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.

How many sutures in the southern Central Asian Orogenic Belt:Insights from East Xinjiang-West Gansu(NW China)?

How ophiolitic mèlanges can be defined as sutures is controversial with regard to accretionary orogenesis and continental growth.The Chinese Altay,East junggar,Tianshan,and Beishan belts of the southern Central Asian Orogenic Belt（CAOB） in Northwest China,offer a special natural laboratory to resolve this puzzle.In the Chinese Altay,the Erqis unit consists of ophiolitic melanges and coherent assemblages,forming a Paleozoic accretionary complex.At least two ophiolitic melanges（Armantai,and Kelameili） in East Junggar,characterized by imbricated ophiolitic melanges,Nb-enriched basalts,adakitic rocks and volcanic rocks,belong to a Devonian-Carboniferous intra-oceanic island arc with some Paleozoic ophiolites,superimposed by Permian arc volcanism.In the Tianshan,ophiolitic melanges like Kanggurtag,North Tianshan,and South Tianshan occur as part of some Paleozoic accretionary complexes related to amalgamation of arc terranes.In the Beishan there are also several ophiolitic melanges,including the Hongshishan,Xingxingxia-Shibangjing,Hongliuhe-Xichangjing,and Liuyuan ophiolitic units.Most ophiolitic melanges in the study area are characterized by ultramafic,mafic and other components,which are juxtaposed,or even emplaced as lenses and knockers in a matrix of some coherent units.The tectonic settings of various components are different,and some adjacent units in the same melange show contrasting different tectonic settings.The formation ages of these various components are in a wide spectrum,varying from Neoproterozoic to Permian.Therefore we cannot assume that these ophiolitic melanges always form in linear sutures as a result of the closure of specific oceans.Often the ophiolitic components formed either as the substrate of intra-oceanic arcs,or were accreted as lenses or knockers in subduction-accretion complexes.Using published age and paleogeographic constraints,we propose the presence of （1） a major early Paleozoic tectonic boundary that separates the Chinese Altay-East Junggar multiple subduction systems of the southern Siberian active margin from those of the northern Tarim;and （2） a major Permian suture zone that separates the Tianshan-Beishan from the northern active margin of the Tarim Craton.These new observations and interpretations have broad implications for the architecture and crustal growth of central Asia and other ancient orogens as well.

Rejuvenation of Fossil Sutures and Related Mesozoic Intracontinental Orogenies in South China

The Huanan (South China) subcontinent was created by amalgamation of the Yangtze, Xianggan, Cathaysia and Zhemin microcontinents by the Guangxi orogeny in the Early Palaeozoic. The closure of the Tethyan Ocean and subsequent collision event outside the amalgamated continent reactivated fossil sutures and resulted in intracontinental (ensialic) orogenies in the Mesozoic. Based on evidence from deformation, molasse and granitoids, the Sichuan-Guizhou-Hunan—southern Hubei and Hunan-Jiangxi-Fujian Yanshanian fold-thrust systems and the Lower Yangtze-northwestern Fujian Indosinian fold-thrust system are thought to be intracontinental orogens. Their main features are as follows: intracontinental orogenies occurred areally, thrusting propagated towards the interior of the continental, they extend parallelly to the strikes of the fossil sutures, and the details of the temporal-spatial evolution of the orogens depend on subduction-collision events.

Genesis of Pyroxenite Veins in the Zedang Ophiolite,Southern Tibetan Plateau

Understanding the nature of parental melts for pyroxenite veins in supra-subduction zone(SSZ)ophiolites provides vibrant constraints on melt infiltration processes operating in subduction zones.The Zedang ophiolitic massif in the eastern Yarlung–Zangbo suture zone in Tibet consists of mantle peridotites and a crustal section of gabbro,diabase,and basalt.Veins of two pyroxenite varieties cut the southern part of the Zedang massif.These pyroxenite rocks have different geochemical characteristics,where the first variety(type-I)has relatively higher contents of SiO_(2)(51.82–53.08 wt%),MgO(20.08–23.23 wt%),andΣPGE(3.42–13.97 ppb),and lower Al_(2)O_(3)(1.59–2.28 wt%)andΣREE(1.63–2.94 ppm).The second pyroxenite variety(type-II)is characterized by SiO_(2)(45.44–49.61 wt%),Mg O(16.68–19.78 wt%),Al_(2)O_(3)(4.24–8.77 wt%),ΣPGE(14.46–322.06 ppb),andΣREE(5.82–7.44 ppm).Pyroxenite type-I shows N-MORB-like chondritenormalized REE patterns.Zircon U-Pb ages of pyroxenite type-I(194±10 Ma),associated ophiolitic gabbro(135.3±2.0 Ma),and plagiogranite(124.2±2.3 Ma)evidently imply episodic evolution of the Zedang ophiolites.The mineralogical and geochemical characteristics of the investigated pyroxenites can be explained by subduction-initiated hydrous melting of metasomatized sub-arc mantle,later overprinted by sub-slab mantle melting triggered by upwelling asthenosphere during the Jurassic–Early Cretaceous times.The geochemical variations in pyroxenite vein composition,coupled with age differences amongst the other ophiolite units,may correspond to intermittent emplacement of pyroxenite dikes and isotropic gabbroic intrusions where the geodynamic setting progressed from arc maturation and slab rollback to slab tearing and delamination.

