Numerical research on disastrous mechanism of seepage instability of karst collapse column considering variable mass effect.

In order to reveal the disastrous mechanism of seepage instability of karst collapse column considering variable mass effect, a variable mass fluid-solid coupling mechanical model of water inrush is established, by considering the random distribution characteristics of a collapse column. Taking Qianjin coal mine as the research background, based on the Weibull distribution theory, the heterogeneous distribution characteristics of rock mass is described, and COMSOL Multiphysics numerical simulation software is employed to simulate the seepage characteristics and inrush water changes in collapse columns under different conditions of homogeneity, water pressure, and initial porosity. The research results show that the greater the homogeneity is, the more water conduction channels are formed, and the porosity increases accordingly, when considering the influence of different homogeneity on the seepage characteristics of broken rock mass, which eventually leads to water inrush accidents and a sharp increase in water inflow. Besides, when studying the seepage evolution law of different water pressures on a broken rock mass, an elevation of water pressure dramatically increases the porosity and seepage rate of the water. Over time, the broken rock particles gradually migrate and the fine particles are transported and eroded by the water flow, resulting in changes in the seepage characteristics and the formation of potential water diversion channels. Finally, when taking into account the effect of different initial porosity on the fractured rock mass seepage characteristics, the greater the original porosity is, the higher the seepage velocity is, and the particle migration increases the permeability. This leads to a more pronounced conductive water passage formation, which reveals the disastrous mechanism of seepage instability of karst collapse column considering variable mass effect.

Breaking law of overburden rock and key mining technology for narrow coal pillar working face in isolated island.

When conducting retreat mining in segmented coal pillars, the dynamic evolution of stress and overlying strata structure is more complex than conventional working faces due to the influence of adjacent working faces. Understanding and mastering the dynamic evolution patterns of overlying strata structure after retreat mining in segmented coal pillar working faces is essential for guiding the safe recovery of coal pillar resources under similar conditions. Through statistical analysis of the types of residual coal and the mining techniques, the current research status of residual coal mining system in China has been summarized. Based on the safety recovery technology system for multi-type residual coal pillar resources at Zhaogu No.2 Mine, this paper focuses on narrow coal pillar working faces in sections with fully mined-out areas on both sides. By using research methods such as on-site measurement, theoretical analysis, numerical simulation, and engineering experiments, starting from the stress state analysis and evolution law of coal seam mining, the dynamic evolution law of the overlying rock structure of sectional coal pillars has been mastered. On this basis, a stress arch mechanical model of the mining area is constructed, and the working resistance of the support is calculated and determined, ensuring the safe recovery of the working face. The research results show that before the backfilling of the sectional coal pillar working face, the working face is affected by the overlapping mining of the goaf on both sides, presenting a "bimodal" stress distribution pattern, with a stress concentration coefficient between 1.78 and 3.2. After the extraction of segmented coal pillars, stress arches consisting of high-stress zones form along both the strike and dip of the working face. The structural support provided by stress arches undergoes a dynamic evolution process of "formation-development-elevation-stabilization" as the working face advances. Following the instability and rupture of the lower basic roof hinge structure, the stress-bearing structure shifts to the higher basic roof, continuing to provide support for the surrounding rock stress in the mining space of the working face. A stress arch mechanical model for the dip and strike of the mining area is constructed , and the shape characteristics of the overlying rock stress arch in the coal pillar working face is mastered. Based on the stress distribution law and stress arch evolution characteristics of the surrounding rock of the coal pillar working face, the maximum working resistance of the support in the working face is theoretically calculated to be 9153.48kN. Compared with the measured mine pressure data, the selected support effectively ensures the safety production of the working face.

Research on overburden structural characteristics and support adaptability in cooperative mining of sectional coal pillar and bottom coal seam.

In the mining process of the II1 coal seam at Zhaogu No. 2 coal mine, a method of stratified mining is employed, leaving relatively wide coal pillars in sections. To enhance the resource recovery rate, the mine carries out the cooperative mining of the sectional coal pillars and the lower layer coal seam. The 14,022 cooperative working face of fully-mechanized and fully-mechanized top-coal caving at Zhaogu No. 2 coal mine is taken as the research object. Through numerical simulation, theoretical calculations, and on-site industrial trials, a comprehensive analysis of the overburden structural characteristics and the support adaptability at the working face is conducted. It is clarified that a stress arch bearing structure can be formed above the sectional coal pillars during cooperative mining, and this structure is controlled by key strata. The formation of a stress arch bearing structure in the overburden above the sectional coal pillars provides protection for the underlying mining area. A formula for calculating the working resistance of hydraulic supports under the stress arch in sectional coal pillar is derived. Based on these results, the working resistance of hydraulic supports in the coal pillar area is calculated and selected. Field application shows that the working resistance of the support is 10,000 kN in the fully-mechanized top-coal caving working face, and is 9000 kN in fully-mechanized working face, meeting the support requirements and ensuring safe mining at the working face. This study provides a valuable engineering reference for achieving cooperative mining of abandoned sectional coal pillars and lower layer coal seam in stratified mining method.

