The Beila Ophiolite from the Bangong-Nujiang Suture Zone, Northern Tibetan Plateau

The Beila ophiolite is located in the middle part of the Bangong-Nujiang suture zone,northern Tibetan plateau.It is a complete ophiolite suite,and plays a key role in understanding the evolution of the Bangong-Nujiang suture zone,as well as the Meso-Tethys Ocean.The Beila ophiolite was composed of peridotite,serpentinite,gabbro,pillow basalt,and minor rodingite.Peridotites comprisemainlymedium–tocoarse–grained serpentinized harzburgites and minor plagioclase-bearing lherzolites and dunites.There are some felsic-ultramafic dykes within the peridotite and they are mainlypegmatoidal pyroxenites,coarse to fine-grained gabbros,and diabases.Gabbros included isotropic and cumulate gabbros,and they commonly contain minor pegmatoidal gabbros veins.Pillow basalts and basaltic andesites overlaid on the margin of the serpentinized peridotites.Rodingite occurs as lenses and/or dykes within the host serpentinized peridotites.Zircon SHRIMP U–Pb dating for two rodingite samples yielded the ages ranging from172 to 164 Ma.Whole-rock geochemical and zircon Hf isotopic data show that the Beila ophiolite shows SSZ-type ophiolite affinity.Finally,we suggest that the Beila ophiolite was generated in an initial subduction process at the middle Jurassic(164–172 Ma).

The Characteristics of Yongzhu–Guomang Lake Ophiolitic Melange in Bangong-Nujiang Suture, Xizang(Tibet),China

Yongzhu–Guomang Lake ophiolitic melange exposed about 100 km with large scale and complete ophiolitic uint in Xainza County,Xizang(Tibet).It is connected with Nam Lake,Kaimeng ophiolitic mélange to the east,and

Variation of Moho Depth across Bangong-Nujiang Suture in Central Tibet—Results from Deep Seismic Reflection Data

There is a long-term dispute at Moho depth across the Bangong-Nujiang suture (BNS). Due to the complicated and changeable seismic geological condition, it is not easy to acquire images of the reflective Moho in central Tibet. In the support of the SinoProbe project, a series of deep seismic reflection profiles were conducted to image Moho structure across the BNS and the Qiangtang terrane. These profiles extend from the northern Lhasa terrane to the Qiangtang terrane crossing the BNS. Both shot gathers and migration data show clear Moho images beneath the BNS. The Moho depth varies from 75.1 km (~24 s TWT) beneath the northmost Lhasa terrane to 68.9 km (~22 s TWT) beneath southmost Qiangtang terrane, and rises smoothly to 62.6 km (~20 s TWT ) at ~28 km north of the BNS beneath the Qiangtang terrane. We speculate that the Moho appears a 6.2 km sharp offset across the BNS and becomes ~12.5 km shallower from the northmost Lhasa terrane to the south Qiangtang terrane at ~28 km north of the BNS. The viewpoint of Moho depth across the BNS based on deep seismic reflection data is inconsistent with the previous 20 km offset.

The Cretaceous of the Eastern Bangong-Nujiang Suture Zone (Tibet):Tectono-Sedimentation

The ophiolite-bearing Bangong-Nujiang zone (BNZ) traversing central Tibet from east to west separates the Qiangtang block in the north from the Lhasa block in the south. The Cretaceous of the area includes Chuanba Formation (K 1c ), Duoba Formation (K 1d ), Langshan Formation (K 1l ) and Jiangba Formation (K 2j ). The K 1c is composed of black shale, sandy pelite, siltstone, sandstone, coal beds and volcanic rocks, of shallow marine facies. The K 1 d consists of terrestrial siliciclastics intercalated with some calcareous sandstone beds bearing Orbitolina sp. indicating marine influence. The K 1j is carbonate platform deposits of shallow marine and lagoon. The K 2j is characterized by terrestrial thick massive red conglomerate. An active margin related to B-subduction zone is considered to be the geological setting of the Cretaceous sedimentation.

