Super-pulse thulium fiber laser (hereinafter referred to as thulium laser) has shown broad application prospects in medical research, especially in the treatment of urinary tract stones.Thulium laser has a thin fiber diameter, which reduces the occupation of the working channel and increases the irrigation water flow.Currently, the peak power reaches up to 500 W, the single pulse energy to 6 J, and the frequency to 2000 Hz.The stone-breaking mechanism of thulium laser is photothermal and photomechanical.Different combinations of energy and frequency will significantly affect the volume of stone fragments. "High energy and low frequency" is more suitable for "fragmentation" stone breaking, while "low energy and high frequency" is more suitable for "powderization" stone breaking.Some in vitro experiments have confirmed that thulium laser has higher stone-breaking efficiency, less stone displacement, and more obvious thermal effects compared to holmium laser.Clinically, thulium laser has been applied to ureteroscopic lithotripsy and percutaneous nephrolithotomy., and the stone free rate and safety are relatively high.This article reviews the stone-breaking principles, in vitro experiments, and clinical applications of thulium laser, aiming to provide better theoretical support and practical experience for the development and application of super-pulse thulium fiber laser in the future.

Chest tightness variant asthma(CTVA)is an atypical form of asthma with chest tightness as the sole or predominant symptom.The underlying receptors for chest tightness are bronchial C-fibers or rapidly adapting receptors.The nerve impulses are transmitted via the vagus nerve and processed in different regions of the cerebral cortex.Chest tightness is associated with sensory perception,and CTVA patients may have heightened ability to detect subtle changes in lung function,but such sensory perception is unrelated to respiratory muscle activity,lung hyperinflation,or mechanical loading of the respiratory system.Airway inflammation,pulmonary ventilation dysfunction(especially involving small airways),and airway hyperresponsiveness may underlie the sensation of chest tightness.CTVA patients are prone to comorbid anxiety and depression,which share similar central nervous system processing pathways with dyspnea,suggesting a possible neurological basis for the development of CTVA.This article examines the recognition and mechanisms of chest tightness,and explores the pathogenesis of CTVA,focusing on its association with airway inflammation,ventilation dysfunction,airway hyperresponsiveness,and psychosocial factors.

Percutaneous nephrolithotomy(PCNL) has always been the first-line minimally invasive treatment for staghorn kidney stones, with high surgical efficiency and first-stage stone free rate. However, due to the complexity of stones and the difficulty of surgery, serious complications such as postoperative bleeding, infection, and renal function damage often occur. Needle-perc assisted endoscopic surgery(NAES) surgery, also known as needle-perc assisted endoscopic surgery, is an innovative model based on needle-perc proposed by our center. The S+ N mode is standard tract PCNL combined with needle-perc, which not only improves the efficiency and stone free rate, but also reduces the number of tracts, effectively protecting renal function and reducing complications. This article reports a case of complete staghorn kidney stones that were completely removed by NAES surgery in one stage, with no complications after surgery and the patient recovering quickly and being discharged from the hospital.

