Ileal-anal pouches: A review of its history, indications, and complications

The ileal pouch anal anastomosis(IPAA)has revolutionised the surgical management of ulcerative colitis(UC)and familial adenomatous polyposis(FAP).Despite refinement in surgical technique(s)and patient selection,IPAA can be associated with significant morbidity.As the IPAA celebrated its 40th anniversary in 2018,this review provides a timely outline of its history,indications,and complications.IPAA has undergone significant modification since 1978.For both UC and FAP,IPAA surgery aims to definitively cure disease and prevent malignant degeneration,while providing adequate continence and avoiding a permanent stoma.The majority of patients experience long-term success,but“early”and“late”complications are recognised.Pelvic sepsis is a common early complication with far-reaching consequences of long-term pouch dysfunction,but prompt intervention(either radiological or surgical)reduces the risk of pouch failure.Even in the absence of sepsis,pouch dysfunction is a longterm complication that may have a myriad of causes.Pouchitis is a common cause that remains incompletely understood and difficult to manage at times.10%of patients succumb to the diagnosis of pouch failure,which is traditionally associated with the need for pouch excision.This review provides a timely outline of the history,indications,and complications associated with IPAA.Patient selection remains key,and contraindications exist for this surgery.A structured management plan is vital to the successful management of complications following pouch surgery.

Revealing the Multifunctional Electrocatalysis of Indium-Modulated Phthalocyanine for High-Performance Lithium-Sulfur Batteries

The sluggish kinetics of complicated multiphase conversions and the severe shuttling effect of lithium polysulfides(LiPSs)significantly hinder the applications of Li-S battery,which is one of the most promising candidates for the next-generation energy storage system.Herein,a bifunctional electrocatalyst,indium phthalocyanine self-assembled with carbon nanotubes(InPc@CNT)composite material,is proposed to promote the conversion kinetics of both reduction and oxidation processes,demonstrating a bidirectional catalytic effect on both nucleation and dissolution of Li_(2)S species.The theoretical calculation shows that the unique electronic configuration of InPc@CNT is conducive to trapping soluble polysulfides in the reduction process,as well as the modulation of electron transfer dynamics also endows the dissolution of Li_(2)S in the oxidation reaction,which will accelerate the effectiveness of catalytic conversion and facilitate sulfur utilization.Moreover,the InPc@CNT modified separator displays lower overpotential for polysulfide transformation,alleviating polarization of electrode during cycling.The integrated spectroscopy analysis,HRTEM,and electrochemical study reveal that the InPc@CNT acts as an efficient multifunctional catalytic center to satisfy the requirements of accelerating charging and discharging processes.Therefore,the Li-S battery with InPc@CNT-modified separator obtains a discharge-specific capacity of 1415 mAh g^(-1)at a high rate of 0.5 C.Additionally,the 2 Ah Li-S pouch cells deliver 315 Wh kg^(-1)and achieved 80%capacity retention after 50 cycles at 0.1 C with a high sulfur loading of 10 mg cm^(-2).Our study provides a practical method to introduce bifunctional electrocatalysts for boosting the electrochemical properties of Li-S batteries.

Mitigated reaction kinetics between lithium metal anodes and electrolytes by alloying lithium metal with low-content magnesium

Lithium(Li)metal is regarded as a promising anode candidate for high-energy-density rechargeable batteries.Nevertheless,Li metal is highly reactive against electrolytes,leading to rapid decay of active Li metal reservoir.Here,alloying Li metal with low-content magnesium(Mg)is proposed to mitigate the reaction kinetics between Li metal anodes and electrolytes.Mg atoms enter the lattice of Li atoms,forming solid solution due to the low amount(5 wt%)of Mg.Mg atoms mainly concentrate near the surface of Mg-alloyed Li metal anodes.The reactivity of Mg-alloyed Li metal is mitigated kinetically,which results from the electron transfer from Li to Mg atoms due to the electronegativity difference.Based on quantitative experimental analysis,the consumption rate of active Li and electrolytes is decreased by using Mgalloyed Li metal anodes,which increases the cycle life of Li metal batteries under demanding conditions.Further,a pouch cell(1.25 Ah)with Mg-alloyed Li metal anodes delivers an energy density of 340 Wh kg^(-1)and a cycle life of 100 cycles.This work inspires the strategy of modifying Li metal anodes to kinetically mitigate the side reactions with electrolytes.