Double-nylon purse-string suture in closing postoperative wounds following endoscopic resection of large(≥3 cm)gastric submucosal tumors

BACKGROUND Endoscopic full-thickness resection(EFTR)of gastric submucosal tumors(SMTs)is safe and effective;however,postoperative wound management is equally important.Literature on suturing following EFTR for large(≥3 cm)SMTs is scarce and limited.AIM To evaluate the efficacy and clinical value of double-nylon purse-string suture in closing postoperative wounds following EFTR of large(≥3 cm)SMTs.METHODS We retrospectively analyzed the data of 85 patients with gastric SMTs in the fundus of the stomach or in the lesser curvature of the gastric body whose wounds were treated with double-nylon purse-string sutures after successful tumor resection at the Endoscopy Center of Renmin Hospital of Wuhan University.The operative,postoperative,and follow-up conditions of the patients were evaluated.RESULTS All tumors were completely resected using EFTR.36(42.35%)patients had tumors located in the fundus of the stomach,and 49(57.65%)had tumors located in the body of the stomach.All patients underwent suturing with double-nylon sutures after EFTR without laparoscopic assistance or further surgical treatment.Postoperative fever and stomach pain were reported in 13(15.29%)and 14(16.47%)patients,respectively.No serious adverse events occurred during the intraoperative or postoperative periods.A postoperative review of all patients revealed no residual or recurrent lesions.CONCLUSION Double-nylon purse-string sutures can be used to successfully close wounds that cannot be completely closed with a single nylon suture,especially for large(≥3 cm)EFTR wounds in SMTs.

Early Triassic Volcanic Rocks in the Western Yarlung Zangbo Suture Zone:Implications for the Opening of the Neo-Tethys Ocean

In this study,zircon U-Pb dating of volcanic rocks from the Zhongba ophiolite of the Yarlung Zangbo Suture Zone(YZSZ)in southern Xizang(Tibet)yielded an age of 247±3 Ma.According to whole rock geochemical and Sr-NdPb isotopic data,the Early Triassic samples could be divided into two groups:Group 1 with P-MORB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70253–0.70602,ε_(Nd)(t)values of 4.2–5.3,(^(206)Pb/^(204)Pb)_(t)ratios of 16.353–18.222,(^(207)Pb/^(204)Pb)_(t)ratios of 15.454–15.564,and(^(208)Pb/^(204)Pb)_(t)ratios of 35.665–38.136;Group 2 with OIB affinity,showing initial^(87)Sr/^(86)Sr ratios of 0.70249–0.70513,ε_(Nd)(t)values of 4.4–4.9,(^(206)Pb/^(204)Pb)_(t)ratios of 17.140–18.328,(^(207)Pb/^(204)Pb)_(t)ratios of 15.491–15.575,and(^(208)Pb/^(204)Pb)_(t)ratios of 36.051–38.247.Group 2 rocks formed by partial melting of the mantle source enriched by a former plume,and assimilated continental crustal material during melt ascension.The formation of Group 1 rocks corresponds to the mixing of OIB melts,with the same components as Group 2 and N-MORBs.The Zhongba Early Triassic rocks belong to the continental margin type ophiolite and formed in the continental–oceanic transition zone during the initial opening of the Neo-Tethys in southern Xizang(Tibet).

Transcriptomic and cellular decoding of scaffolds-induced suture mesenchyme regeneration

Precise orchestration of cell fate determination underlies the success of scaffold-based skeletal regeneration.Despite extensive studies on mineralized parenchymal tissue rebuilding,regenerating and maintaining undifferentiated mesenchyme within calvarial bone remain very challenging with limited advances yet.Current knowledge has evidenced the indispensability of rebuilding suture mesenchymal stem cell niches to avoid severe brain or even systematic damage.But to date,the absence of promising therapeutic biomaterials/scaffolds remains.The reason lies in the shortage of fundamental knowledge and methodological evidence to understand the cellular fate regulations of scaffolds.To address these issues,in this study,we systematically investigated the cellular fate determinations and transcriptomic mechanisms by distinct types of commonly used calvarial scaffolds.Our data elucidated the natural processes without scaffold transplantation and demonstrated how different scaffolds altered in vivo cellular responses.A feasible scaffold,polylactic acid electrospinning membrane(PLA),was next identified to precisely control mesenchymal ingrowth and self-renewal to rebuild non-osteogenic suture-like tissue at the defect center,meanwhile supporting proper osteointegration with defect bony edges.Especially,transcriptome analysis and cellular mechanisms underlying the well-orchestrated cell fate determination of PLA were deciphered.This study for the first time cellularly decoded the fate regulations of scaffolds in suture-bony composite defect healing,offering clinicians potential choices for regenerating such complicated injuries.