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.

Outpatient hybrid endoscopic submucosal dissection with SOUTEN for early gastric cancer,followed by endoscopic suturing of the mucosal defect:A case report

BACKGROUND Although endoscopic submucosal dissection(ESD)is becoming more common for early gastric cancer,it requires more advanced techniques and a longer treatment duration than endoscopic mucosal resection.Hybrid ESD using a multifunctional snare(SOUTEN)has been reported to be effective for colorectal lesions,as it can reduce treatment duration.Endoscopic suturing of post-ESD mucosal defects has been reported to reduce the incidence of ESD-related complications.CASE SUMMARY This study reports outpatient hybrid ESD for early gastric cancer using SOUTEN,followed by endoscopic suturing of post-ESD mucosal defects in an 86-year-old man.On referral for ESD,a 10-mm flat,depressed lesion was found on the posterior wall of the gastric antrum,the depth of which was expected to be mucosal.Given his history of delirium,we performed outpatient endoscopic treatment.The procedure used was hybrid ESD using SOUTEN to reduce the duration of treatment and endoscopic suturing of post-ESD mucosal ESD defects to reduce complications.The procedure time was 62 min and the lesion was completely resected based on histopathological examination,with no reported postoperative complications.CONCLUSION This safe and useful procedure may be especially important for outpatient endoscopic treatment.

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.

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).

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.

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.

5-Bromo-2'-deoxyuridine labeling:historical perspectives,factors infiuencing the detection,toxicity,and its implications in the neurogenesis

The halopyrimidine 5-bromo-2′-deoxyuridine(BrdU)is an exogenous marker of DNA synthesis.Since the introduction of monoclonal antibodies against BrdU,an increasing number of methodologies have been used for the immunodetection of this synthesized bromine-tagged base analogue into replicating DNA.BrdU labeling is widely used for identifying neuron precursors and following their fate during the embryonic,perinatal,and adult neurogenesis in a variety of vertebrate species including birds,reptiles,and mammals.Due to BrdU toxicity,its incorporation into replicating DNA presents adverse consequences on the generation,survival,and settled patterns of cells.This may lead to false results and misinterpretation in the identification of proliferative neuroblasts.In this review,I will indicate the detrimental effects of this nucleoside during the development of the central nervous system,as well as the reliability of BrdU labeling to detect proliferating neuroblasts.Moreover,it will show factors influencing BrdU immunodetection and the contribution of this nucleoside to the study of prenatal,perinatal,and adult neurogenesis.Human adult neurogenesis will also be discussed.It is my hope that this review serves as a reference for those researchers who focused on detecting cells that are in the synthetic phase of the cell cycle.

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.

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.

Clinical Epidemiology and Surgical Treatment of Spontaneous Perforations of the Terminal Ileum: A Multicentre Study in Cameroon

Background: Perforations of the terminal ileum are a frequent clinical situation and a therapeutic challenge. Surgical treatment is controversial. Several surgical modalities have been proposed and postoperative morbidity and mortality remain high. The aim of this study was to review our experience in the surgical management of perforations of the terminal ileum. Patients and methods: This is a descriptive cross-sectional study with retrospective data collection from January 1, 2017 to December 31, 2021, in five hospitals in Cameroon. Patients’ demographic, clinical presentation, surgical findings and 30-days postoperative outcomes data were collected. Results: We collected 34 files. The sex ratio was 1.4 and the average age was 20.28 years. The average consultation time was 9.1 days. Abdominal pain was present in all our patients. Peritoneal irritation was present in 46 cases (88.5%). The mean time to treatment after admission was 17.5 hours. The perforation was unique in 40 cases (76.9%) and located between 6 and 10 cm from the ileocecal valve in 29 cases (55.8%). Typhoid was the most suspected etiology intraoperatively in 38 cases (73.1%). A simple suture was performed in 18 patients (34.6%), resection with anastomosis in 11 patients (21.2%) and an ileostomy in 5 patients (9.6%). The average length of hospitalization was 21.74 days. Postoperative morbidity and mortality were 32.7% and 17.3% respectively. Conclusion: Perforations of the terminal ileum are common and affect young people. Surgical procedures are varied. Reducing consultation and care times and respecting treatment principles could improve postoperative morbidity and mortality, which remain high.