Boosting High-Voltage Practical Lithium Metal Batteries with Tailored Additives

The lithium(Li)metal anode is widely regarded as an ideal anode material for high-energy-density batteries.However,uncontrolled Li dendrite growth often leads to unfavorable interfaces and low Coulombic efficiency(CE),limiting its broader application.Herein,an ether-based electrolyte(termed FGN-182)is formulated,exhibiting ultra-stable Li metal anodes through the incorporation of LiFSI and LiNO3 as dual salts.The synergistic effect of the dual salts facilitates the formation of a highly robust SEI film with fast Li+transport kinetics.Notably,Li||Cu half cells exhibit an average CE reaching up to 99.56%.In particular,pouch cells equipped with high-loading lithium cobalt oxide(LCO,3 mAh cm^(-2))cathodes,ultrathin Li chips(25μm),and lean electrolytes(5 g Ah-1)demonstrate outstanding cycling performance,retaining 80%capacity after 125 cycles.To address the gas issue in the cathode under high voltage,cathode additives 1,3,6-tricyanohexane is incorporated with FGN-182;the resulting high-voltage LCO||Li(4.4 V)pouch cells can cycle steadily over 93 cycles.This study demonstrates that,even with the use of ether-based electrolytes,it is possible to simultaneously achieve significant improvements in both high Li utilization and electrolyte tolerance to high voltage by exploring appropriate functional additives for both the cathode and anode.

Analysis of Differences in Electrochemical Performance Between Coin and Pouch Cells for Lithium-Ion Battery Applications

Small coin cell batteries are predominantly used for testing lithium-ion batteries(LIBs)in academia because they require small amounts of material and are easy to assemble.However,insufficient attention is given to difference in cell performance that arises from the differences in format between coin cells used by academic researchers and pouch or cylindrical cells which are used in industry.In this article,we compare coin cells and pouch cells of different size with exactly the same electrode materials,electrolyte,and electrochemical conditions.We show the battery impedance changes substantially depending on the cell format using techniques including Electrochemical Impedance Spectroscopy(EIS)and Galvanostatic Intermittent Titration Technique(GITT).Using full cell NCA-graphite LIBs,we demonstrate that this difference in impedance has important knock-on effects on the battery rate performance due to ohmic polarization and the battery life time due to Li metal plating on the anode.We hope this work will help researchers getting a better idea of how small coin cell formats impact the cell performance and help predicting improvements that can be achieved by implementing larger cell formats.

12.6μm-Thick Asymmetric Composite Electrolyte with Superior Interfacial Stability for Solid-State Lithium-Metal Batteries

Solid-state lithium metal batteries(SSLMBs)show great promise in terms of high-energy-density and high-safety performance.However,there is an urgent need to address the compatibility of electrolytes with high-voltage cathodes/Li anodes,and to minimize the electrolyte thickness to achieve highenergy-density of SSLMBs.Herein,we develop an ultrathin(12.6μm)asymmetric composite solid-state electrolyte with ultralight areal density(1.69 mg cm^(−2))for SSLMBs.The electrolyte combining a garnet(LLZO)layer and a metal organic framework(MOF)layer,which are fabricated on both sides of the polyethylene(PE)separator separately by tape casting.The PE separator endows the electrolyte with flexibility and excellent mechanical properties.The LLZO layer on the cathode side ensures high chemical stability at high voltage.The MOF layer on the anode side achieves a stable electric field and uniform Li flux,thus promoting uniform Li^(+)deposition.Thanks to the well-designed structure,the Li symmetric battery exhibits an ultralong cycle life(5000 h),and high-voltage SSLMBs achieve stable cycle performance.The assembled pouch cells provided a gravimetric/volume energy density of 344.0 Wh kg^(−1)/773.1 Wh L^(−1).This simple operation allows for large-scale preparation,and the design concept of ultrathin asymmetric structure also reveals the future development direction of SSLMBs.

