Comprehensive analyses on thermal runaway mechanisms are critically vital to achieve the safe lithium-sulfur(Li-S)batteries.The reactions between dissolved higher-order polysulfides and Li metal were found to be the o...Comprehensive analyses on thermal runaway mechanisms are critically vital to achieve the safe lithium-sulfur(Li-S)batteries.The reactions between dissolved higher-order polysulfides and Li metal were found to be the origins for the thermal runaway of 1.0 Ah cycled Li-S pouch cells.16-cycle pouch cell indicates high safety,heating from 30 to 300 ℃ without thermal runaway,while 16-cycle pouch cell with additional electrolyte undergoes severe thermal runaway at 147.9 ℃,demonstrating the key roles of the electrolyte on the thermal safety of batteries.On the contrary,thermal runaway does not occur for 45-cycle pouch cell despite the addition of the electrolyte.It is found that the higher-order polysulfides(Li_(2)S_(x) ≥ 6)are discovered in 16-cycle electrolyte while the sulfur species in 45-cycle electrolyte are Li_(2)S_(x) ≤ 4.In addition,strong exothermic reactions are discovered between cycled Li and dissolved higher-order polysulfide(Li_(2)S_(6) and Li_(2)S_(8))at 153.0 ℃,driving the thermal runaway of cycled Li-S pouch cells.This work uncovers the potential safety risks of Li-S batteries and negative roles of the polysulfide shuttle for Li-S batteries from the safety view.展开更多
During the course of inflammatory bowel disease (IBD), surgery may be needed. Approximately 20% of patients with ulcerative colitis (UC) will require surgery, whereas up to 80% of Crohn's disease (CD) patients wil...During the course of inflammatory bowel disease (IBD), surgery may be needed. Approximately 20% of patients with ulcerative colitis (UC) will require surgery, whereas up to 80% of Crohn's disease (CD) patients will undergo an operation during their lifetime. For UC patients requiring surgery, total proctocolectomy and ileoanal pouch anastomosis (IPAA) is the operation of choice as it provides a permanent cure and good quality of life. Nevertheless a permanent stoma is a good option in selected patients, especially the elderly. Minimally invasive surgery has replaced the conventional open approach in many specialized centres worldwide. Laparoscopic colectomy and restorative IPAA is rapidly becoming the standard of care in the treatment of UC requiring surgery, whilst laparoscopic ileo-cecal resection is already the new gold standard in the treatment of complicated CD of terminal ileum. Short term advantages of laparoscopic surgery includes faster recovery time and reduced requirement for analgesics. It is, however, in the long term that minimally invasive surgery has demonstrated its superiority over the open approach. A better cosmesis, a reduced number of incisional hernias and fewer adhesions are the long term advantages of laparoscopy in IBD surgery. A reduction in abdominal adhesions is of great benefit when a second operation is needed in CD and this influences positively the pregnancy rate in young women undergoing restorative IPAA. In developing the therapeutic plan for IBD patients it should be recognized that the surgical approach to the abdomen has changed and that surgical treatment of complicated IBD can be safely performed with a true minimally invasive approach with great patient satisfaction.展开更多
High-energy-density lithium metal batteries(LMBs)are widely accepted as promising next-generation energy storage systems.However,the safety features of practical LMBs are rarely explored quantitatively.Herein,the ther...High-energy-density lithium metal batteries(LMBs)are widely accepted as promising next-generation energy storage systems.However,the safety features of practical LMBs are rarely explored quantitatively.Herein,the thermal runaway behaviors of a 3.26 Ah(343 Wh kg^(−1))Li|LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)pouch cell in the whole life cycle are quantitatively investigated by extended volume-accelerating rate calorimetry and differential scanning calorimetry.By thermal failure analyses on pristine cell with fresh Li metal,activated cell with once plated dendrites,and 20-cycled cell with large quantities of dendrites and dead Li,dendrite-accelerated thermal runaway mechanisms including reaction sequence and heat release contribution are reached.Suppressing dendrite growth and reducing the reactivity between Li metal anode and electrolyte at high temperature are effective strategies to enhance the safety performance of LMBs.These findings can largely enhance the understanding on the thermal runaway behaviors of Li metal pouch cells in practical working conditions.展开更多
Despite the new and ever expanding array of medications for the treatment of inflammatory bowel disease (IBD), there are still clear indications for operative management of IBD and its complications. We present an ove...Despite the new and ever expanding array of medications for the treatment of inflammatory bowel disease (IBD), there are still clear indications for operative management of IBD and its complications. We present an overview of indications, procedures, considerations, and controversies in the surgical therapy of IBD.展开更多
