To study the process of pericyte-fibroblast transition, we analyzed pericyte marker and fibroblast marker expression using immunofluorescence. The distribution and cellular origin of platelet-derived growth factor (PDGF)-BB were examined with immunofluorescence. Pericyte-fibroblast transition was detected with immunohistochemistry and Western blot assays after PDGF-BB knockdown and blocking PDGF-BB/PDGFRß signaling in vitro. Intrathecal injection of imatinib was used to selectively inhibit PDGF-BB/PDGFRß signaling. The Basso mouse scale score and footprint analysis were performed to assess functional recovery. Subsequently, axonal regeneration, fibrotic scarring, fibroblast population, proliferation and apoptosis of PDGFRß+ cells, microvessel leakage, and the inflammatory response were assessed with immunofluorescence. RESULTS: PDGFRß+ pericytes detached from the blood vessel wall and transitioned into fibroblasts to form fibrotic scar after SCI. PDGF-BB was mainly distributed in the periphery of the injured core, and microvascular endothelial cells were one of the sources of PDGF-BB in the acute phase. Microvascular endothelial cells induced pericyte-fibroblast transition through the PDGF-BB/PDGFRß signaling pathway in vitro. Pharmacologically blocking the PDGF-BB/PDGFRß pathway promoted motor function recovery and axonal regeneration and inhibited fibrotic scar formation. After fibrotic scar formation, blocking the PDGFRß receptor inhibited proliferation and promoted apoptosis of PDGFRß+ cells. Imatinib did not alter pericyte coverage on microvessels, while microvessel leakage and inflammation were significantly decreased after imatinib treatment. CONCLUSIONS: We reveal that the crosstalk between microvascular endothelial cells and pericytes promotes pericyte-fibroblast transition through the PDGF-BB/PDGFRß signaling pathway. Our finding suggests that blocking the PDGF-BB/PDGFRß signaling pathway with imatinib contributes to functional recovery, fibrotic scarring, and inflammatory attenuation after SCI and provides a potential target for the treatment of SCI.

Aspergillus niger Enhances Organic and Inorganic Phosphorus Release from Wheat Straw by Secretion of Degrading Enzymes and Oxalic Acid.

To explore the mechanisms of crop straw degradation and phosphorus (P) release by phosphate-solubilizing fungi (PSF), a typical PSF Aspergillus niger (A. niger, ANG) was investigated for the degradation of wheat straw (WST) in this work. The results revealed that A. niger significantly increased wheat straw degradation (30%) compared with no A. niger treatment (7.7%). Meanwhile, more than 92% of total P was released from WST by A. niger, much higher than from WST treatment (69.5%). Although the ratios of inorganic P release between WST and WST + ANG treatments were similar (17.6 vs 19.7%), a significant difference occurred between their release of organic P, i.e., WST (51.9%) vs WST + ANG (72.5%). The high enzyme activity of ß-1,4-glucanase and ß-glucosidase produced by A. niger contributed to the wheat straw degradation and organic P release compared with no A. niger treatment. Oxalic acid secreted by A. niger dominated the release of inorganic P from WST. Our findings suggested that A. niger is an efficient microbial agent for crop straw degradation and P release, which could be a candidate in the pathway of straw return.

Phosphorus biogeochemistry regulated by carbonates in soil.

Phosphates are the dominant phosphorus (P) source on Earth. The phosphates govern available P in soil, or even the complete ecosystem. The common deficiency of available P in carbonate-enriched soils suggests the tight correlation between P and C biogeochemistry, although the two elements have diverse abundance in soil. The influences of carbonates on P cycle were reviewed in this study, via both abiotic and biotic pathways. The abiotic processes at geochemical scale include element release, transport, sorption, desorption, weathering, precipitation, etc. The sorption of P on carbonate and buffering ability of carbonates were particularly addressed. Biotic factors are ascribed to various microorganisms in soil. As the most active P pool in soil, microorganisms prefer to consume abundant P, and then accumulate it in their biomass. Carbonates, however, are usually utilized by microorganisms after conversion to organic C. Meanwhile, extracellular precipitation of Ca-P phases significantly regulates the transportation of P in/out the cells. Moreover, they boost and complexify both carbonates and P turnover in soil via bioweathering and biomineralization, i.e., the intense interactions between biosphere and lithosphere. Based on this review, we proposed that carbonates may negatively affect P supply in soil system. This comprehensive review regarding the regulation by carbonates on P biogeochemistry would shed a light on predicting long-term P availability influenced by C biogeochemistry.

Primitive neuroectodermal tumor of the prostate in a 58-year-old man: A case report.