Fracture propagation and pore pressure evolution characteristics induced by hydraulic and pneumatic fracturing of coal.

A two-dimensional unsteady seepage model for coal using a finite element program is developed, and the temporal variations of key factors such as water pressure and hydraulic gradient are analyzed in this paper. Additionally, the triaxial rock mechanical experiment and utilized pneumatic fracturing equipment on raw coal samples to investigate both hydraulic and pneumatic fracturing processes are conducted. Through these experiments, the relationship between pressure and crack formation and expansion are examined. The analysis reveals that the pore pressure gradient at the coal inlet reaches its peak during rapid surges in water pressure but diminishes over time. Conversely, the pore pressure gradient at the outlet side exhibits a gradual increase. Hydraulic fracturing is most likely to occur at the water inlet during sudden increases in water pressure. Besides, as the permeability of coal decreases, the duration for seepage stabilization prolongs due to the intensified pore pressure gradient resulting from sudden increases in water pressure. Moreover, an extended period of high hydraulic gradient further increases the risk of hydraulic fracturing. The experimental findings indicate that coal samples initially experience tensile failure influenced by water and air pressure. Subsequently, mode I cracks form under pressure, propagating along the fracture surface and becoming visible. The main types of failure observed in hydraulic and pneumatic fracturing are diametrical tensile failure, and the development of fractures can be categorized into three distinct stages, which contains the initial stage characterized by slight volume changes while water pressure increases, the expansion stage when pressure reaches the failure strength, and the crack closure stage marked by little or even decreasing volume changes during pressure unloading. The acoustic emission signal accurately corresponds to these three stages.

Nonlinear evolution characteristics and seepage mechanical model of fluids in broken rock mass based on the bifurcation theory.

With the deep extension of coal mining in China, fault water inrush has become one of the major disasters threatening the safety production of coal mine. Based on the control equations of steady state and non-Darcy seepage in fractured rock mass, the multi-parameter nonlinear dynamic seepage equations of fractured rock mass are established in this paper. Based on the nonlinear dynamics theory, the function of the state variable in the system is derived, and the influence of the gradual change of non-Darcy flow factors on the structural stability of seepage system is studied. The research achievements show that there are three branches in the equilibrium state of the seepage system. Specifically, the stability of the equilibrium state changes abruptly near the limit parameter. The seepage dynamic system of fractured rock mass has the delayed bifurcation, and the coal mine disaster such as fault water inrush occurs easily at the bifurcation point. The research results are of great significance to enrich the theory of fault water inrush in coal mine, and to reveal the disastrous mechanism of fault water inrush and guide its prevention and control technology in coal mine, which can provide the theoretical reference for predicting the water seepage stability in fractured rock mass.

Seepage evolution characteristics and water inrush mechanism in collapse column under mining influence.

To obtain the seepage evolution rule and water inrush mechanism of the collapse column, a multi-field coupled mechanical model for water inrush disasters caused by the collapse column is established in this paper, on the basis of the specific engineering conditions of the 1908 working face in the Qianjin coal mine. The mechanical model is composed of internal column elements within the collapse column and surrounding rock masses. The research focuses on the seepage evolution rule in the roof collapse column under different mining conditions and investigates the permeation instability mechanism of collapse column based on the transition of flow state. The research results indicate that the seepage pathway evolves continuously, ultimately forming a channel for water inrush, as the working face advances towards the collapse column. Besides, the water inflow increases rapidly when the working face advances 100 m, then gradually stabilizes, indicating that the seepage channel entry of the collapse column is in a stable stage. Meanwhile, mass loss in the collapse column gradually moves upward. the collapse column remains stable as a whole in the initial stage of water flow, with a small permeability, exhibiting linear flow. As time steps increases, particle loss in collapse column gradually extends to the upper part, forming a stable seepage channel. The flow velocity shows fluctuations with a slow declining trend over time.