Unraveling high efficiency multi-step sodium storage and bidirectional redox kinetics synergy mechanism of cobalt-doping vanadium disulfide anode

Sodium-based storage devices based on conversion-type metal sulfide anodes have attracted great atten-tion due to their multivalent ion redox reaction ability.However,they also suffer from sodium polysul-fides(NaPSs)shuttling problems during the sluggish Na^(+) redox process,leading to"voltage failure"and rapid capacity decay.Herein,a metal cobalt-doping vanadium disulfide(Co-VS_(2))is proposed to simulta-neously accelerate the electrochemical reaction of VS_(2) and enhance the bidirectional redox of soluble NaPSs.It is found that the strong adsorption of NaPSs by V-Co alloy nanoparticles formed in situ during the conversion reaction of Co-VS_(2) can effectively inhibit the dissolution and shuttle of NaPSs,and ther-modynamically reduce the formation energy barrier of the reaction path to effectively drive the complete conversion reaction,while the metal transition of Co elements enhances reconversion kinetics to achieve high reversibility.Moreover,Co-VS_(2) also produce abundant sulfur vacancies and unsaturated sulfur edge defects,significantly improve ionic/electron diffusion kinetics.Therefore,the Co-VS_(2) anode exhibits ultrahigh rate capability(562 mA h g^(-1) at 5 A g^(-1)),high initial coulombic efficiency(~90%)and 12,000 ultralong cycle life with capacity retention of 90%in sodium-ion batteries(SIBs),as well as impressive energy/power density(118 Wh kg^(-1)/31,250 W kg^(-1))and over 10.000 stable cycles in sodium-ion hybrid capacitors(SIHCs).Moreover,the pouch cell-type SIHC displays a high-energy density of 102 Wh kg^(-1) and exceed 600 stable cycles.This work deepens the understanding of the electrochemical reaction mechanism of conversion-type metal sulfide anodes and provides a valuable solution to the shuttlingofNaPSs inSIBsandSIHCs.

Fecal microbiota transplantation for Clostridium difficile infection in patients with ileal pouches

Background:Clostridium difficile infection(CDI)in patients with ileal pouch-anal anastomosis(IPAA)has been increasingly recognized.The aim of this study was to evaluate the outcome of fecal microbiota transplantation(FMT)in patients with pouch and CDI.Methods:All consecutive patients that underwent FMT for CDI from 2012 to 2016 were extracted from our IRB-approved,prospectively maintained Registry of Pouch Disorders.The primary outcome was negative stool tests for Clostridium difficile after FMT and the secondary outcomes were symptomatic and endoscopic responses.Results:A total of 13 patients were included in this study,with 10 being Caucasian males(76.9%).All patients had underlying ulcerative colitis for J pouch surgery.After a mean of 2.8±0.8 courses of antibiotic treatments was given and failed,22 sessions of FMT were administered with an average of 1.7±1.1 sessions each.Within the 22 sessions,16 were given via pouchoscopy,4 via esophagogastroduodenoscopy and 2 via enemas.All patients tested negative on C.difficile polymerase chain reaction(PCR)after the initial FMT with a total of 7/12(58.3%)documented patients showed symptomatic improvements and 3/11(27.3%)patients showed endoscopic improvement according to the modified Pouchitis Disease Activity Index.During the follow-up of 1.2±1.1 years,there were a total of five patients(38.5%)that had recurrence after the successful initial treatment and four of them were successfully treated again with FMT.Conclusions:FMT appeared to be effective in eradication of CDI in patients with ileal pouches.However,FMT had a modest impact on endoscopic inflammation and recurrence after FMT and recurrence was common.

PDGF signaling from pharyngeal pouches promotes arch artery morphogenesis

The great vessels of the heart originate from the pharyngeal arch arteries(PAAs).Anomalies of the PAAs often occur together with pharyngeal pouch malfo rmations,but the reasons for this phenomenon are not fully understood.In the current study,we show that platelet-derived growth factor(PDGF)signaling derived from the pharyngeal pouches plays an important function in PAA vasculogenesis,During PAA development in zebrafish embryos,pdgfaa and pdgfab are expressed in the developing pharyngeal pouches.Results from loss-of-function experiments revealed a critical role of these genes in PAA formation.We found that nitroreductase(NTR)-mediated pouch ablation distinctly decreased PDGF receptor tyrosine phosphorylation,yielding a severe loss of PAAs.Importantly,pouch-specific overexpression of pdgfaa in pdgfaa-/-;pdgfab-/-mutants significantly relieved the PAA defects,which indicated a primary role of pharyngeal pouch-expressed PDGF ligands in signal activation and PAA morphogenesis.Our findings further showed that PDGF signaling was indispensable for the proliferation of PAA angioblasts.Together,these results established a role for PDGFaa-and PDGFab-mediated tissuetissue interaction during PAA development.