Single self-leading suture technique for iridodialysis repairment

Dear Editor,We described an innovative“single self-leading suture technique”for repairing iridodialysis.Instead of moving the needle forth and back,our method is easier to manipulate in the narrow surgical space between the cornea and lens,which will decrease the unnecessary complications related to iatrogenic injury.We provide an economical friendly and less time-taking method,which improves the suture accuracy.

Intermittent sliding-lock-knot suture for limbal conjunctival autograft fixation in pterygium surgery:a technique note

AIM:To report a technique used with intermittent slidinglock-knot(ISLK)fixation for limbal conjunctival autografts in pterygium surgery and compared with those of routine intermittent(RI)fixation.METHODS:Consecutive patients with primary pterygium who had undergone pterygium excision combined with limbal conjunctival autograft transplantation between March 2021 and March 2022 at our institute were retrospectively analyzed.Primary outcome measures were mean duration of surgery and suture removal,degree of conjunctival hyperemia on postoperative day 1,pain score at suture removal,postoperative symptoms at 6mo,including conjunctival hyperemia,foreign body sensation,and graft stability.RESULTS:Ninety-eight patients underwent monocular surgery and were divided into ISLK(51 eyes)and RI(47 eyes)groups according to the type of conjunctiva autograft fixation method planned.There was no significant difference in mean duration of surgery between the two groups(18.59±2.39min vs 18.15±2.20min,P=0.417);however,compared to the RI group,shorter suture removal times were observed in the ISLK group[0.58min(0.42-0.87)vs 3.00min(2.21-4.15),P<0.001].The degree of conjunctival hyperemia on postoperative day 1 was milder in the ISLK group(P<0.001).Pain scores at suture removal were lower in the ISLK group than in RI group[1(0-3)vs 2(1-4),P<0.001].Postoperative symptoms at 6mo were comparable between the groups(P=0.487),with no recurrence.CONCLUSION:ISLK is an innovative method for limbal conjunctival autograft fixation after pterygium excision.Compared to RI fixation,ISLK facilitates suture removal and reduces discomfort,with comparable surgery duration and less conjunctival hyperemia.

Outcomes of a non-randomised audit of single pigtail suture stents in urolithiasis management of Asian patients in Singapore

Objective:Double-J(DJ)ureteric stents are commonly placed perioperatively for semirigid or flexible ureteroscopic renal surgery.It is believed that lesser stent material within the bladder mitigates stent-related symptoms.This study aimed to evaluate the J-Fil ureteral stent,a single pigtail suture stent compared with conventional DJ stent in relation to stent symptoms in an Asian population undergoing ureterorenal intervention.Methods:Based on internal audit committee recommendation approval,the records of 50 patients retrieved,available data of 41 patients who were prospectively enrolled into two groups(Group 1[J-Fil stent group],n=21 and Group 2[DJ stent group],n=20)between August 2020 to January 2021,were analysed.Parameters compared were nature of procedure,stone location and size,ease of deployment or removal,and complications.A modified universal stent symptom questionnaire was used to assess morbidity of stent symptoms within 48 h of insertion and at removal.Results:Both groups had similar median age,distribution in male to female ratio,and stone size.The overall median universal stent symptom questionnaire score at insertion was similar for bladder pain,flank or loin pain,and quality of life between Group 1 and 2;however,at removal Group 1 fared significantly better than Group 2,especially for flank or loin pain and pain at voiding.Both groups had similar ease in insertion with no hospital readmissions.Conclusion:Our audit favoured the single pigtail suture stent in Asian ureters in mitigating stent-related issues.It showed a good safety profile with easy deployment and removal.It promises a new standard in stenting.