Objective:To analyze the safety and efficacy of ultrasound-guided needle-perc assisted retrograde intrarenal surgery (RIRS) in the treatment of small but complex renal calculi, and summarize our clinical experience.Methods:The clinical data of 36 patients with small but complicated renal stones treated by ultrasound-guided needle-perc assisted RIRS in Beijing Tsinghua Changgung Hospital from January 2020 to April 2022, were retrospectively analyzed. There were 25 males and 11 females. The average age was (54.7±6.1) years, and the body mass index (BMI) was (26.3±3.1) kg/m 2. The maximum diameter of the calculi was (1.8±0.7) cm. There were 28 patients without renal hydronephrosis before operation, 8 patients with mild to moderate renal hydronephrosis, 4 patients with caliceal diverticular stones, 32 patients with lower pole stones, 10 patients with ureteral stones, 6 patients with previous surgical history of ipsilateral kidney stones, and 3 patients with stones in the solitary kidneys. Patients were placed in oblique supine lithotomy position or prone split leg position (female). For lower pole stones or diverticular stones that were difficult to be handled by flexible ureteroscope, the needle-perc was used to puncture the stones in target calyx under ultrasound guidance. Holmium laser was then used to pulverize or fragment the calculi, and the flexible ureteroscope was used to remove or further pulverize the stone fragments. Perioperative indexes and postoperative complications were recorded, and stone-free rate was analyzed. Results:All 36 cases were successfully operated. The median operation time was 61.5(59.0, 66.8)min, with a median decrease in hemoglobin on the first postoperative day of 1.6(0.8, 2.0)g/ L, a median postoperative hospital stay of 1.5(1.0, 2.0)days, and a median needle-perc tract of 1(1, 2). The complications were recorded in 4 patients (11.1%), all of which were Clavien-Dindo grade I, including postoperative fever in 2 patients and analgesic use in 2 patients. The primary stone-free rate was 83.3% (30/36). The 6 patients with residual stones were treated by external physical vibration lithecbole on the 3rd to 7th day after surgery. After 1 month follow-up, residual stone expulsion were seen in 3 patients. Three patients with residual stones were followed up regularly. The final stone-free rate was 91.7% (33/36).Conclusions:Ultrasound-guided needle-per assisted RIRS is safe and effective in the treatment of small but complex renal calculi, with high postoperative stone free rate and low complication rate.

【Objective】 The thermal effects of super-pulsed thulium fiber laser (TFL) at different powers,lithotripsy modes and irrigation rates were studied using a 3D kidney model to simulate ureteral lithotripsy in vivo. 【Methods】 A thermal effect model was established in vitro. Under the same conditions of laboratory temperature and equipment,the temperature around the optical fiber was measured and compared when different optical fiber diameters,powers,lithotripsy modes and irrigation rates were used to simulate lithotripsy by TFL. 【Results】 There was significant difference in the temperature around the optical fiber caused by two fibers with different diameters under the same conditions (P<0.05). Under the same conditions,different lithotripsic modes produced different temperatures,and the temperature of "high energy and low frequency" was lower than that of "low energy and high frequency" (P<0.05). When the power was 10 W and the minimum irrigation rate was 10 mL/min,the plateau temperature did not reach the safety threshold (43 ℃). When the power was 20 W and the minimum irrigation rate was 10 mL/min,the platform temperature exceeded the safety threshold. When the irrigation rate was 20 mL/min,the platform temperature did not reach the safety threshold. 【Conclusion】 In the study of ureteral lithotripsy in vitro,the power,mode,irrigation rate and optical fiber diameter are factors affecting the thermal effects of TFL. No matter what kind of lithotripsy mode and fiber diameter,the temperature around the fiber is safe when the lithotripsy power is ≤10 W and the irrigation rate is ≥10 mL/min;when the lithotripsy power is ≤20 W and the irrigation rate is ≥20 mL/min,the temperature around the fiber is safe.