Value of routine stool testing for pathogenic bacteria in the evaluation of symptomatic patients with ileal pouches

Background:In symptomatic patients with an ileal pouch,stool studies are often sent to diagnose enteric pathogens.Aim of this study is to find the value of routine stool studies in the evaluation of symptomatic patients and the clinical implications of such pathogens in patients with ileal pouches.Methods:Consecutive ileal pouch-anal anastomosis(IPAA)patients who had stool tests out of a 2283-case registry from 2002 to 2015 were included in the study.Patients with positive stool cultures were compared with controls(symptomatic without positive stool culture)in a 1:4 ratio.Response to antibiotic therapy,recurrence rate and rate of hospitalization at 1 and 3 months were assessed.Results:A total of 643(28%)had stool cultures done and only 1.7%(11/643)were found to be positive for stool cultures.Campylobacter spp.(45%)was the most common pathogen followed by Aeromonas spp.(36%).Non-smokers and patients without any antibiotic use in the last 3 months were found to have higher prevalence of positive stool cultures than controls(p<0.001 and p¼0.023).Patients with pathogenic bacteria were found to have a higher risk of acute kidney injury(27.3%vs 4.5%,p¼0.049),hospitalization within 3 months of initial stool testing(36.4%vs 6.8%,p¼0.009)and mortality(18.2%vs 0%,p¼0.040).However,there were no statistically significant differences in the clinical outcomes in patients with positive stool cultures who received pathogen-directed therapy.Conclusions:We found that the yield of stool tests for bacterial pathogens in symptomatic pouch patients was extremely low and the treatment of detected pathogens had a minimum impact on the disease course of pouchitis.The clinical utility of routine stool culture in those patients warrants further study.

Constructing a 700 Wh kg^(-1)-level rechargeable lithium-sulfur pouch cell

Lithium–sulfur(Li–S)batteries are considered as highly promising energy storage devices because of their ultrahigh theoretical energy density of 2600 Wh kg^(-1).The highest practical energy density of Li–S batteries reported at pouch cell level has exceeded 500 Wh kg^(-1),which significantly surpasses that of lithium-ion batteries.Herein,a 700 Wh kg^(-1)-level Li–S pouch cell is successfully constructed.The pouch cell is designed at 6 Ah level with high-sulfur-loading cathodes of 7.4 mgScm^(-2),limited anode excess(50μm in thickness),and lean electrolyte(electrolyte to sulfur ratio of 1.7 gelectrolyteg^(-1)S).Accordingly,an ultrahigh specific capacity of 1563 m A h g^(-1)is achieved with the addition of a redox comediator to afford a practical energy density of 695 Wh kg^(-1)based on the total mass of all components.The pouch cell can operate stably for three cycles and then failed due to rapidly increased polarization at the second discharge plateau.According to failure analysis,electrolyte exhaustion is suggested as the key limiting factor.This work achieves a significant breakthrough in constructing high-energy-density Li–S batteries and propels the development of Li–S batteries toward practical working conditions.

Highly soluble organic nitrate additives for practical lithium metal batteries

The stability of lithium metal anodes essentially dictates the lifespan of high-energy-density lithium metal batteries.Lithium nitrate(LiNO_(3))is widely recognized as an effective additive to stabilize lithium metal anodes by forming LiN_(x)O_(y)-containing solid electrolyte interphase(SEI).However,its poor solubility in electrolytes,especially ester electrolytes,hinders its applications in lithium metal batteries.Herein,an organic nitrate,isosorbide nitrate(ISDN),is proposed to replace LiNO_(3).ISDNhas a high solubility of 3.3M in ester electrolytes due to the introduction of organic segments in the molecule.The decomposition of ISDN generates LiN_(x)O_(y)-rich SEI,enabling uniform lithium deposition.The lifespan of lithium metal batteries with ISDN significantly increases from 80 to 155 cycles under demanding conditions.Furthermore,a lithium metal pouch cell of 439Whkg^(−1) delivers 50 cycles.This work opens a new avenue to develop additives by molecular modifications for practical lithium metal batteries.