Ulcerative colitis (UC) is a relapsing and remitting disease characterised by chronic mucosal and submucosal inflammation of the colon and rectum. Treatment may vary depending upon the extent and severity of inflammat...Ulcerative colitis (UC) is a relapsing and remitting disease characterised by chronic mucosal and submucosal inflammation of the colon and rectum. Treatment may vary depending upon the extent and severity of inflammation. Broadly speaking medical treatments aim to induce and then maintain remission. Surgery is indicated for inflammatory disease that is refractory to medical treatment or in cases of neoplastic transformation. Approximately 25% of patients with UC ultimately require colectomy. Ileal pouch-anal anastomosis (IPAA) has become the standard of care for patients with ulcerative colitis who ultimately require colectomy. This review will examine indications for IPAA, patient selection, technical aspects of surgery, management of complications and long term outcome following this procedure.展开更多
To meet the requirements of electronic vehicles(EVs) and hybrid electric vehicles(HEVs),the high energy density Li Ni_(0.8) Co_(0.15) Al_(0.05) O_2(NCA) cathode and Si–C anode have attracted more attention.Here we re...To meet the requirements of electronic vehicles(EVs) and hybrid electric vehicles(HEVs),the high energy density Li Ni_(0.8) Co_(0.15) Al_(0.05) O_2(NCA) cathode and Si–C anode have attracted more attention.Here we report the thermal behaviors of NCA/Si–C pouch cell during the charge/discharge processes at different current densities.The total heat generations are derived from the surface temperature change during electrochemical Li+insertion/extraction in adiabatic surrounding.The reversible heat is determined by the entropic coefficients,which are related with open-circuit voltage at different temperatures; while the irreversible heat is determined by the internal resistance,which can be obtained via V–I characteristic,electrochemical impedance spectroscopy and hybrid pulse power characterization(HPPC).During the electrochemical process,the reversible heat contributes less than 10% to total heat generation; and the heat generated in charge process is less than that in discharge process.The results of thermal behaviors analyses are conducive to understanding the safety management and paving the way for building a reliable thermal model of high energy density lithium ion battery.展开更多
Gardner syndrome (GS) is an autosomal dominant disease characterized by the presence of colonic polyposis, osteoma and soft tissue tumors. It is regarded as a clinical subgroup of familial adenomatous polyposis (FAP) ...Gardner syndrome (GS) is an autosomal dominant disease characterized by the presence of colonic polyposis, osteoma and soft tissue tumors. It is regarded as a clinical subgroup of familial adenomatous polyposis (FAP) and may present at any age from 2 mo to 70 years with a variety of symptoms, either colonic or extracolonic. We present a case of a 23-year-old female patient with GS who presented with gastric polyposis and was successively treated with restorative proctocolectomy in combination with ileal pouch anal anastomosis (RPC/ IPAA), ileostomy, ileostomy closure operation, snare polypectomy during 8 mo. After operation, the patient took oral traditional Chinese medicine pills made of Fructus mume and Bombyx batryticatu for about 6 mo. The innutrition and anaemia of this patient were gradually improved. Gastroscopy showed that the remnant gastric polypi gradually decreased and finally disappeared 19 mo after the first operation. The patient had 2-3 times of solid stool per day at the time we wrote this paper.展开更多
Restorative proctocolectomy is the most common surgical option for patients with familial adenomatous polyposis(FAP). However,adenomas may develop in the ileal pouch mucosa over time,and even carcinoma in the pouch ha...Restorative proctocolectomy is the most common surgical option for patients with familial adenomatous polyposis(FAP). However,adenomas may develop in the ileal pouch mucosa over time,and even carcinoma in the pouch has been reported. We therefore reviewed the prevalence,nature,and treatment of adenomas and carcinoma that develop after proctocolectomy in the ileal pouch mucosa in patients with FAP. In 25 reports that were reviewed,the incidence of adenomas in the ileal pouch varied from 6.7% to 73.9%. Several potential factors that favor the development of pouch polyposis have been investigated,but many remain controversial. Nevertheless,it seems certain that the age of the pouch is important. The risk appears to be 7%to 16% after 5 years,35% to 42% after 10 years,and75% after 15 years. On the other hand,only 21 cases of ileal pouch carcinoma have been recorded in the literature to date. The diagnosis of pouch carcinoma was made between 3 to 20 years(median,10 years) after pouch construction. Although the risk of malignant transformation in ileal pouches is probably low,it is not negligible,and the long-term risk cannot presently be well quantified. Regular endoscopic surveillance,especially using chromoendoscopy,is recommended.展开更多