Objective:To evaluate the performance of machine learning (ML) based on automated breast volume scanner (ABVS) radiomics in distinguishing benign and malignant BI-RADS 4 lesions.Methods:Between May to December 2020, patients with BI-RADS 4 lesions from the Affiliated Hospital of Southwest Medical University (Center 1) and Guangdong Provincial Hospital of Traditional Chinese Medicine (Center 2) were prospectively collected and divided into training cohort (Center 1) and external validation cohort (Center 2). The radiomics features of BI-RADS 4 lesions were extracted from the axial, sagittal and coronal ABVS images by MaZda software. In the training cohort, 7 feature selection methods and thirteen ML algorithms were combined in pairs to construct different ML models, and the 6 models with the best performance were verified in the external validation cohort to determine the final ML model. Finally, the diagnostic performance and confidence (5-point scale) of radiologists (R1, R2 and R3, with 3, 6 and 10 years of experience, respectively) with or without the model were evaluated.Results:①A total of 251 BI-RADS 4 lesions were enrolled, including 178 lesions (91 benign, 87 malignant) in the training cohort and 73 lesions (44 benign, 29 malignant) in the external validation cases. ②In the training cohort, the 6 ML models (DNN-RFE, AdaBoost-RFE, LR-RFE, LDA-RFE, Bagging-RFE and SVM-RFE) had the best diagnostic performance, and their AUCs were 0.972, 0.969, 0.968, 0.968, 0.967 and 0.962, respectively. ③In the external validation cohort, the DNN-RFE still had the best performance with the AUC, accuracy, sensitivity, specificity, PPV and NPV were 0.886, 0.836, 0.934, 0.776, 86.8% and 82.5%, respectively. ④Before model assistance, R1 had the worst diagnostic performance with the accuracy, sensitivity, specificity, PPV and NPV were 0.680, 0.750, 0.640, 57% and 81%, respectively. After model assistance, the diagnostic performance of R1 was significantly improved ( P=0.039), and its diagnostic sensitivity, specificity, accuracy, PPV and NPV improved to 0.730, 0.810, 0.930, 68% and 94%; while the improvement of R2 and R3 were not significantly ( P=0.811, 0.752). Meanwhile, the overall diagnostic confidence of the 3 radiologists increased from 2.8 to 3.3 ( P<0.001). Conclusions:The performance of ML based on ABVS radiomics in distinguishing between benign and malignant BI-RADS 4 lesions is good, which may improve the diagnostic performance of inexperienced radiologists and enhance diagnostic confidence.

Objective:To study the risk factors of intra-abdominal infection after hepatectomy in patients with primary liver neoplasms.Methods:The clinical data of patients with primary liver neoplasms who underwent hepatectomy at the Department of Hepatobiliary Surgery, Mengchao Hepatobiliary Hospital of Fujian Medical University from January 2019 to December 2021 were retrospectively analyzed. Of 1 229 patients who were enrolled, 48 patients developed postoperative abdominal infection. There were 45 males and 3 females, with age of 58.0 (45.0, 66.0) years old in the infected group. Forth-eight patients without postoperative abdominal infection were selected based on the random number formula to be allocated to the uninfected group to include 44 males and 4 females with age of 58.5 (48.5, 64.8) years old. The general data, preoperative and postoperative laboratory test results, types of liver neoplasms and hepatectomy, pathogenic infective microorganisms and their drug sensitivity tests were collected. Univariate analysis was used to analyze the related factors of intra-abdominal infection after hepatectomy, and significant factors were included in logistic multivariate regression analysis.Results:Of 24 pathogenic strains which were detected in the 143 samples of abdominal infection, the positive rate of culture was 16.78%(24/143). Multivariate logistic regression analysis showed that prealbumin <180 mg/L ( OR=3.757, 95% CI: 1.117-12.634), intraoperative blood transfusion ( OR=6.363, 95% CI: 1.301-31.113) and the time of drainage tube placement ≥7 d ( OR=31.098, 95% CI: 6.906~140.029) were independent risk factors of intra-abdominal infection after hepatectomy. Conclusion:Prealbumin <180 mg/L, intraoperative blood transfusion and the time of drainage tube placement ≥7 d were independent risk factors of intra-abdominal infection after hepatectomy for primary liver neoplasms.

Acute cellular rejection (ACR) is a common complication after lung transplantation, which is mainly caused by the immune response of T lymphocytes recognizing the major histocompatibility complex on the cellular surface of grafts. It is currently considered as the main pattern of acute rejection. ACR is not only a direct cause of death of recipients, but also a high-risk factor for chronic rejection after lung transplantation. Nevertheless, it is a challenging task to deliver the diagnosis and treatment of ACR following lung transplantation. In this article, new progresses on the risk factors, pathogenesis, diagnosis and treatment of ACR in lung transplant recipients were summarized, aiming to improve the diagnostic and treatment efficiency of ACR and prolong the survival of recipients.