Arthroscopic M-shaped suture fixation for tibia avulsion fracture of posterior cruciate ligament:A modified technique and case series

BACKGROUND Tibial avulsion fractures of the posterior cruciate ligament(PCL)are challenging to treat and compromise knee stability and function.Traditional open surgery often requires extensive soft tissue dissection,which may increase the risk of morbidity.In response to these concerns,arthroscopic techniques have been evolving.The aim of this study was to introduce a modified arthroscopic tech-nique utilizing an M-shaped suture fixation method for the treatment of tibial avulsion fractures of the PCL and to evaluate its outcomes through a case series.AIM To evaluate the effects of arthroscopic M-shaped suture fixation on treating tibia avulsion fractures of the PCL.METHODS We developed a modified arthroscopic M-shaped suture fixation technique for tibia avulsion fractures of the PCL.This case series included 18 patients who underwent the procedure between January 2021 and December 2022.The patients were assessed for range of motion(ROM),Lysholm score and International knee documentation committee(IKDC)score.Postoperative complications were also recorded.RESULTS The patients were followed for a mean of 13.83±2.33 months.All patients showed radiographic union.At the final follow-up,all patients had full ROM and a negative posterior drawer test.The mean Lysholm score significantly improved from 45.28±8.92 preoperatively to 91.83±4.18 at the final follow-up(P<0.001),and the mean IKDC score improved from 41.98±6.06 preoperatively to 90.89±5.32 at the final follow-up(P<0.001).CONCLUSION The modified arthroscopic M-shaped suture fixation technique is a reliable and effective treatment for tibia avulsion fractures of the PCL,with excellent fracture healing and functional recovery.

关节镜辅助下Suture-button弹性固定治疗高位踝关节扭伤

背景:高位踝关节扭伤容易漏诊导致踝关节功能障碍,关节镜检查可发现隐匿性高位踝关节扭伤,采用Suture-button弹性固定能恢复远端胫腓联合的生物力学稳定性。目的:探讨踝关节镜辅助下采用Suture-button弹性固定治疗高位踝关节扭伤的临床疗效。方法:回顾性分析2019年8月至2021年8月武汉市第四医院足踝外科在踝关节镜辅助下进行Suture-button弹性固定治疗的40例高位踝关节扭伤患者的病历资料。所有患者均采用Suture-button弹性固定,记录患者术前及术后末次随访美国矫形外科足踝协会踝-后足功能评分、目测类比疼痛评分、踝关节活动度,将患者术前影像学数据与术中关节镜下分离程度进行相关性分析,按照Meislin标准进行疗效评估并记录术后并发症发生情况。结果与结论:①40例患者术后获16-48个月随访;②术后末次随访美国矫形外科足踝协会踝-后足功能评分为(88.95±6.64)分,目测类比评分为(1.78±1.23)分,踝背伸活动度为(33.50±5.79)°,踝跖屈活动度为(34.50±5.97)°,与术前相比差异均有显著性意义(P<0.05);③影像学分离指标与关节镜下分离程度存在低度正相关(r=0.612,P<0.01);④采用Meislin标准对疗效进行评估,优良率为95%(38/40);术后踝关节疼痛减轻,踝关节自主活动明显改善;⑤随访期间所有患者均未出现神经损伤及切口感染情况;1例患者因术后存在皮肤刺激、下蹲卡顿感取出内固定;⑥提示采取关节镜辅助Suture-button弹性固定治疗高位踝关节扭伤的临床疗效确切,能够更有效地恢复患肢足踝功能,恢复并维持关节稳定性且无需二次取出,值得临床应用。

Comparison of modified gunsight suture technique and traditional interrupted suture in enterostomy closure