Aim To investigate the role of the Chinese herbal medicine Xianhuayin on the reversal of 7,12-dimethylbenz[a]anthracene （DMBA）-induced premalignant mucosal lesions in the oral buccal pouch of golden hamsters. Method...Aim To investigate the role of the Chinese herbal medicine Xianhuayin on the reversal of 7,12-dimethylbenz[a]anthracene （DMBA）-induced premalignant mucosal lesions in the oral buccal pouch of golden hamsters. Methodology The animals were randomly divided into a non-diseased control group （n=5） and an experimental group including 50 animals in which the buccal mucosa had been painted with DMBA （0.5% in acetone） to generate an oral mucosa premalignant lesion. Animals in the experi- mental group were further divided into Xianhuayin-treated group （n=30）, untreated prem＇alignant lesion group （n=10） and normal saline （NS）-treated group （n=10）. The cheek （buccal） pouch mucosa of the golden hamsters in each group was observed with light and electron microscopy eight weeks after intragastric administration with NS or Xianhuayin. Results In the non-diseased control group, the buccal mucosa was keratinized and stratified squamous epithelium under a light microscope. In the untreated premalignant lesion group, variable degrees of epithelial dysplasia was observed. The irregular epithelial mucosa gradually became distinct in the Xianhuayin-treated group. Scanning electronic microscopic （SEM） analysis showed that surface of the cells exhibited honeycomb structures in the hamster of untreated- group. The cells were morphologically irregular, overlapped and loosened in the untreated premalignant lesion group. Most of the cell surface exhibited honeycomb structure in the Xianhuayin-treated group. Transmission electronic micro- scopic （TEM） analysis showed that buccal mucosal epithelial cells were morphologically regular in the non-diseased control group. Desmosomes and tonofibrils were reduced and the nucleus was morphologically irregular in the untreated premalignant lesion group. In the Xianhuayin-treated group, the widening intercellular gap was gradually reduced, desmosomes and the cells becoming morphologically regular. No significant difference was observed between the hamsters in N展开更多
Lithium-sulfur （Li-S） batteries with intrinsic merits in high theoretical energy density are the most promising candidate as the next-generation power sources. The strategy to achieve a high utilization of active ma...Lithium-sulfur （Li-S） batteries with intrinsic merits in high theoretical energy density are the most promising candidate as the next-generation power sources. The strategy to achieve a high utilization of active materials with high energy efficiency is strongly requested for practical applications with less energy loss during repeated cycling. In this contribution, a metal/nanocarbon layer current collector is proposed to enhance the redox reactions of polysulfides in a working Li-S cell. Such a concept is demon- strated by coating graphene-carbon nanotube hybrids （GNHs） on routine aluminum （AI） foil current collectors. The interracial conductivity and adhesion between the current collector and active material are significantly enhanced. Such novel cell configuration with metal/nanocarbon layer current collectors affords abundant Li ions for rapid redox reactions with small overpotential. Consequently, the Li-S cells with nanostructured current collectors exhibit an initial discharge capacity of 1,113 mAh g-1 at 0.5 C, which is -300 mAh g-1 higher than those without a GNH coating layer. The capacity retention is 73% for cells with GNH after 300 cycles. A reduced voltage hysteresis and a high energy efficiency of ca. 90% are therefore achieved. Moreover, the AI/GNH layer current collectors are easily implanted into current cell assembly process for energy storage devices based on complex multi-electron redox reactions （e.g., Li-S batteries, Li-O2 batteries, fuel cells, and flow batteries）.展开更多
The dependence on portable devices and electrical vehicles has triggered the awareness on the energy storage systems with ever-growing energy density.Lithium metal batteries(LMBs)has revived and attracted considerable...The dependence on portable devices and electrical vehicles has triggered the awareness on the energy storage systems with ever-growing energy density.Lithium metal batteries(LMBs)has revived and attracted considerable attention due to its high volumetric(2046 m Ah cm-3),gravimetric specific capacity(3862 m Ah g^(-1))and the lowest reduction potential(-3.04 V vs.SHE.).However,during the electrochemical process of lithium anode,the growth of lithium dendrite constitutes the biggest stumbling block on the road to LMBs application.The undesirable dendrite not only limit the Coulombic efficiency(CE)of LMBs,but also cause thermal runaway and other safety issues due to short-circuits.Understanding the mechanisms of lithium