Evolution mechanism of water-conducting fractures in overburden under the influence of water-rich fault in underground coal mining.

Based on the 7618 working face in Yaoqiao coal mine of Datun mining area, the activation mechanism of water-rich faults and the development characteristics of water-conducting fractures in overlying strata under the influence of faults are studied by theoretical analysis, numerical simulation and field measurement in this paper. The research results show that Anderson model and Mohr-Coulomb strength criterion are combined to establish the fault failure mechanical model, and the fault activation criterion under the influence of mining is obtained. FLAC3D numerical simulation results show that with the advance of the working face, the fault begins to be affected by the mining effect of the working face at the distance of 20 ~ 30 m from the fault. Meanwhile, with the advance of the working face, the overburden shear failure range also expands, and the fault fracture gradually expands from top to bottom. The failure zone of the working face roof is connected with the fault fracture zone. Then the fault is "activated" and causes the fault to become a water gushing channel, and finally the water gushing disaster occurs. Through numerical simulation and comparative analysis, the development height of water-conducting fracture is 73.2 m in the absence of fault, and 73.7 m in the presence of fault, indicating that the fault has little influence on the maximum development height of water-conducting fracture. The actual development height of the water-conducting fracture zone in the 7618 working face is 73.97 m and the fracture production ratio is 13.7. The research results can provide theoretical reference for the safe mining of similar working faces across faults.

Experimental research on mechanical performance of grouting plugging material with large amount of fly ash.

In order to achieve the purpose of long-term stable mining of roadway, the strength and stability of rock mass are improved by means of grouting of fractured rock mass. In this paper, orthogonal test and numerical simulation methods were used to study the plugging performance of large amount of fly ash grouting slurry. The fluidity, water separation rate, compressive strength, setting time, stone rate and viscosity of the slurry were analyzed, and the optimal slurry ratio scheme was obtained. Under the optimal ratio scheme, the slurry transport process of the fractured rock mass was simulated, and the dynamic evolution law of the permeability of the slurry in the fractured rock mass was obtained. The study shows that the proportions of fly ash, ordinary Portland cement, loess, accelerant, expansion agent, bentonite water reducer and solidifying agent were 52.65%, 27.70%, 13.85%, 3%, 0.7%, 0.8%, 0.6% and 0.7% in the slurry ratio scheme, respectively. The slurry migration in the fractured rock mass experienced three stages, namely the filling and diffusion stage, the percolation and deposition stage and the sealing stage. The initial permeability was 971.9 mD and decreased to 45.79 mD after 1800 s, with a decrease of 95.3%. The slurry sealing performance was significantly improved, which has certain guiding significance for the application of underground grouting reinforcement engineering.

Migration mechanism of grouting slurry and permeability reduction in mining fractured rock mass.

In order to solve the water and gas discharge hazard caused by gob water and harmful gases (such as CO), the method of grouting overburden fractures is adopted to achieve the purpose of safe and efficient mining production in coal mines. This paper carries out the experimental research on the permeability reduction effect of grouting in fractured rock mass, expounds the relationship between gas flow rate and pressure gradient, seepage pressure and permeability, confining pressure and permeability, and analyzes the permeability change law of fractured rock mass before and after grouting. Besides, the grouting migration and permeability reduction model of fractured fine-grained sandstone is constructed by combining grouting test and numerical simulation, which reveals the dynamic evolution law of rock mass permeability in the grouting process. The results show that the permeability of the grouting rock sample decreases from 700-13,000 to 15-300 mD than that of the ungrouting rock sample, and the decrease is more than 95%, which indicates that the sealing performance of grouting slurry is better. Besides, numerical simulations show that the initial permeability of rock samples is 971.9 mD, and the permeability decreases to 45.79 mD after 1800s, and the permeability decreases to 95.3%, which is basically consistent with the experimental results after grouting. The greater the grouting pressure is, the better the grouting effect is. With the increase of the grouting pressure, the increase of the grouting effect is no longer obvious.

Abnormal ore pressure mechanism of working face under the influence of overlying concentrated coal pillar.