V-Locsutures与普通可吸收线在后腹腔镜肾部分切除术中应用比较

目的:比较V-Loc sutures与普通可吸收线在后腹腔镜肾癌部分切除术中的应用价值。方法:2012年5月-2013年6月,本手术组共收治了25例确诊的病理分期为T1N0M0的肾癌患者,其中12例术中肾脏创面缝合均采用V-Loc sutures,其中男9例,女3例,年龄28-68岁,平均48.2岁;肿瘤大小为0.9-4.7cm,平均2.8cm;另13例术中采用普通可吸收线缝合创面,其中男8例,女5例,年龄34-74岁,平均45.5岁;肿瘤大小为1.2-4.5cm,平均2.6cm;比较两组患者手术中的手术时间、术中出血量、肾动脉阻断时间、创面缝合时间、各组手术前后测血肌酐、胱抑素C变化,术后并发症。结果:25例手术均在后腹腔镜下顺利完成。V-Loc sutures组和普通可吸收线组手术时间、术中出血、肾动脉阻断时间、肾创面缝合时间均有差异(P<0.05);V-Loc sutures组手术前后血肌酐、胱抑素C无明显差异(P>0.05),普通可吸收线组手术前后血肌酐、胱抑素C有差异(P<0.05);V-Loc sutures组出现1例血尿,普通可吸收线组出现1例漏尿。结论:V-Loc sutures较普通可吸收线可缩短手术时间及肾创面缝合时间,减少术中出血,更好的保护小肾癌患者的肾功能。

Can trans-anal reinforcing sutures after double stapling in lower anterior resection reduce the need for a temporary diverting ostomy?

AIM:To evaluate trans-anal reinforcing sutures in low anterior resection using the double-stapled anastomosis technique for primary rectal cancers performed at a single institution.METHODS:The data of patients who received transanal reinforcing sutures were compared with those of patients who did not receive them after low anterior resection.Patients who underwent laparoscopic low anterior resection and the double-stapled anastomosis technique for primary rectal cancer between January2008 and December 2011 were included in this study.Patients with no anastomosis,a hand-sewn anastomosis,high anterior resection,or preoperative chemoradiation were excluded.The primary outcomes measured were the incidence of postoperative anastomotic complications and placement of a diverting ileostomy.RESULTS:Among 110 patients,the rate of placement of a diverting ileostomy was significantly lower in the suture group(SG)compared with the non-suture control group(CG)[SG,n=6(12.8%);CG,n=19(30.2%),P=0.031].No significant difference was observed in the rate of anastomotic leakage[SG,n=3(6.4%);CG,n=5(7.9%)].CONCLUSION:Trans-anal reinforcing sutures may reduce the need for diverting ileostomy.A randomized prospective study with a larger population should be performed in the future to demonstrate the efficacy of trans-anal reinforcing sutures.