Lithium plating-free 1 Ah-level high-voltage lithium-ion pouch battery via ambi-functional pentaerythritol disulfate

Elevating the charge cut-off voltage beyond traditional 4.2 V is a commonly accepted technology to increase the energy density of Li-ion batteries(LIBs) but the risk of Li-dendrites and fire hazard increases as well. The use of ambi-functional additive, which forms stable solid electrolyte interphase(SEI) simultaneously at both cathode and anode, is a key to enabling a dendrites-free and well-working high-voltage LIB. Herein, a novel ambi-functional additive, pentaerythritol disulfate(PEDS), at 1 wt% without any other additive is demonstrated. We show the feasibility and high impacts of PEDS in forming lithium sulfateincorporated robust SEI layers at NCM523 cathode and graphite anode in 1 Ah-level pouch cell under4.4 V, 25 °C and 0.1 C rate, which mitigates the high-voltage instability, metal-dissolution and cracks on NCM523 particles, and prevents Li-dendrites at graphite anode. Improved capacity retention of 83%after 300 cycles is thereby achieved, with respect to 69% with base electrolyte, offering a promising path toward the design of practical high-energy LIBs.

Outstanding performances of graphite||NMC622 pouch cells enabled by a non-inert diluent

Although high salt concentration electrolyte(HCE)can construct effective Li F-rich interphase film and solve the interphasial instability issue of graphite anode,its high cost,high viscosity and poor wettability with electrode materials limit its large-scale application.Generally,localized high concentration electrolyte(LHCE)is obtained by introducing an electrochemically inert diluent into HCE to avoid the above-mentioned problems while maintaining the high interphasial stability of HCE with graphite anode.Unlike traditional inert diluents,1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluropropyl ether(TTE)with electrochemical activity is introduced into propylene carbonate(PC)-based HCE to obtain LHCE-2(1 M LiPF_(6),PC:DMC:TTE=1:1:6.1)herein.Experimental and theoretical simulation results show that TTE participates in the oxidation decomposition and film-forming reaction at the NCM622 cathode surface,conducting a cathode electrolyte interphase(CEI)rich in organic fluorides with excellent electron insulation ability,high structural stability and low interphasial impedance.Thanks to the outstanding interphasial properties induced by LHCE-2,the graphite||NMC622 pouch cell reaches a capacity retention of 80%after 500 cycles at 1 C under room temperature.While at sub-zero temperatures,the capacity released by the cell with LHCE-2 electrolyte is significantly higher than that of HCE and conventional EC-based electrolytes.Meanwhile,the LHCE-2 electrolyte inherits the advantages of TTE flame-resistant,thus improving the safety of the battery.

High-Performance Quasi-Solid-State Pouch Cells Enabled by in situ Solidification of a Novel Polymer Electrolyte

Conventional lithium-ion batteries(LIBs)with liquid electrolytes are challenged by their big safety concerns,particularly used in electric vehicles.All-solid-state batteries using solid-state electrolytes have been proposed to significantly improve safety yet are impeded by poor interfacial solid–solid contact and fast interface degradation.As a compromising strategy,in situ solidification has been proposed in recent years to fabricate quasi-solid-state batteries,which have great advantages in constructing intimate interfaces and cost-effective mass manufacturing.In this work,quasi-solid-state pouch cells with high loading electrodes(≥3 m Ah cm^(-2))were fabricated via in situ solidification of poly(ethylene glycol)diacrylate-based polymer electrolytes(PEGDA-PEs).Both single-layer and multilayer quasi-solid-state pouch cells(2.0 Ah)have demonstrated stable electrochemical performance over500 cycles.The superb electrochemical stability is closely related to the formation of robust and compatible interphase,which successfully inhibits interfacial side reactions and prevents interfacial structural degradation.This work demonstrates that in situ solidification is a facile and cost-effective approach to fabricate quasi-solid-state pouch cells with both excellent electrochemical performance and safety.