Objective To analyze the risk factors and clinical prognosis of acute kidney injury (AKI) early after lung transplantation. Methods Clinical data of 155 recipients undergoing lung transplantation or combined heart-lung transplantation were retrospectively analyzed, and they were divided into the AKI group (n=104) and non-AKI group (n=51) according to the 2012 Kidney Disease: Improving Global Outcomes Clinical Practice Guideline. The incidence of AKI early after lung transplantation was summarized. The main indexes of recipients were collected. The risk factors of the occurrence of AKI early after lung transplantation were subjected to univariate and multivariate analysis. The clinical prognosis of lung transplant recipients was evaluated and the survival curve was delineated. Results The incidence of AKI early after lung transplantation was 67.1%(104/155), including 47 recipients with stage 1 AKI, 34 recipients with stage2 AKI and 23 recipients with stage 3 AKI, respectively. Sixteen recipients required continuous renal replacement therapy (CRRT) early after lung transplantation. Preoperative complication with diabetes mellitus, preoperative complication with pulmonary hypertension, intraoperative mean arterial pressure (MAP) < 60 mmHg, intraoperative massive blood transfusion, and treatment with excessive therapeutic concentration of tacrolimus (Tac) within postoperative 1 week were the independent risk factors for the occurrence of AKI early after lung transplantation. Up to the end of follow-up, 66 recipients (42.6%) died, including 50 recipients in the AKI group and 16 recipients in the non-AKI group. The cumulative survival rate in the AKI group was significantly lower than that in the non-AKI group (40% vs. 66%, P < 0.05). With the increase of AKI severity, the cumulative survival rate of lung transplant recipients was decreased. Conclusions AKI develops early after lung transplantation with high incidence and poor clinical prognosis. Preoperative complication with diabetes mellitus and pulmonary hypertension, intraoperative MAP < 60 mmHg and massive blood transfusion, and treatment with excessive therapeutic concentration of Tac within postoperative 1 week are the independent risk factors for the occurrence of AKI early after lung transplantation.

Objective To analyze the dynamic changes and the influencing factors of T lymphocyte subsets in recipients with stable graft status within 1 year after lung transplantation. Methods Clinical data of 41 recipients with stable graft status after allogeneic lung transplantation were analyzed. The absolute value and ratio of T lymphocyte subsets in peripheral blood from recipients were measured by flow cytometry before operation, 2 weeks and each month (within 1 year) after operation, respectively. The effects of age, gender, body mass index (BMI), surgical method, incidence of primary graft dysfunction (PGD) after operation, and primary disease upon the absolute values of T lymphocytes were evaluated. Results Within 1 year after lung transplantation, the absolute values of CD3⁺, CD3⁺CD4⁺, CD3⁺CD8⁺T lymphocytes and CD4⁺/CD8⁺ ratio were changed over time (all P < 0.001). Compared with preoperative values, there was no statistical significance in the absolute values of CD3⁺ and CD3⁺CD4⁺T lymphocytes at 12 months after operation (P=0.659, 0.109), whereas the absolute value of CD3⁺CD8⁺T lymphocytes was increased (P=0.02) and the CD4⁺/CD8⁺ ratio was decreased (P < 0.001). Age, gender, BMI, surgical method and incidence of PGD after operation exerted no significant effect on the dynamic changes of absolute values of CD3⁺CD4⁺ and CD3⁺CD8⁺T lymphocytes (all P > 0.05). Primary disease before lung transplantation exerted no effect on the changes of CD3⁺CD4⁺T lymphocytes, whereas the postoperative absolute value of CD3⁺CD8⁺T lymphocytes was higher in recipients with infectious lung diseases (P < 0.05). Conclusions The absolute values of CD3⁺, CD3⁺CD4⁺, CD3⁺CD8⁺T lymphocytes in recipients with stable graft status after lung transplantation are relatively low in the early stage after lung transplantation, then gradually restore, and stabilize at 6 months after operation. Dynamic changes are not associated with age, gender, BMI, surgical method and incidence of PGD after operation of recipients.