Unique method for removal of knotted lumbar epidural catheter: A case report

BACKGROUND Combined spinal-epidural(CSE)anesthesia is the preferred anesthesia method for cesarean delivery.The use of an epidural catheter is essential for administering additional drugs intraoperatively and managing postoperative pain.However,the insertion of epidural catheters is associated with various complications,such as total spinal anesthesia,symptoms indicative of spinal nerve root irritation,and challenges in epidural catheter removal.CASE SUMMARY We present a case report of a challenging epidural catheter removal due to knotting.The lumbar computed tomography scan results revealed that the catheter formed a tight knot in the epidural space.We used a novel extubation method and successfully removed the catheter.CONCLUSION The operator can use opposite forces to"spiral"apart the spinal joints by positioning the patient's body in a specific position.The findings indicate that,when combined with imaging examination results,this method is effective for the removal of epidural catheters.

Knowledge and practice skills on home-based urinary catheter care among parents of under-five children with urinary catheter

Objectives:The objectives of this study were to assess the knowledge and practice skills on home-based urinary catheter care among parents of under-five children with urinary catheter.Materials and Methods:This cross-sectional study was conducted from June 1,2021,to September 11,2021,in a tertiary hospital in north India.Purposive sampling was used to select 50 participants.Three instruments were employed for data collection after fulfilling sample criteria;for baseline information demographic tool,knowledge questionnaires,and a practice checklist.Data were analyzed using descriptive and inferential statistics.Results:On assessment of 50 participants,the majority of parents aged above 30 years(74%).Most of the participants were male(82%),graduated(38%),and working in the private sector(58%).Similarly,two-thirds of participants were residing in a nuclear family(64%)with a single child 32(64%)and family income<5000 rupees per month(60%).The mean score of knowledge was 1.94±0.81 and that of practice skills was 1.98±0.85 on home-based care.Regression analysis showed that knowledge of parents was significantly associated with qualification(β:1.821,P=0.002).Similarly,association of practice skills of parents with gender(β:1.235,P=0.050)and qualification(β:1.889,P=0.00)was significant.Conclusion:The general findings of our study showed that parents’education and occupation played a significant role in a child’s care.Parental education and catheter care skills positively affect the child and reduce readmission rates.

Multiple paradoxical embolisms caused by central venous catheter thrombus passing through a patent foramen ovale: A case report

BACKGROUND To date,this is the first case of a paradoxical embolism(PDE)that concurrently manifested in the coronary and lower limb arteries and was secondary to a central venous catheter(CVC)thrombus via a patent foramen ovale(PFO).CASE SUMMARY Here,we report a case of simultaneous coronary and lower limb artery embolism in a PFO patient carrier of a CVC.The patient presented to the hospital with acute chest pain and lower limb fatigue.Doppler ultrasound showed a large thrombus in the right internal jugular vein,precisely at the tip of the CVC.Transthoracic and transesophageal echocardiography confirmed the existence of a PFO,with inducible right-to-left shunting by the Valsalva maneuver.The patient was administered an extended course of anticoagulation therapy,and then the CVC was successfully removed.Percutaneous PFO closure was not undertaken.There was no recurrence during follow-up.CONCLUSION Thus,CVC-associated thrombosis is a potential source for multiple PDE in PFO patients.

Lower extremity peripherally inserted central catheter placement ectopic to the ascending lumbar vein:A case report

BACKGROUND Peripherally inserted central catheters(PICCs)are an essential infusion route for oncology patients receiving intravenous treatments,but lower extremity veni-puncture is the preferred technique for patients with superior vena cava syndrome(SVCS).We report the case of a patient with a lower extremity PICC ectopic to the ascending lumbar vein,to indicate and verify PICC catheterisation in the lower extremity is safe and feasible.And hope to provide different per-spectives for clinical PICC venipuncture to get the attention of peers.CASE SUMMARY On 24 August 2022,a 58-year-old male was admitted to our department due to an intermittent cough persisting for over a month,which worsened 10 d prior.Imaging and laboratory investigations suggested the patient with pulmonary malignancy and SVCS.Chemotherapy was not an absolute contraindication in this patient.Lower extremity venipuncture is the preferred technique because administering upper extremity venous transfusion to patients with SVCS can exacerbate oedema in the head,neck,and upper extremities.The patient and his family were informed about the procedure,and informed consent was obtained.After successful puncture and prompt treatment,the patient was discharged,experiencing some relief from symptoms.CONCLUSION Inferior vena cava catheterisation is rare and important for cancer patients with SVCS,particularly in complex situations involving ectopic placement.