Full-chain enhanced ion transport toward stable lithium metal anodes

The dendrite growth that results from the slow electrode process kinetics prevents the lithium(Li) metal anode from being used in practical applications. Here, full-chain enhanced ion transport for stabilizing Li metal anodes is proposed. Experimental and theoretical studies confirm that full-chain enhanced ion transport(electrocrystallization, mass transport in the electrolyte and diffusion in solid electrolyte interphase) under magnetoelectrochemistry contributes to a homogeneous, dense, and dendrite-free morphology. Specifically, the enhanced electrocrystallization behavior promotes the Li nucleation;the enhanced mass transport in the electrolyte alleviates the ion concentration gradient at the electrode surface, which helps to inhibit dendrite growth;and the enhanced diffusion in the solid electrolyte interphase further homogenizes the Li deposition behavior, obtaining regular and uniform Li particles.Consequently, the Li metal anode has exceptional cycling stability in both symmetric and full cells,and the pouch cell performs long cycles(170 cycles) in practice evaluation. This work advances fundamental knowledge of the magneto-dendrite effect and offers a new perspective on stabilizing metal anodes.

Tracking gassing behavior in pouch cell by operando on-line electrochemical mass spectrometry

As the rapid development of more powerful and safer lithiumion batteries, the mechanism study of gases evolution is attacking more and more attention in recent years. Especially under overcharge/discharge and/or high-temperature working condition.

Uncovering the degradation mechanism induced by ion-diffusion kinetics in large-format lithium-ion pouch cells

Battery electrochemistry in an actual cell is a complicated behavior influenced by the current density,uniformity,and ion-diffusion distance,etc.The anisotropism of the lithiation/delithiation degree is usually inevitable,and even worse,due to a trend of big-size cell design,typically such as 4680 and blade cells,which accelerated a battery failure during repeat lithiation and delithiation of cathodes.Inspire by that,two big-size pouch cells with big sizes,herein,are selected to reveal the ion-diffusion dependency of the cathodes at different locations.Interestingly,we find that the LiCoO_(2) pouch cell exhibits ~5 A h loss after 120 charge-discharge cycles,but a 15 A h loss is verified in a LiNixMnyCO_(1-x)-yO_(2)(NCM) cell.Synchrotron-based imaging analysis indicates that higher ion-diffusion rates in the LiCoO_(2)than that in the LiNixMnyCO_(1-x)-yO_(2)is the determined factor for the anisotropic cathode fading,which is responsible for a severe mechanical issue of particle damage,such as cracks and even pulverization,in the cathode materials.Meanwhile,we verify the different locations at the near-tab and bottom of the electrode make it worse due to the ion-diffusion kinetics and temperature,inducing a spatially uneven electrochemistry in the big-size pouch cell.The findings give an in-depth insight into pouch cell failure and make a guideline for high-energy cell design and development.

Easily Obtaining Excellent Performance High-voltage LiCoO_(2)via Pr_(6)O_(11)Modification

Developing an effective method to synthesize high-performance high-voltage LiCoO_(2) is essential for its industrialization in lithium batteries(LIBs).This work proposes a simple mass-produced strategy for the first time,that is,negative temperature coefficient thermosensitive Pr_(6)O_(11) nanoparticles are uniformly modified on LiCoO_(2) to prepare LiCoO_(2)@Pr_(6)O_(11)(LCO@PrO)via a liquid-phase mixing combined with annealing method.Tested at 274 mA g−1,the modified LCO@PrO electrodes deliver excellent 4.5 V high-voltage cycling performance with capacity retention ratios of 90.8%and 80.5%at 25 and 60℃,being much larger than those of 22.8%and 63.2%for bare LCO electrodes.Several effective strategies were used to clearly unveil the performance enhancement mechanism induced by Pr_(6)O_(11) modification.It is discovered that Pr_(6)O_(11) can improve interface compatibility,exhibit improved conductivity at elevated temperature,thus enhance the Li^(+)diffusion kinetics,and suppress the phase transformation of LCO and its resulting mechanical stresses.The 450 mAh LCO@PrO‖graphite pouch cells show excellent LIB performance and improved thermal safety characteristics.Importantly,the energy density of such pouch cell was increased even by~42%at 5 C.This extremely convenient technology is feasible for producing high-energy density LIBs with negligible cost increase,undoubtedly providing important academic inspiration for industrialization.