BACKGROUND Prophylactic enterostomy surgery is a common surgical approach used to reduce the risk of anastomotic leakage in patients who have undergone partial intestinal resection due to trauma or tumors.However,the traditional interrupted suturing technique used in enterostomy closure surgery has several issues,including longer surgical incisions and higher incision tension,which can increase the risk of postoperative complications.To address these issues,scholars have proposed the use of a“gunsight suture”technique.This technique involves using a gunsight incision instead of a traditional linear incision,leaving a gap in the center for the drainage of blood and fluid to reduce the risk of infection.Building on this technique,we propose an improved gunsight suture technique.A drainage tube is placed at the lowest point of the incision and close the gap in the center of the gunsight suture,which theoretically facilitates early postoperative mobility and reduces the burden of dressing changes,thereby reducing the risk of postoperative complications.AIM To compare the effectiveness of improved gunsight suture technique with traditional interrupted suture in closing intestinal stomas.METHODS In this study,a retrospective,single-center case analysis was conducted on 270 patients who underwent prophylactic ileostomy closure surgery at the Department of Colorectal Surgery of Qilu Hospital from April 2017 to December 2021.The patients were divided into two groups:135 patients received sutures using the improved gunsight method,while the remaining 135 patients were sutured with the traditional interrupted suture method.We collected data on a variety of parameters,such as operation time,postoperative pain score,body temperature,length of hospital stays,laboratory indicators,incidence of incisional complications,number of wound dressing changes,and hospitalization costs.Non-parametric tests and chi-square tests were utilized for data analysis.RESULTS There were no statistically significant differences in general patient information between the two groups,including the interval between the first surgery and the stoma closure[132(105,184)d vs 134(109,181)d,P=0.63],gender ratio(0.64 vs 0.69,P=0.44),age[62(52,68)years vs 60(52,68)years,P=0.33],preoperative body mass index(BMI)[23.83(21.60,25.95)kg/m²vs 23.12(20.94,25.06)kg/m²,P=0.17].The incidence of incision infection in the improved gunsight suture group tended to be lower than that in the traditional interrupted suture group[(n=2/135,1.4%)vs(n=10/135,7.4%),P<0.05],and the postoperative hospital stay in the improved gunsight suture group was significantly shorter than that in the traditional interrupted suture group[5(4,7)d vs 7(6,8)d,P<0.05].Additionally,the surgical cost in the modified gunsight suture group was slightly lower than that in the traditional suture group[4840(4330,5138)yuan vs 4980(4726,5221)yuan,P>0.05],but there was no significant difference in the total hospitalization cost between the two groups.CONCLUSION In stoma closure surgery,the improved gunsight technique can reduce the incision infection rate,shorten the postoperative hospital stay,reduce wound tension,and provide better wound cosmetic effects compared to traditional interrupted suture.

Proof of concept of a self-tightening needle-less suture using a NiTi shapememory alloy

Among surgical procedures,suturing is considered simple.However,in some situations,suturing is not easy or feasible.Here,we present proof of concept of a new self-tightening needle-less suture made of a NiTi alloy.The new device is designed to overcome two demanding steps of traditional suturing:needle introduction and manual knotting.Our novel suture is composed only of a short NiTi wire that is able to change shape by exploiting a thermoelastic phase transition.This shape change is achieved by increasing the temperature from that of the operating room(e.g.,20-22℃)to 32℃using warm water.Suturing consists of two steps:suture introduction,in which the suture is in an open configuration,and shape recovery(i.e.,closed configuration).The closed configuration is maintained at human body temperature thanks to peculiar pseudoelastic properties of the NiTi material.Finally,thermal and functional characterization verified the simplicity and effectiveness of the proposed device.