Different timing for abdominal paracentesis catheter placement and drainage in severe acute pancreatitis complicated by intraabdominal fluid accumulation

BACKGROUND Non-surgical methods such as percutaneous drainage are crucial for the treatment of patients with severe acute pancreatitis(SAP).However,there is still an ongoing debate regarding the optimal timing for abdominal paracentesis catheter place-ment and drainage.AIM To explore the influence of different timing for abdominal paracentesis catheter placement and drainage in SAP complicated by intra-abdominal fluid accumu-lation.METHODS Using a retrospective approach,184 cases of SAP complicated by intra-abdominal fluid accumulation were enrolled and categorized into three groups based on the timing of catheter placement:group A(catheter placement within 2 d of symptom onset,n=89),group B(catheter placement between days 3 and 5 after symptom onset,n=55),and group C(catheter placement between days 6 and 7 after symptom onset,n=40).The differences in progression rate,mortality rate,and the number of cases with organ dysfunction were compared among the three groups.RESULTS The progression rate of group A was significantly lower than those in groups B and groups C(2.25%vs 21.82%and 32.50%,P<0.05).Further,the proportion of patients with at least one organ dysfunction in group A was significantly lower than those in groups B and groups C(41.57%vs 70.91%and 75.00%,P<0.05).The mortality rates in group A,group B,and group C were similar(P>0.05).At postoperative day 3,the levels of C-reactive protein(55.41±19.32 mg/L vs 82.25±20.41 mg/L and 88.65±19.14 mg/L,P<0.05),procalcitonin(1.36±0.51 ng/mL vs 3.20±0.97 ng/mL and 3.41±0.98 ng/mL,P<0.05),tumor necrosis factor-alpha(15.12±6.63 pg/L vs 22.26±9.96 pg/L and 23.39±9.12 pg/L,P<0.05),interleukin-6(332.14±90.16 ng/L vs 412.20±88.50 ng/L and 420.08±87.65ng/L,P<0.05),interleukin-8(415.54±68.43 ng/L vs 505.80±66.90 ng/L and 510.43±68.23ng/L,P<0.05)and serum amyloid A(270.06±78.49 mg/L vs 344.41±81.96 mg/L and 350.60±80.42 mg/L,P<0.05)were significantly lower in group A compared to those in groups B and group C.The length of hospital stay in group A was significantly lower than those in groups B and group C(24.50±4.16 d vs 35.54±6.62 d and 38.89±7.10 d,P<0.05).The hospitalization expenses in group A were also significantly lower than those in groups B and groups C[2.70(1.20,3.55)ten-thousand-yuan vs 5.50(2.98,7.12)ten-thousand-yuan and 6.00(3.10,8.05)ten-thousand-yuan,P<0.05).The incidence of complications in group A was markedly lower than that in group C(5.62%vs 25.00%,P<0.05),and similar to group B(P>0.05).CONCLUSION Percutaneous catheter drainage for the treatment of SAP complicated by intra-abdominal fluid accumulation is most effective when performed within 2 d of onset.

Computerized tomography-guided therapeutic percutaneous puncture catheter drainage-combined with somatostatin for severe acute pancreatitis: An analysis of efficacy and safety