BACKGROUND: Primitive neuroectodermal tumor (PNET), especially located in the prostate, is a rare tumor that mainly occurs in young men. Bladder or rectum invasion and distant metastasis are strongly associated with a poor prognosis. Combination therapy, including radical surgery, adjuvant chemotherapy, and radiotherapy, is available. We present a case of prostatic PNET and a review of 17 cases identified in the literature. CASE SUMMARY: A 58-year-old man was admitted complaining of dysuria for 2 years. Computed tomography and magnetic resonance imaging showed a large cystic-solid mass in the pelvic cavity compressing the surrounding bladder and rectum. The mass was iso- to hyperintense on T1-weighted imaging (WI) and heterogeneously hyperintense on T2WI. Cystic degeneration and necrosis were seen in the tumor, and solid tissues within the mass enhanced on contrast-enhanced scan. The patient underwent robot-assisted laparoscopic pelvic tumor resection. Histologically, the presence of many small round cells that were positive for expression of CD99, vimentin, and synaptophysin established the diagnosis of PNET in the prostate after surgery. The patient underwent adjuvant chemotherapy. During 34 mo of follow-up, the patient had no signs or symptoms of recurrence or residual disease. CONCLUSION: We present the case of the oldest prostatic PNET patient, who has a good prognosis. This illustrates how older men with prostatic PNET may also benefit from the combination therapy, like younger adults, and achieve a long-term survival. As always, PNET should be considered in the differential diagnosis of aggressive prostatic tumors in young men.

Long-term drought aggravates instability of alpine grassland productivity to extreme climatic event.

The frequency and severity of extreme weather events are increasing and expected to increase more in the future, together with global change. However, how extreme events and global change factors interactively influence community structures and ecosystem processes is largely unknown. Here, we investigated the responses of the temporal stability and resilience of aboveground net primary productivity (ANPP) of an alpine meadow to an extreme flooding event under different treatments of experimental drought and clipping. We found that ecosystems that were exposed to drought treatments for 3 years significantly decreased the temporal stability of community productivity but increased resilience to flooding, whereas their resistance to or recovery from flooding did not change. Neither clipping nor its interaction with drought altered the responses of these community stability metrics to flooding. Drought treatments significantly decreased plant species richness and asynchrony and dominant species stability, leading to a decrease in temporal stability and an increase in resilience in response to the extreme flooding event. The study also revealed that the change in species asynchrony was the dominant impact pathway determining the responses of resilience and temporal stability to flooding. Our results highlight that alpine grassland that experiences a multiyear drought may aggravate the instability of community productivity to extreme climatic events by reducing species asynchrony.

Evaluating the survival of Aspergillus niger in a highly polluted red soil with addition of Phosphogypsum and bioorganic fertilizer.

Phosphate-solubilizing fungi (PSF) can enhance P release from phosphate minerals to immobilize heavy metals. However, this promotion substantially depends on their survival in highly polluted soils. The aim of this study was to investigate the survival of PSF after addition of phosphogypsum (PG) and bioorganic fertilizer (BF) in the soil with coexistence of multiple heavy metals, e.g., Pb, As, Cd, Sb, etc. Addition of typical PSF (Aspergillus niger) did not promote the formation of pyromorphite (the most stable form of Pb), possibly due to the buffering effect of the soil (the secreted oxalic acid was neutralized) and limited P supply. Meanwhile, despite that A. niger has high tolerance to heavy metal stress, its survival was significantly declined due to the deficiency of available P. It was also shown that PG, as the major by-product in phoschemical industry, still has relatively high available P compared with common natural soils. PG addition dramatically increased available P (up to 93.87 mg/kg) and the subsequent fungal growth. However, sole PG did not promote the formation of pyromorphite, probably as the abundant Fe2+ and Mn2+ prevented the contact between PO43- and Pb2+ in the soil system. The enhanced soil respiration after addition of BF and PG confirmed the promoted microbial activity (elevated to 3465.58 µg C kg h-1). This study showed PG's potential as P source for both microbial growth and heavy metal remediation in soil system. A combination of PG, A. niger, and BF can hence achieve long-term bioremediation of heavy metals.

The Learning Curve of Unilateral Biportal Endoscopic (UBE) Spinal Surgery by CUSUM Analysis.

Objective: To assess the learning curve of the unilateral biportal endoscopic (UBE) technique for the treatment of single-level lumbar disc herniation by cumulative summation (CUSUM) method analysis. Methods: A retrospective analysis was conducted to assess 97 patients' general condition, operation time, complications, and curative effect of single segmental UBE surgery performed by a spinal surgeon in his early stage of this technique. The learning curve of operation time was studied using a CUSUM method, and the cut-off point of the learning curve was obtained. Results: The operation time was 30 - 241(97.9 ± 34.7) min. The visual analog scale score of lower limb pain decreased from 5.75 ± 0.81 before the operation to 0.39 ± 0.28 at the last follow-up (P < 0.05). The Oswestry disability index score decreased from 66.48 ± 4.43 before the operation to 14.57 ± 3.99 at the last follow-up (P < 0.05). The CUSUM assessment of operation time revealed the learning curve was the highest in 24 cases. In the learning stage (1-24 cases), the operation time was 120.3 ± 43.8 min. In the skilled stage (25-97 cases), the operation time was 90.5 ± 27.8 min. Conclusions: About 24 cases of single segmental UBE operation are needed to master the UBE technique.