Shenfu Dongsheng coal field is a cross-century energy base which is developed and constructed in China. In recent years, some mines have successively entered to the coal seam of the second layer. Due to the reasons of early mining, many coal pillars are left in the coal seam of the first layer, resulting in the phenomenon of strong ore pressure in the mining range before and after the coal pillar in the lower coal seam and even causing the buckling accident. In order to solve such safety problems, this paper takes the 22,307 working face in Bulianta coal mine as the research object, adopts physical similarity simulation experiment and theoretical analysis to systematically study the overlying rock characteristics and abnormal ore pressure manifestation mechanism of shallow and close coal seam in different working stages. The results show that the roof overburden of the key layer in the lower group bends and sinks when the coal pillar is mined, resulting in the activation and instability of the "masonry beam" structure formed by the roof of the upper coal seam. When the coal pillar is discharged, the residual concentrated coal pillar and the room type coal pillar are unstable under the action of high supporting stress, resulting in shear failure of the inter-layer rock in the upper part of 22,307 working face, causing the strong dynamic pressure of the working face to appear and then leading to the buckling accident. The working resistance of the support in each stage is obtained by establishing the structure diagram of the overlying rock under each stage and the corresponding mechanical structure model. Finally, the working resistance required by the support in the mining stage under the goaf is 16,692.6 kN, the working resistance required by the support in the coal pillar stage is 19,692.6 kN, the working resistance required by the support in the mining stage under the concentrated coal pillar is 13,150.6 kN, and the working resistance required by the support in the coal pillar stage is 19,215.6 kN.

Research on slurry diffusion and seepage law in mining overburden fractures based on CFD numerical method.

It is of great theoretical significance and engineering application value to research the diffusion law of slurry in mining fractures of rock strata to enrich grouting theory and improve grouting sealing effect. In this paper, the law of grout diffusion in fractures under different working conditions is systematically explored and analyzed, and a numerical simulation scheme of grout diffusion in a single slab crack is established. Then, the diffusion law of grouting slurry in crack under different rheological index and different consistency index is further investigated. The results show that the diffusion time of grouting slurry has no relation with the rheological index. The grout pressure at the same point increases with the increase of rheological index. When the rheological index increases by 0.1, the grout pressure increases by about 12.5%. The closer the grouting mouth is, the more the grouting pressure is affected by the rheological index. There is little relationship between the diffusion time of grouting slurry and consistency index. The grout pressure at each measurement point increases with the increase of the consistency index. When the consistency index increases by 1, the grout pressure increases by about 15% on the basis of the origin. The closer the grouting mouth is, the more the grouting pressure is affected by the consistency index. In engineering practice, when grouting slurry with large rheological index or consistency index exists, it is necessary to moderately increase the grouting pressure value.

Conversion to thoracotomy during minimally invasive esophagectomy: Retrospective analysis in a single center / 中国胸心血管外科临床杂志

@#Objective     To explore the causes of conversion to thoracotomy in patients with minimally invasive esophagectomy (MIE) in a surgical team, and to obtain a deeper understanding of the timing of conversion in MIE. Methods     The clinical data of patients who underwent MIE between September 9, 2011 and February 12, 2022 by a single surgical team in the Department of Thoracic Surgery of the Fourth Hospital of Hebei Medical University were retrospectively analyzed. The main influencing factors and perioperative mortality of patients who converted to thoracotomy in this group were analyzed. Results     In the cohort of 791 consecutive patients with MIE, there were 520 males and 271 females, including 29 patients of multiple esophageal cancer, 156 patients of upper thoracic cancer, 524 patients of middle thoracic cancer, and 82 patients of lower thoracic cancer. And 46 patients were converted to thoracotomy for different causes. The main causes for thoracotomy were advanced stage tumor (26 patients), anesthesia-related factors (5 patients), extensive thoracic adhesions (6 patients), and accidental injury of important structures (8 patients). There was a statistical difference in the distribution of tumor locations between patients who converted to thoracotomy and the MIE patients (P<0.05). The proportion of multiple and upper thoracic cancer in patients who converted to thoracotomy was higher than that in the MIE patients, while the proportion of lower thoracic cancer was lower than that in the MIE patients. The perioperative mortality of the thoracotomy patients was not significantly different from that of the MIE patients (P=1.000). Conclusion     In MIE, advanced-stage tumor, anesthesia-related factors,extensive thoracic adhesions, and accidental injury of important structures are the main causes of conversion to thoracotomy. The rate varies at different tumor locations. Intraoperative conversion to thoracotomy does not affect the perioperative mortality of MIE.