Efficacy of surgical resection and ultra-reduced tension suture combined with superficial radiation in keloid treatment

BACKGROUND There are many available treatment options for keloid;however,single treatments are usually less effective.Therefore,more scientifically rational and effective com-bined treatment methods should be sought to solve the pain associated with keloids.AIM To explore the efficacy and safety of surgical resection and ultra-reduced tension suture combined with superficial radiation as keloid treatment.METHODS Fifteen keloid patients admitted to Qingdao Eighth People's Hospital from June 2020 to January 2022 were enrolled in this retrospective analysis.All patients underwent a comprehensive treatment approach comprising surgical resection,ultra-reduced tension suture incision,and superficial radiation therapy within 24 h postoperatively.The modified Vancouver Scar Scale(mVSS)and Patient and Observer Scar Assessment Scale(POSAS)were used to evaluate the treatment effect,whereas the efficacy,adverse effects,and recurrence rate were observed according to the 12-mo follow-up after treatment.RESULTS The mVSS and POSAS scores at 1 and 6 mo after combination treatment decreased compared to before treatment(P<0.001),and the overall response rate was 93.3%.Only one case recurred,yielding a 6.7%recurrence rate.The incidence of local chromour sedimentation rate in 1–3 mo after radiotherapy was 33.3%(5 patients),all subsiding after 6–9 mo,without complications,such as delayed wound healing or dermatitis.CONCLUSION Surgical resection,super subtraction sutures,and superficial radiotherapy are treatment methods with short courses,low recurrence rates,and good safety profiles.

Gunsight suture with subcutaneous vacuum drainage during enterostomy decreased the surgical site infection rate in obese rectal cancer patients:A retrospective study

Background:Surgical site infection(SSI)is the most common complication after stoma closure and is particularly common in obese patients.To reduce the incidence of SSI,various skin closure techniques have been proposed;however,the best technique is still under debate.The purpose of this study was to explore the effectiveness of subcutaneous vacuum drains(SVDs)after two surgical suture techniques following stoma reversal in obese patients. Methods:Data from 190 obese patients with rectal cancer who underwent stoma reversal for enterostomy between February 2012 and April 2023 at Jinxiang Hospital Affiliated to Jining Medical University were retrospectively analyzed.These patients were divided into two groups:gunsight suture(GS)with SVD and primary linear suture(PLS)with SVD.The GS group and PLS group included 90 and 100 patients,respectively.The clinical characteristics and short-term outcomes were compared between the two groups.Postoperative pain scores were analyzed using a generalized estimation equation. Results:Surgery was successfully performed in both groups.The rate of SSI in the GS group was significantly lower than that in the PLS group(2.2%vs 9.0%,P=0.046).Patients in the GS group had a significantly shorter wound healing time than did patients in the PLS group,as well as a significantly shorter postoperative fasting time(P<0.05).No significant differences were found between the groups in terms of the postoperative hospital stay,operative time,and estimated blood loss(P>0.05).The results of the generalized estimation equation analysis showed that the GS group had significantly lower pain scores at 12,24,48,and 72 h after surgery than the PLS group(P<0.05).Moreover,the GS group showed significantly better alleviation of wound pain between 12 and 72 h after surgery(P<0.05). Conclusions:The GS technique with SVD may be recommended for wound closure of a nonfunctioning stoma in obese patients.

Bedside anterior segment optical coherence tomography-assisted reattachment of severe hemorrhagic Descemet’s membrane detachment after ab externo 360-degree suture trabeculotomy combined with trabeculectomy

Dear Editor,We report a case of severe hemorrhagic Descemet’s membrane detachment(HDD)following ab external360-degree suture trabeculotomy with trabeculectomy that was successfully managed with the guidance of bedside anterior segment optical coherence tomography(ASOCT).Descemet’s membrane detachment(DMD)is a complication that impairs vision and is commonly observed after cataract surgery.It’s reported a high incidence(25%-82%)of focal DMD that were mostly subclinical and detected only with gonioscopy[1].

Oxygen Penetration Through Full-Thickness Skin by Oxygen-Releasing Sutures for Skin Graft Transplantation

The transplantation of full-thickness skin grafts(FTSGs)is important for reconstructing skin barrier and promoting wound healing.Sufficient oxygen supply is closely related to the success of skin grafting.However,full-thickness oxygen delivery is limited by the poor oxygen permeability of skin.Oxygen-releasing sutures(O_(2)sutures)were developed to facilitate oxygen penetration through full-thickness skin.The O_(2)sutures delivered 100 times more oxygen than topical gaseous oxygen therapy at a 15 mm depth in the skin model.Under extreme hypoxia(<0.5%O_(2),v/v),O_(2)sutures could also promote endothelial cell proliferation.After the transplantation of FTSGs in mice,O_(2)sutures accelerated blood re-perfusion and increased the survival area of the skin graft.It is expected that O_(2)sutures will be adopted in clinical applications to increase the success rate of full-thickness skin transplantation.