BACKGROUND Severe acute pancreatitis(SAP),a condition with rapid onset,critical condition and unsatisfactory prognosis,poses a certain threat to human health,warranting optimization of relevant treatment plans to improve treatment efficacy.AIM To evaluate the efficacy and safety of computerized tomography-guided the-rapeutic percutaneous puncture catheter drainage(CT-TPPCD)combined with somatostatin(SS)in the treatment of SAP.METHODS Forty-two SAP patients admitted to The Second Affiliated Hospital of Fujian Medical University from June 2020 to June 2023 were selected.On the basis of routine treatment,20 patients received SS therapy(control group)and 22 patients were given CT-TPPCD plus SS intervention(research group).The efficacy,safety(pancreatic fistula,intra-abdominal hemorrhage,sepsis,and organ dysfunction syndrome),abdominal bloating and pain relief time,bowel recovery time,hospital stay,inflammatory indicators(C-reactive protein,interleukin-6,and pro-calcitonin),and Acute Physiology and Chronic Health Evaluation(APACHE)II score of both groups were evaluated for comparison.RESULTS Compared with the control group,the research group had a markedly higher total effective rate,faster abdominal bloating and pain relief and bowel recovery,INTRODUCTION Pancreatitis,an inflammatory disease occurring in the pancreatic tissue,is classified as either acute or chronic and is associated with high morbidity and mortality,imposing a socioeconomic burden[1,2].The pathogenesis of this disease involves early protease activation,activation of nuclear factor kappa-B-related inflammatory reactions,and infiltration of immune cells[3].Severe acute pancreatitis(SAP)is a serious condition involving systemic injury and subsequent possible organ failure,accounting for 20%of all acute pancreatitis cases[4].SAP is also characterized by rapid onset,critical illness and unsatisfactory prognosis and is correlated with serious adverse events such as systemic inflammatory response syn-drome and acute lung injury,threatening the health of patients[5,6].Therefore,timely and effective therapeutic inter-ventions are of great significance for improving patient prognosis and ensuring therapeutic effects.Somatostatin(SS),a peptide hormone that can be secreted by endocrine cells and the central nervous system,is in-volved in the regulatory mechanism of glucagon and insulin synthesis in the pancreas[7].It has complex and pleiotropic effects on the gastrointestinal tract,which can inhibit the release of gastrointestinal hormones and negatively modulate the exocrine function of the stomach,pancreas and bile,while exerting a certain influence on the absorption of the di-gestive system[8,9].SS has shown certain clinical effectiveness when applied to SAP patients and can regulate the severity of SAP and immune inflammatory responses,and this regulation is related to its influence on leukocyte apoptosis and adhesion[10,11].Computerized tomography-guided therapeutic percutaneous puncture catheter drainage(CT-TPPCD)is a surgical procedure to collect lesion fluid and pus samples from necrotic lesions and perform puncture and drainage by means of CT image examination and precise positioning[12].In the research of Liu et al[13],CT-TPPCD applied to pa-tients undergoing pancreatic surgery contributes to not only good curative effects but also a low surgical risk.Baudin et al[14]also reported that CT-TPPCD has a clinical success rate of 64.6%in patients with acute infectious necrotizing pan-creatitis,with nonfatal surgery-related complications found in only two cases,suggesting that this procedure is clinically effective and safe in the treatment of the disease.In light of the limited studies on the efficacy and safety of SS plus CT-TPPCD in SAP treatment,this study performed a relevant analysis to improve clinical outcomes in SAP patients.

Analysis of the Nursing Effect of Hierarchical Extended Nursing Based on The Guidance of Orem’s Theory in Patients with PICC Catheterization

Objective:To analyze the nursing effect of hierarchical extended nursing based on the guidance of Orem’s theory in patients with peripherally inserted central(PICC)catheterization.Methods:Ninety-one patients with PICC catheterization admitted to the hospital from May 2021 to May 2023 were selected and divided into a control group and an observation group,with 45 and 46 cases,respectively.The control group received routine nursing care,while the observation group received routine nursing care combined with hierarchical extended nursing based on the guidance of Orem’s theory for 3 months.Relevant indicators between the two groups were compared.Results:The improvement degree of various indicators in the observation group after nursing was better than that of the control group(P<0.05).Conclusion:Graded extended nursing based on the guidance of Orem’s theory improved the knowledge,belief,behavior,and self-efficacy of patients with PICC catheterization,and relieved their anxiety,depression,and other negative emotions.The nursing effect was deemed to be significant.

Double pigtail catheter reduction for seriously displaced intravenous infusion port catheter:A case report

BACKGROUND Implanted intravenous infusion port(TIAP)is mainly used for patients who need central venous infusion and poor peripheral vascular conditions.With the advantages of easy to carry,long maintenance cycle,few complications and excellent quality of life,it has been widely used in the fields of malignant tumor chemotherapy,parenteral nutrition support and repeated blood collection.Implanted intravenous infusion port(IVAP)dislocation can have significant complications if not recognised and reinstated immediately.CASE SUMMARY A 24-year-old man was treated with adjuvant chemotherapy for osteosarcoma.Severe displacement of IVAP catheter was found by chest X-ray examination.The IVAP cannot be used normally.Therefore,we conducted an emergency procedure to reset the catheter through double pigtail catheters,the operation was successful and the infusion port was restored.CONCLUSION When IVAP catheter displacement cannot be reset by conventional techniques,two pigtail catheters can be successfully used instead.