Basement of the South China Sea Area:Tracing the Tethyan Realm

The basement of the South China Sea（SCS）and adjacent areas can be divided into six divisions（regions）-Paleozoic Erathem graben-faulted basement division in Beibu Gulf,Paleozoic Erathem strike-slip pull-apart in Yinggehai waters,Paleozoic Erathem faulted-depression in eastern Hainan,Paleozoic Erathem rifted in northern Xisha（Paracel）,Paleozoic Erathem strike-slip extending in southern Xisha,and Paleozoic-Mesozoic Erathem extending in Nansha Islands（Spratly）waters.The Pre-Cenozoic basement in the SCS and Yunkai continental area are coeval within the Tethyan tectonic domain in the Pre-Cenozoic Period.They are formed on the background of the Paleo-Tethyan tectonic domain,and are important components of the Eastern Tethyan multi-island-ocean system.Three branches of the Eastern Paleo-Tethys tectonic domain,North Yunkai,North Hainan,and South Hainan sea basins,have evolved into the North Yunkai,North Hainan,and South Hainan suture zones, respectively.This shows a distinctive feature of localization for the Pre-Cenozoic basement.The Qiongnan（i.e.South Hainan）Suture Zone on the northern margin of the South China Sea can be considered the vestige of the principal ocean basin of Paleo-Tethys,and connected with the suture zone of the Longmucuo-Shuanghu belt-Bitu belt-Changning-Menglian-Bentong-Raub belt,the south extension of Bitu-Changning-Menglian-Ching Mai belt-Chanthaburi-Raub-Bentong belt on the west of South China Sea,and with the Lianhua-Taidong suture zone（a fault along the east side of Longitudinal Valley in Taiwan）-Hida LP/HT（low pressure-high temperature）metamorphic belt-Hida -marginal HP/LT metamorphic belt in southwestern Honshu of Japan,on the east of the South China Sea.The Qiongbei（North Hainan）suture zone may eastwards extended along the Wangwu-Wenjiao fault zone,and connects with the Lufeng-Dapu-Zhenghe-Shangyu（Lianhuashan）deep fault zone through the Pearl River Mouth Basin.The Meso-Tethys developed on the south of the South China Sea.The Nansha Trough may be considered the vestige of the northern shelf of the Meso-Tethys. The oceanic crust of the Meso-Tethys has southwards subducted along the subduction-collision-thrust southern margin of the Nansha Trough with a subduction-pole opposite to those of the Yarlung Zangbo-Mytkyina-Bago zone on the west of the South China Sea,and the Meso-Tethyan（e.g.Northern Chichibu Ocean of the Meso-Tethys）suture zone＂Butsozo tectonic line＂in the outer belt of the Jurassic-Early Cretaceous terrene group in southwest Japan,on the east of the South China Sea.

Ophiolites from the Mianlüe Suture in the Southern Qinling and Their Relationship with the Eastern Paleotethys Evolution

The Mianlue suture extends from Derni-Nanping-Pipasi-Kangxian to the Lueyang-Mianxian area, then traverses the Bashan arcuate structure eastward to the Huashan region, and finally to the Qingshuihe area of the southern Dabie Mountains. From east to west, with a length of over 1500 km, the ophiolitic melange associations are distributed discontinuously along the suture. The rock assemblages include ophiolite, island-arc and oceanic island rock series, indicating that there existed a suture zone and a vanished paleo-ocean basin. The Mianliie paleo-ocean basin experienced its main expansion and formation process during the Carboniferous-Permian and closed totally in the Triassic. It belongs to the northern branch of the eastern paleotethys, separated from the northern margin of the Yangtze block under the paleotethys mantle dynamic system.

Matched-pair analysis of postoperative morbidity and mortality for pancreaticogastrostomy and pancreaticojejunostomy using mattress sutures in soft pancreatic tissue remnants

BACKGROUND:After pancreaticoduodenectomy,the incidence of postoperative pancreatic fistula remains high,especially in patients with 'soft' pancreatic tissue remnants.No 'gold standard' surgical technique for pancreaticoenteric anastomosis has been established.This study aimed to compare the postoperative morbidity and mortality of pancreaticogastrostomy and pancreaticojejunostomy for 'soft' pancreatic tissue remnants using modified mattress sutures.METHODS:Seventy-five patients who had undergone pancreaticogastrostomy and 75 who had undergone pancreaticojejunostomy after pancreaticoduodenectomy between 2002 and 2008 were retrospectively compared using matched-pair analysis.A modified mattress suture technique was used for the pancreaticoenteric anastomosis.Patients with an underlying 'hard' pancreatic tissue remnant,as in chronic pancreatitis,were excluded.Both groups were homogeneous for age,gender,and underlying disease.Postoperative morbidity,mortality,and preoperative and operative data were analyzed.RESULTS:There were no significant differences between the groups for the incidence of postoperative pancreatic fistula (10.7% in both).Postoperative morbidity and mortality,median operation time,median length of hospital stay,intraoperative blood loss,and the amount of intraoperatively transfused erythrocyte concentrates also did not significantly differ between the groups.Patient age >65 years (P=0.017),operation time >350minutes (P=0.001),and intraoperative transfusion of erythrocyte concentrates (P=0.038) were identified as risk factors for postoperative morbidity.CONCLUSIONS:Our results showed no significant differences between the groups in the pancreaticogastrostomy and pancreaticojejunostomy anastomosis techniques using mattress sutures for 'soft' pancreatic tissue remnants.In our experience,the mattress sutures are safe and simple to use,and pancreaticogastrostomy in particular is feasible and easy to learn,with good endoscopic accessibility to the anastomosis region.However,the location of the anastomosis and the surgical technique need to be individually evaluated to further reduce the incidence of postoperative pancreatic fistula.