Clinical application of Grunenwald incision in cervicothoracic junction surgery / 中华胸心血管外科杂志

Objective:To investigate the clinical application of Grunenwald incision in cervicothoracic junction surgery.Methods:The clinical data of 25 patients with cervicothoracic junction tumor and 1 patient with cervicothoracic junction trauma in the single treatment group of Department of Thoracic Surgery, the Fourth Hospital of Hebei Medical University from December 2011 to September 2021 were analyzed retrospectively, including 19 males and 7 females, aged 9-73 years old. Among the 26 patients, there were 9 cases of upper mediastinal tumor, 6 cases of superior sulcus tumor, 4 cases of thyroid tumor invading the upper mediastinal, 4 cases of chest wall tumor, 2 cases of esophageal cancer combined with supraclavicular lymph node metastasis, and 1 case of foreign body penetrating injury at the cervicothoracic junction. Grunenwald incision or additional posterolateral thoracic incision, median sternal incision, neck collar incision were used in all patients. The degree of tumor resection was evaluated. The operation time, intraoperative blood loss, length of hospital stay were observed, and the postoperative follow-up was analyzed.Results:There was no perioperative death in the whole group. 14 cases were treated with Grunenwald incision alone, 6 cases with additional posterolateral chest incision, 4 cases with additional neck collar incision, and 2 cases with additional median sternal incision. The tumors were completely resection in 22 cases, palliative tumor resection in 3 cases, and complete foreign body removal in 1 case. Postoperative pathology included 4 cases of schwannoma; 3 cases of lung adenocarcinoma, thyroid cancer and myofibroblastoma, respectively; 2 cases of supraclavicular lymph node metastasis of esophageal cancer and lung squamous carcinoma, respectively; 1 case of large cell neuroendocrine carcinoma, metastatic carcinoma of the first rib after lung squamous cell carcinoma, ganglioneuroma, nodular goiter, hemangioma, well differentiated liposarcoma, vascular endothelial tumor and cavernous angioma, respectively. The operation time was 120-430 min, with a mean of(226.92±88.40)min. The intraoperative blood loss was 100-1 000 ml, with a mean of(273.46±196.34)ml. The length of hospital stay was 6-26 days, with a mean of(12.73±4.46 )days. 26 patients were followed up for 6-130 months, with a mean of(57.88±43.64) months. During the follow-up period, 6 patients died.Conclusion:Grunenwald incision can provide good exposure of the structures near the cervicothoracic junction, preserve the integrity of sternoclavicular joint, reduce shoulder deformity, and has advantages for patients with cervicothoracic junction tumors, high rib resection, and cervicothoracic junction trauma.

Aureane-type sesquiterpene tetraketides as a novel class of immunomodulators with interleukin-17A inhibitory activity

Interleukin (IL)-17A, a pro-inflammatory cytokine, is a fundamental function in the onset and advancement of multiple immune diseases. To uncover the primary compounds with IL-17A inhibitory activity, a large-scale screening of the library of traditional Chinese medicine constituents and microbial secondary metabolites was conducted using splenic cells from IL-17A-GFP reporter mice cultured under Th17-priming conditions. Our results indicated that some aureane-type sesquiterpene tetraketides isolated from a wetland mud-derived fungus, Myrothecium gramineum, showed remarkable IL-17A inhibitory activity. Nine new aureane-type sesquiterpene tetraketides, myrogramins A-I ( 1, 4- 11), and two known ones ( 2 and 3) were isolated and identified from the strain. Compounds 1, 3, 4, 10, and 11 exhibited significant IL-17A inhibitory activity. Among them, compound 3, with a high fermentation yield dose-dependently inhibited the generation of IL-17A and suppressed glycolysis in splenic cells under Th17-priming conditions. Strikingly, compound 3 suppressed immunopathology in both IL-17A-mediated animal models of experimental autoimmune encephalomyelitis and pulmonary hypertension. Our results revealed that aureane-type sesquiterpene tetraketides are a novel class of immunomodulators with IL-17A inhibitory activity, and hold great promise applications in treating IL-17A-mediated immune diseases.

Current status and prospect of biomarker research for schizophrenia / 中华检验医学杂志

Schizophrenia is a serious mental disease. The diagnosis of schizophrenia so far relies heavily on subjective evidence, including self-reported experiences by patients, manifestations described by relatives, and abnormal behaviors assessed by psychiatrists. The diagnosis, monitoring of the disease progression and therapy efficacy assessment are challenging due to the lack of established laboratory biomarkers. Based on the current literature, clinical consensus, guidelines, and expert recommendations, this review highlighted evidence-based potential laboratory biomarkers for the diagnosis of schizophrenia, including genetic biomarkers, neurotransmitters, neurodevelopmental-related proteins, and intestinal flora, and discussed the potential future directions for the application of these biomarkers in this field, aiming to provide an objective basis for the use of these biomarkers in the early and accurate diagnosis, treatment, and prognosis and rehabilitation assessment of schizophrenia.