Controllable NO Release for Catheter Antibacteria from Nitrite Electroreduction over the Cu-MOF

Implant-associated infections caused by biomedical catheters severely threaten patients'health.The use of electrochemical control on NO release from benign nitrite equipped in the catheter can potentially resolve this issue with excellent biocompatibility.Inspired by nitrite reductase,a Cu-BDC(BDC:benzene-1,4-dicarboxylic acid)catalyst with coordinated Cu(Ⅱ)sites was constructed as a heterogeneous electrocatalyst to control nitrite reduction to nitric oxide for catheter antibacteria.The combined results of in situ and ex situ tests unveil the key function of interconversion between Cu(Ⅱ)and Cu(Ⅰ)species in NO_(2)^(-)reduction to NO.After being incorporated into the actual catheter,the Cu-BDC catalyst exhibits high electrocatalytic activity toward NO_(2)^(-)reduction to NO and excellent antibacteria efficacy with a sterilizing rate of 99.9%,paving the way for the development of advanced metal-organic frameworks(MOFs)electrocatalysts for catheter antibacteria.

Transseptal approach for catheter ablation of left-sided accessory pathways in children with Marfan syndrome:A case report

BACKGROUND Left-sided accessory pathways(APs)can be accessed with either a transaortic(TA)or transseptal approach(TS).For children with Marfan syndrome(MFS)who have aortic disease,the use of TA can aggravate the disease,making TS the best choice for these patients.CASE SUMMARY A 10-year-old girl was hospitalized because of intermittent heart palpitations and chest tightness.She was diagnosed with MFS,supraventricular tachycardia,Wolff-Parkinson-White syndrome,and left-sided AP was detected by cardiac electrophysiological.Catheter ablation was successfully performed via TS under the guidance of the Ensite system.During the follow-up,no recurrence or complications occurred.CONCLUSION The TS for catheter ablation of left-sided APs can be considered in children with MFS.Adequate evaluation and selection of the appropriate puncture site are particularly important.

The Application of Midline Catheter in Perioperative Period of Patients with Laryngopharyngeal Cancer

Objective: To investigate the application value of midline catheters in patients with larynx cancer during the postoperative period. Methods: 150 patients with larynx cancer treated in our hospital from May 2019 to May 2022 were selected as the study objects. According to the random number method, 75 cases were divided into a control group and a study group. The study group used a midline catheter during treatment, and the control group used a Peripheral venous indwelling needle during treatment. The indwelling time, puncture times, complication rate, daily catheter maintenance cost and catheterization satisfaction rate of the two groups were compared. Result: The retention time of the study group (11.53 ± 6.91 days) was significantly higher than that of the control group (2.92 ± 1.41 days) (P . The total puncture times were significantly lower than that of the control group (P cidence of complications such as catheter blockage, catheter detachment, drug extravasation and phlebitis were lower than those of the control group. The difference was statistically significant (P < 0.05), the average daily maintenance cost of the two groups was not statistically significant (P > 0.05), and the satisfaction rate of the study group was significantly higher than that of the control group, the difference was statistically significant (P Conclusion: Compared with the Peripheral venous indwelling needle, postoperative application of a midline catheter in patients with larynx cancer can effectively reduce the number of puncture times and the incidence of catheter-related adverse reactions, and has higher economic benefits and satisfaction rate, which is worthy of clinical application.

“Guidezilla”extension catheter combined with balloon technique for treating pulmonary artery stenosis caused by Takayasu arteritis

Takayasu arteritis(TA)is a rare systemic vasculitis of the aorta and its primary branches,which usually occurs in young women.Due to its insidious onset and lack of specific symptoms,this disease can be easily misdiagnosed or missed.Approximately 50%of the patients having TA with pulmonary artery involvement develop pulmonary hypertension(PH).The 3-year survival rate among patients with TA-related PH is lower than that among patients with TA alone.Early balloon pulmonary angioplasty(BPA)can improve the clinical symptoms and survival of patients with stable TA.To the best of our knowledge,this is the first case reported in the English literature in which a“Guidezilla”catheter was used during BPA to treat stenosis and occlusion of the pulmonary artery caused by Takayasu arteritis(TA).