Feasibility and efficacy of endoscopic purse-string suture-assisted closure for mucosal defects induced by endoscopic manipulations

BACKGROUND Large or transmural defects induced by gastrointestinal endoscopic manipulations are difficult to close,although complete closure is recommended for better recovery.Endoscopic purse-string assisted suturing(EPSS)has been used in clinical practice and has proven to be an effective and safe technique for the closure of large mucosal defects.However,details regarding the efficacy of endoscopic pre-purse-string suture(P-EPSS)are unknown,especially that it offers several advantages over conventional EPSS(C-EPSS).AIM To elucidate the outcomes of EPSS-assisted closure in different clinical situations,and evaluate the efficacy of P-EPSS.METHODS This retrospective observational study included a total of 180 patients who underwent closure assisted by P-EPSS(n=63)or C-EPSS(n=117)between July 2014 and June 2020.The P-EPSS and C-EPSS groups were compared and the intergroup differences in aspects such as the lesion size,location,and morphology,incidence of complete closure,intraoperative perforation,and delayed adverse events were evaluated.Data on the features and clinical course of cases with adverse events were collected for further analysis.RESULTS Patients with lesion size larger than 3 cm,lesions located at the fundus of stomach,or submucosal tumors originating from the deep mucosa were more likely to undergo P-EPSS-assisted closure.The P-EPSS group showed a significantly higher proportion of intraoperative perforation(56%vs 17%)and a much shorter procedure time(9.06±6.14 min vs 14.84±7.25 min).Among adverse events,the incidence of delayed perforation(5%vs 4%;P=0.82)and delayed bleeding(3%vs 4%;P=0.96)did not differ significantly between the groups.Multivariate analysis revealed that lesions with incomplete closure[odds ratio(OR)=21.33;95%confidence interval(CI):5.45-83.45;P<0.01]or size greater than 3 cm(OR=3.14;95%CI:1.08-9.18;P=0.039)showed a statistical tendency to result in an increase in delayed adverse events.CONCLUSION The present study revealed that EPSS could achieve secure complete closure of mucosal defect.PEPSS could shorten the procedure and yield complete closure of mucosal defects.Rather than closure-type selection,incomplete closure or lesion size larger than 3 cm were associated with worse outcomes.

Formation of South Tianshan suture and its geological significance

South Tianshan–Solonker suture,is the largest and southernmost suture within the Central Asian orogenic belt(CAOB).It records the ultimate collision between Tarim–North China cratons and Siberia craton,and is commonly interpreted as marking the eventual closure of Paleo-Asian Ocean.South Tianshan suture belongs to the western segment of the suture zone,and its evolutionary features are important for defining the formation age of the South Tianshan–Solonker suture.In this paper,the authors review the geochronological,geochemical,petrographic,and paleontological evidence within South Tianshan suture to delineate its formation era and closure characteristics,and thus further revealing the ultimate evolutionary pattern of the western segment of Paleo-Asian Ocean.This suture records strong plate collision before Late Carboniferous,forming a series of high-pressure metamorphic rocks,characterized by the presence of blue schist,eclogite and mica schist.In Permian,the whole area was under a relatively stable post-orogenic setting,with the formation of bimodal volcanic rocks,post-collisional granites,and terrestrial molasses.Sedimentary facies gradually changed from marine to either lacustrine or fluvial during this period.An Early Permian granite dike crosscuts the HP metamorphic belt,and the HP metamorphic rocks also underwent retrograde metamorphism at this time,indicating the formation of the South Tianshan suture was earlier than Permian.Hence,the western section of Paleo-Asian Ocean closed during Late Carboniferous,and Tarim Craton moved northward to collide with Kazakhstan–Yili Block,leading to the formation of the South Tianshan suture.