Wenbu Gushen Recipe alleviates renal fibrosis and pyroptosis by down-regulating CTRP6 in rats with diabetic nephropathy / 中华内分泌代谢杂志

Objective:To explore the effect and mechanism of Wenbu Gushen Recipe on renal fibrosis and pyroptosis in diabetic nephropathy (DN) rats.Methods:Sixty SD rats were randomly divided into control group, model group, low, medium and high dose groups of Wenbu Gushen Decoction, irbesartan group with 10 rats each. Except for control group, other groups were given intraperitoneal injection of streptozotocin (60 mg/kg) to construct model the DN. The low-dose, middle-dose, and high-dose groups were given different doses of Wenbu Gushen(0.92, 1.84, and 3.68 g·kg -1·d -1) respectively, irbesarta group was gavaged with 13.5 mg·kg -1·d -1 of . The rats were given the same amount of normal saline in the control group and the model group. After 12 weeks of treatment, 24 hour urine protein, urea nitrogen, creatinine and blood glucose of each group of rats were measured; the pathological changes of rat kidneys were observed; The expression of collagen Ⅲ, transforming growth factor(TGF)-β1, pro-casapse-1, cleaved-caspase-1, GSDMD, GSDMD-N, interleukin(IL)-1β, IL-18, and C1q/tumor necrosis factor-related protein 6 (CTRP6) were detected in kidney tissues; ELISA to detect IL-1β, IL-18 concentration in serum. Results:Compared with control group, the 24 hour urine protein, urea nitrogen, creatinine and blood glucose were significantly increased in the model group; The kidney tissue showed obvious pathological changes, and the expression of TGF-β1, collagen Ⅲ, cleaved-caspase-1, GSDMD-N, IL-1β, IL-18 and CTRP6 were increased in renal tissues, accompanied with IL-1β and IL-18 concentration were increased in serum. Compared with the model group, Wenbu Gushen Decoction inhibited the above indicators and improve kidney injury.Conclusion:Wenbu Gushen Recipe has a protective effect on DN renal injury, and it may inhibit renal fibrosis and pyrpoptosis via down-regulation of CTRP6.

Clinicopathological characteristics and prognostic factors analysis of patients with esopha-geal cancer / 中华消化外科杂志