Central venous catheterization-related complications in a cohort of 100 hospitalized patients:An observational study

Objective:To evaluate the complications of central venous catheterization(CVC).Methods:A prospective,observational study was conducted at a tertiary care center in India from December 2018 to September 2020.Critically ill patients(aged≥18 years)in the intensive care unit undergoing CVC procedures were included in the study.Baseline demographics and detailed medical history were recorded.Chest X-rays and electrocardiography were performed on all the patients.Complications associated with CVC were recorded.Results:A total of 100 patients with the indication for central venous catheter insertion were included.The majority(81%)of the patients were inserted with CVC at the right internal jugular vein.Complications such as arterial puncture(2%),hematoma(4%),blood clot formation(4%),catheter kinking(3%),thoracic injury(1%),thrombophlebitis(6%),sepsis(9%)and nerve injury(1%)were reported.Conclusions:Though central venous access is preferred in management of critically ill patients,it has its risks.However,early recognition and prompt management of complications may reduce mortality and morbidity.Physicians and intensive care unit intensivists should be vigilant for central venous catheter-related complications.Suitable site selection,operator experience,and proper catheter maintenance are associated with optimal outcomes.

Effectiveness and Safety of Transcatheter Closure of Various Ventricular Septal Defects Using Second-Generation Amplatzer Duct Occluders

Objective:This study was designed to determine the long-term safety and efficacy of using the Amplatzer Duct Occluder II(ADO II)for the closure of various ventricular septal defects(VSDs).Methods:From January 2011 to December 2019,selected VSD patients were treated through transcatheter intervention using ADO II occluders.The closure results and complications from 188 patients,involving 167 perimembranous ventricular septal defects(pmVSDs),9 intracristal VSDs,11 post surgery residual shunts and 1 post closure residual shunt with the mean outlet diameter3.1±0.8 mm under angiography,were enrolled in this study.Results:The success rate was 98.9%for all procedures.During the median 77-month follow-up period,no cases of complete atrioventricular block(cAVB),infective endocarditis or death occurred.One major adverse event(0.5%)was recorded:cerebrovascular accident occurred 1 day after the procedure in one patient who was transferred to the neurology department.The residual shunt rate was 44.6%,which was the most common minor adverse event.The cardiac conduction block rate was 4.3%.Specifically,one pmVSD patient developed intermittent LBBB during the 28-month follow-up.There were 3 patients(1.6%)with new-onset mild tricuspid insufficiency,and the insufficiency degree was stable during follow-up.There was no new-onset aortic insufficiency that occurred.Conclusions:Transcatheter closure of pmVSDs,some intracristal VSDs,some postsurgery or postclosure residual shunts using ADO II occluders were both safe and effective and yielded excellent long-term results in selected patients.

Emphysematous thrombophlebitis caused by a misplaced central venous catheter: A case report

BACKGROUND Central venous catheters(CVCs)often cause life-threatening complications,especially CVC-related bloodstream infection(CVC-BSI)and catheter-related thrombosis(CRT).Here,we report an unusual case of misplaced CVC-induced emphysematous thrombophlebitis,a rare but potentially lethal form of CRT and CVC-BSI characterized by both thrombosis and gas formation.CASE SUMMARY A 48-year-old male presented to the emergency room of a local hospital with sudden-onset headache and coma for 4 h.Computed tomography(CT)revealed right basal ganglia hemorrhage,so emergency decompressive craniotomy was performed and a CVC was inserted through the right subclavian vein for fluid resuscitation during anesthesia.Two days later,the patient was transferred to the intensive care unit of our hospital for further critical care.On day 9 after CVC insertion,the patient suddenly developed fever and hypotension.Point-of-care ultrasound(POCUS)demonstrated thrombosis and dilatation of the right internal jugular vein(IJV)filled with thrombosis.Ultrasonography also revealed that the CVC tip had been misplaced into the IJV and was surrounded by gas bubbles,which manifested as hyperechoic lines with dirty shadowing and comet-tail artifacts.Further CT scan confirmed air bubbles surrounding the CVC in the right neck.The final diagnosis was septic emphysematous thrombophlebitis induced by a misplaced CVC and ensuing septic shock.The responsible CVC was removed immediately.The patient received fluid resuscitation,intravenous noradrenaline,and a 10-d ultra-broad spectrum antibiotic treatment to combat septic shock.Both CVC and peripheral venous blood cultures yielded methicillin-resistant Staphylococcus cohnii.The patient was gradually weaned off vasopressors and the symptoms of redness and swelling in the right neck subsided within 7 d.CONCLUSION Emphysematous thrombophlebitis is a fulminant and life-threatening CVC-BSI associated with thrombosis and gas formation in the vein.A misplaced CVC may facilitate the development of emphysematous thrombophlebitis.POCUS can easily identify the artifacts produced by gas and thrombosis,facilitating rapid diagnosis at the bedside.