Objective:To investigate the clinicopathological characteristics and prognostic factors of patients with esophageal cancer.Methods:The retrospective case-control study was conducted. The clinicopathological data of 447 patients with esophageal cancer who were admitted to the Fourth Hospital of Hebei Medical University from January 1, 2017 to December 31, 2020 were collected. There were 312 males and 135 females, aged 60(range, 37?82)years. Observation indica-tors: (1) clinicopathological characteristics; (2) treatment; (3) follow-up; (4) analysis of prognostic factors for esophageal cancer. Follow-up using telephone interview or outpatient examination was conducted to detect survival of patients up to December 2021. The total survival time was from the surgery date to death or the last follow-up. Patients with duration of follow-up more than 2 years were included for survival and prognostic analysis. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(range). Count data were represented as absolute numbers. Kaplan-Meier method was used to draw survival curves and calculate survival rates. Log-Rank test was used for survival analysis. Univariate analysis was conducted using the Log-rank test. Multivariate analysis was conducted using the COX hazard regression model. Results:(1) Clinicopathological characteristics. Of the 447 patients, 69.80%(312/447) were males and 30.20%(135/447) were females, and there were 3, 18, 101, 229, 93, 3 cases aged 30?39 years, 40?49 years, 50?59 years, 60?69 years, 70?79 years, 80?89 years, respectively. About the pathological type, there were 424 cases with squamous carcinoma, 11 cases with small cell carcinoma, 4 cases with adenosquamous carcinoma, 3 cases with sarco-matoid carcinoma, 2 cases with adenocarcinoma, 1 case with neuroendocrine carcinoma, 1 case with undifferentiated carcinoma, and 1 case with adenoid cystic carcinoma. There were 2 cases with tumor located at cervicothoracic segment, 49 cases with tumor located at upper thoracic segment, 273 cases with tumor located at mid-thoracic segment, and 123 cases with tumor located at lower thoracic segment. There were 6, 24, 74, 59, 192, 80, 12 cases in stage pT0, pT1a, pT1b, pT2, pT3, pT4a, pT4b of pathological T staging, respectively. There were 207, 63, 142, 28, 7 cases in stage pN0, pN1, pN2, pN3, pN4 of pathological N staging by Japan Esophagus Society (JES), respectively. There were 207, 128, 76, 36 cases in stage pN0, pN1, pN2, pN3 of pathological N staging by Union for International Cancer Control (UICC), respectively. About TNM staging, there were 25, 53, 127, 174, 68 cases in stage 0, Ⅰ, Ⅱ, Ⅲ, Ⅳa of JES staging, and 16, 9, 53, 35, 108, 96, 45, 85 cases in stage 0, Ⅰa, Ⅰb,Ⅱa, Ⅱb, Ⅲa, Ⅲb, Ⅲc of UICC staging, respectively. (2) Treatment. Of the 447 patients, 63 cases underwent neoadjuvant therapy(12 cases combined with immunotherapy), 384 cases underwent no neoadjuvant therapy. There were 347, 97, 2, 1 cases with surgical approach as right thoracic approach, left thoracotomy approach, cervical abdominal approach, left thoracoabdominal approach, respectively. There were 316, 5, 126 cases with surgical platform as totally endoscopic esophagec-tomy, Hybrid surgery, open surgery, respectively. There were 350 and 97 cases with digestive recons-truction as posterior mediastinal approach and intrathoracic approach, respectively. Surgical margin as R 0, R 1, R 2 resection was detected in 323, 116, 8 cases, respectively. Six of 447 patients died during the hospital stay. (3) Follow-up. All the 447 patients were followed up for 25(range, 2?48)months, including 233 cases with the follow-up more than 2 years. The median survival time of 233 patients was unreached, and the postoperative 2-year survival rate was 76.8%. (4) Analysis of prognostic factors for esophageal cancer. Results of univariate analysis showed that gender, neoadjuvant therapy, surgical margin, pT staging, pN staging by JES, pN staging by UICC, TNM staging by JES, TNM staging by UICC were related factors influencing prognosis of 233 patients with esophageal cancer ( χ2=6.62, 17.81, 32.95, 37.93, 27.06, 35.56, 45.24, 37.84, P<0.05). Results of multivariate analysis showed that gender, surgical margin, TNM staging by JES were independent factors influencing prognosis of 233 patients with esophageal cancer ( hazard ratio=0.48, 1.94, 1.46, 95% confidence intervals as 0.25?0.91, 1.07?3.52, 1.16?1.84, P<0.05). Conclusions:The incidence of esophageal cancer is relatively high in males, with the onset age mainly distribute in 60?69 years and the mainly pathological type as squamous carcinoma. Patients with esophageal cancer have advanced tumor staging, low proportion of neoadjuvant therapy, high R 0 resection rate of surgical treatment. Gender, surgical margin, TNM staging by JES are independent factors influencing prognosis of patients with esophageal cancer.

Reasons for Conversion to Thoracotomy in 83 Cases during Video-assisted Thoracic Surgery Lobectomy: A Summary of 1,350 Consecutive Operations by A Single Surgical Team / 中国肺癌杂志