Long-term results of single-procedure catheter ablation for atrial fibrillationin pre-and post-menopausal women

ObjectivesTo 地址经绝期是否由比较安全和长期的结果为 atrial 纤维性颤动(AF ) 影响导管脱离(CA ) 的结果一在经历了药倔强的 AF 的一个单个 CA 过程的 743 个女病人全部的绝经前、绝经后的 women.MethodsA 单个过程回顾地被分析。在为在绝经前的女人之间的 AF 的 CA 的临床的表示和结果的差别(PreM 组， 94 个病人， 12.7%) 并且绝经后的女人(PostM 组， 649 个病人， 87.3%) 在 PreM 组的 assessed.ResultsThe 病人更年轻(P &#x0003c；0.001 ) 并且不太可能有高血压(P &#x0003c；0.001 ) 并且糖尿病(P = 0.005 ) 比那些在 PostM 组。二个组关于伴随物的比例是类似的僧帽形的阀门流回冠的动脉疾病，左中庭尺寸，和左室的喷射部分。与 AF 脱离有关的复杂并发症的全面的率在两个组是类似的(P = 0.385 ) 。在 43 以后(16-108 ) 后续的月，脱离的成功率在 PreM 组是 54.3% ， 54.2% 在 PostM 组织(P = 0.842 ) 。从 atrial tachyarrhythmia 复发的全面自由在两个组是类似的。经绝期没被发现是为 AF 的单个过程的 CA 的长期的结果是的 atrial tachyarrhythmia.ConclusionsThe 的复发的一个独立预兆的因素在绝经前、绝经后的女人类似。结果显示 AF 的 CA 看起来在绝经前的女人同样象在绝经后的女人安全、有效。

Development and validation of a risk prediction model for repeated indwelling urinary catheterization in patients with cervical cancer after surgery

Objective:To study the factors influencing secondary indwelling catheterisation after cervical cancer surgery and to develop a predictive risk model.Methods:A total of 260 patients in a tertiary hospital in Chongqing were selected from January 2020 to December 2021 via convenience sampling.Relevant information of patients was recorded,including age;body mass index;history of hypertension and diabetes,bladder dysfunction,postoperative urinary retention,and postoperative urinary tract infection;Histology;staging;surgical approach;Operation time;Time of first remove of catheter;indwelling catheter days;Hospitalization days.Least absolute shrinkage and selection operator was used to reduce dimensionality and select patient characteristics,and multivariate analysis was performed based on the selected variables.Based on the outcome of analysis,a line chart model was developed for predicting the risk of secondary catheterization in patients with indwelling catheterization after radical cervical cancer surgery.The coefficient of conformity index(C-index)and calibration curves were used to evaluate the accuracy and fit.The model was internally validated via bootstrapping(1000 random samples),and the clinical utility of the model was assessed via decision curve analysis(DCA).Results:Four characteristic variables were selected,including preoperative bladder function,postoperative urinary tract infection,surgical approach,and Time of first remove of catheter.They are independent risk factors affecting urinary tract.The risk prediction model exhibited good discrimination performance with a C-index of 0.722(95%CI,0.661-0.783)and was well calibrated.The C-index was 0.708 in internal validation analysis.DCA showed that the risk model was clinically useful for predicting secondary catheterization,and clinical benefits were observed at the decision threshold of≥11%.Conclusion:A novel model was developed to predict the risk of secondary catheterization.The model was based on preoperative bladder dysfunction,postoperative urinary tract infection,surgical approach,and number of days since the removal of the primary catheter.