BACKGROUND@#Video assisted thoracic surgery (VATS) is the main surgical method for lung cancer. The aim of this study was to analyze the reasons for conversion to thoracotomy in 83 cases among 1,350 consecutive cases who underwent video-assisted thoracic surgery (VATS) lobectomy by a single surgical team, in order to achieve a deeper understanding of the rules and the opportunity for conversion to thoracotomy in VATS lobectomy under normal conditions.@*METHODS@#The clinical data of 1,350 patients who underwent VATS lobectomy between September 21, 2009 and June 1, 2020, by a single surgical team in the Fifth Department of Thoracic Surgery of the Fourth Hospital of Hebei Medical University were retrospectively analyzed. There were 773 males and 577 females, aged 8-87 years, with a median age of 61.3 years, including 83 cases of benign diseases, 38 cases of lung metastases, and 1,229 cases of primary lung cancer. The cases with stage I, II and IIIa were 676, 323 and 230, respectively. The cases of left upper, left lower, right upper, right middle, right lower, right middle and upper and right middle and lower lobectomy were 301 (22.30%), 231 (17.11%), 378 (28.00%), 119 (8.81%), 262 (19.41%), 16 (1.19%) and 43 (3.19%), respectively.@*RESULTS@#In the cohort of 1,350 consecutive patients with VATS lobectomy, 83 patients (6.15%) were converted to thoracotomy for different reasons. The conversion rate of benign lesions was significantly higher than that of malignant tumors (P<0.05). The conversion rate in stage IIIa was significantly higher than that in stage I and II (P<0.05). The conversion rate of combined lobectomy was significantly higher than that of single lobectomy (P=0.001). The conversion rate of left upper lobectomy was significantly higher than that of other single lobectomy (P<0.001). The conversion rate of right middle lobectomy was significantly lower than that of other single lobectomy (P=0.049). The main reasons for conversion were vascular injury (38.55%), lymph node interference (26.51%) and dense adhesion in thoracic cavity (16.87%). In the conversion group, the total operation time was (236.99±66.50) min and the total blood loss was (395.85±306.38) mL. The operation time in patients converted to thoracotomy due to lymph node interference was (322.50±22.68) min, which was significantly longer than that in the other groups (P<0.05). The intraoperative blood loss in patients converted to thoracotomy due to vascular injury was (560.94±361.84) mL, which was significantly higher than that in the other groups (P<0.05). With the increase in surgical experience, the number of vascular injuries gradually decreased at the early stage, mid-stage and late stage (P=0.045).@*CONCLUSIONS@#In VATS lobectomy, benign lung lesions and more advanced malignant tumors led to more surgical difficulties and higher conversion rate. The conversion rate was different in different lobectomy sites, with the highest in left upper lobectomy, and the lowest in right middle lobectomy. Vascular injury, lymph node interference and dense adhesion were the main reasons for conversion to thoracotomy, which led to prolonged operation time and increased blood loss. With the increasing number of surgical cases, the rate of conversion to thoracotomy in VATS lobectomy continues to decline, which may be mainly due to the more advanced treatment of pulmonary vessels.

Effects of peripheral blood CD34 + cells count on the collection timing and results of peripheral blood stem cells / 肿瘤研究与临床

Objective:To investigate the variation trend of peripheral blood CD34 + cells during the hematopoietic stem cell mobilization and its influence on the collection timing and results. Methods:The clinical data of 62 patients with hematologic diseases undergoing autologous peripheral blood hematopoietic stem cell mobilization from April 2012 to March 2017 in Shanxi Provincial Cancer Hospital were analyzed. Mobilization regimen used chemotherapy combined with granulocyte colony-stimulating factor (G-CSF) to monitor the number of white blood cells (WBC), mononuclear cells (MNC), CD34 + cells in peripheral blood and apheresis concentrates, and the correlation with CD34 + cells was analyzed. Furthermore, the receiver operating characteristic (ROC) curve was used to establish the threshold to start apheresis. Results:MNC (5.66±1.11)×10 8/kg and CD34 + cell count (2.15±1.20)×10 6/kg were obtained in 62 patients who received 136 times collection in total. The peak of peripheral blood CD34 + cells count appeared at day 4-5 after the treatment of G-CSF, and then it went down. CD34 + cell count in the product was correlated with the peripheral blood CD34 + cell count collected on the day ( r = 0.879, P < 0.01), and it was also correlated with the peripheral blood WBC and MNC collected on the day as well as MNC count in the product (all P < 0.05). Furthermore, the ROC curve analysis demonstrated that peripheral blood CD34 + cells count > 23/μl was the optimal threshold for stem cell collection on the day, 85.2% of patients reaching up to the threshold could be successfully collected at one time. Conclusions:The variation trend of peripheral blood CD34 + cell count can guide the best time of stem cell collection in clinic. Peripheral blood CD34 + cell count is the reliable index to predict CD34 + cells count in the products. Peripheral blood CD34 + cells count > 23/μl could be used as the collection threshold.

Progress of day surgery techniques for varicose great saphenous vein / 国际外科学杂志

Varicose great saphenous vein is a common disease of vascular surgery. The treatment needs of a large number of patients and the progress of surgical techniques provide the necessity and feasibility for the active implementation of day surgery. Endovenous thermal closure techniques (laser closure and radiofrequency ablation) and non-thermal, non-tumescent techniques have the advantages of less trauma, faster recovery and fewer complications, and the effective rate and recurrence rate are not inferior to ligation and stripping. Sclerotherapy and phlebectomy are important auxiliary techniques.This paper analyzes and compares the technical characteristics and effectiveness of ambulatory surgeries for varicose great saphenous vein.