Long-Term Performance and Microstructural Characterization of Dam Concrete in the Three Gorges Project

This study investigates the long-term performance of laboratory dam concrete in different curing environments over ten years and the microstructure of 17-year-old laboratory concrete and actual concrete cores drilled from the Three Gorges Dam.The mechanical properties of the laboratory dam concrete,whether cured in natural or standard environments,continued to improve over time.Furthermore,the laboratory dam concrete exhibited good resistance to diffusion and a refined microstructure after 17 years.However,curing and long-term exposure to the local natural environment reduced the frost resistance.Microstructural analyses of the laboratory concrete samples demonstrated that moderate-heat cement and fine fly ash(FA)particles were almost fully hydrated to form compact micro structures consisting of large quantities of homogeneous calcium(alumino)silicate hydrate(C-(A)-S-H)gels and a few crystals.No obvious interfacial transition zones were observed in the microstructure owing to the longterm pozzolanic reaction.This dense and homogenous microstructure was the crucial reason for the excellent long-term performance of the dam concrete.A high FA volume also played a significant role in the microstructural densification and performance growth of dam concrete at a later age.The concrete drilled from the dam surface exhibited a loose microstructure with higher microporosity,indicating that concrete directly exposed to the actual service environment suffered degradation caused by water and wind attacks.In this study,both macro-performance and microstructural analyses revealed that the application of moderate-heat cement and FA resulted in a dense and homogenous microstructure,which ensured the excellent long-term performance of concrete from the Three Gorges Dam after 17 years.Long-term exposure to an actual service environment may lead to microstructural degradation of the concrete surface.Therefore,the retained long-term dam concrete samples need to be further researched to better understand its microstructural evolution and development of its properties.

Soil bacterial and fungal communities resilience to long-term nitrogen addition in subtropical forests in China

Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in China.The four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence networks.Nutrient-treated soils were more acidic and had higher levels of dissolved organic carbon than controls.There were no significant differences in microbial diversity and community composition across treatments.The addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network connectivity.Three rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased nutrients.The results indicate that the overall composition of microbial communities was stable but not static to long-term N addition.Our findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition.

Clinical manifestations,diagnosis and long-term prognosis of adult autoimmune enteropathy:Experience from Peking Union Medical College Hospital

BACKGROUND Autoimmune enteropathy(AIE)is a rare disease whose diagnosis and long-term prognosis remain challenging,especially for adult AIE patients.AIM To improve overall understanding of this disease’s diagnosis and prognosis.METHODS We retrospectively analyzed the clinical,endoscopic and histopathological characteristics and prognoses of 16 adult AIE patients in our tertiary medical center between 2011 and 2023,whose diagnosis was based on the 2007 diagnostic criteria.RESULTS Diarrhea in AIE patients was characterized by secretory diarrhea.The common endoscopic manifestations were edema,villous blunting and mucosal hyperemia in the duodenum and ileum.Villous blunting(100%),deep crypt lymphocytic infiltration(67%),apoptotic bodies(50%),and mild intraepithelial lymphocytosis(69%)were observed in the duodenal biopsies.Moreover,there were other remarkable abnormalities,including reduced or absent goblet cells(duodenum 94%,ileum 62%),reduced or absent Paneth cells(duodenum 94%,ileum 69%)and neutrophil infiltration(duodenum 100%,ileum 69%).Our patients also fulfilled the 2018 diagnostic criteria but did not match the 2022 diagnostic criteria due to undetectable anti-enterocyte antibodies.All patients received glucocorticoid therapy as the initial medication,of which 14/16 patients achieved a clinical response in 5(IQR:3-20)days.Immunosuppressants were administered to 9 patients with indications of steroid dependence(6/9),steroid refractory status(2/9),or intensified maintenance medication(1/9).During the median of 20.5 months of followup,2 patients died from multiple organ failure,and 1 was diagnosed with non-Hodgkin’s lymphoma.The cumulative relapse-free survival rates were 62.5%,55.6%and 37.0%at 6 months,12 months and 48 months,respectively.CONCLUSION Certain histopathological findings,including a decrease or disappearance of goblet and Paneth cells in intestinal biopsies,might be potential diagnostic criteria for adult AIE.The long-term prognosis is still unsatisfactory despite corticosteroid and immunosuppressant medications,which highlights the need for early diagnosis and novel medications.