nucleation and dendrite growth provides insights to solve these problems.Herein,we summarize the electrochemical models that inherently describe the lithium nucleation and dendrite growth,such as the thermodynamic,electrodeposition kinetics,internal stress,and interface transmission models.Essential parameters of temperature,current density,internal stress and interfacial Li+flux are focused.To improve the LMBs performance,state-of-the-art optimization procedures have been developed and systematically illustrated with the intrinsic regulation principles for better lithium anode stability,including electrolyte optimization,artificial interface layers,threedimensional hosts,external field,etc.Towards practical applications of LMBs,the current development of pouch cell LMBs have been further introduced with different assembly systems and fading mechanism.However,challenges and obstacles still exist for the development of LMBs,such as in-depth understanding and in-situ observation of dendrite growth,the surface protection under extreme condition and the self-healing of solid electrolyte interface.展开更多
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 c...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.展开更多
Developing sulfur cathodes with high catalytic activity on accelerating the sluggish redox kinetics of lithium polysulfides(Li PSs) and unveiling their mechanisms are pivotal for advanced lithium–sulfur(Li–S)batteri...Developing sulfur cathodes with high catalytic activity on accelerating the sluggish redox kinetics of lithium polysulfides(Li PSs) and unveiling their mechanisms are pivotal for advanced lithium–sulfur(Li–S)batteries. Herein, MoS2 is verified to reduce the Gibbs free energy for rate-limiting step of sulfur reduction and the dissociation energy of lithium sulfide(Li2 S) for the first time employing theoretical calculations. The Mo S2 nanosheets coated on mesoporous hollow carbon spheres(MHCS) are then reasonably designed as a sulfur host for high-capacity and long-life Li–S battery, in which MHCS can guarantee the high sulfur loading and fast electron/ion transfer. It is revealed that the shuttle effect is efficiently inhibited because of the boosted conversion of Li PSs. As a result, the coin cell based on the MHCS@Mo S2-S cathode exhibits stable cycling performance maintaining 735.7 mAh g^(-1) after 500 cycles at 1.0 C. More importantly, the pouch cell employing the MHCS@Mo S2-S cathodes achieves high specific capacity of1353.2 m Ah g^(-1) and prominent cycle stability that remaining 960.0 m Ah g^(-1) with extraordinary capacity retention of 79.8% at 0.1 C after 170 cycles. Therefore, this work paves a new avenue for developing practical high specific energy and long-life pouch-type Li–S batteries.展开更多
Recently introduced in the treatment algorithms and guidelines for the treatment of ulcerative colitis,biological therapy is an effective treatment option for patients with an acute severe flare not responsive to conv...Recently introduced in the treatment algorithms and guidelines for the treatment of ulcerative colitis,biological therapy is an effective treatment option for patients with an acute severe flare not responsive to conventional treatments and for patients with steroid dependent disease.The reduction in hospitalization and surgical intervention for patients affected by ulcerative colitis after the introduction of biologic treatment remains to be proven.Furthermore,these agents seem to be associated with increase in cost of treatment and risk for serious postoperative complications.Restorative proctocolectomy with ileal pouch-anal anastomosis is the surgical treatment of choice in ulcerative colitis patients.Surgery is traditionally recommended as salvage therapy when medical management fails,and,despite advances in medical therapy,colectomy rates remain unchanged between 20% and 30%.To overcome the reported increase in postoperative complications in patients on biologic therapies,several surgical strategies have been developed to maintain long-term pouch failure rate around 10%,as previously reported.Surgical staging along with the development of minimally invasive surgery are among the most promising advances in this field.展开更多
基金supported by the National Key Research and Development Program(grant No.2021YFB2500300)National Natural Science Foundation of China(grant Nos.22179070,22075029,U1932220)+2 种基金Beijing Municipal Natural Science Foundation(grant No.Z200011)the Natural Science Foundation of Jiangsu Province(grant No.BK20220073)the Fundamental Research Funds for the Central Universities(grant No.2242022R10082).
文摘Comprehensive analyses on thermal runaway mechanisms are critically vital to achieve the safe lithium-sulfur(Li-S)batteries.The reactions between dissolved higher-order polysulfides and Li metal were found to be the origins for the thermal runaway of 1.0 Ah cycled Li-S pouch cells.16-cycle pouch cell indicates high safety,heating from 30 to 300 ℃ without thermal runaway,while 16-cycle pouch cell with additional electrolyte undergoes severe thermal runaway at 147.9 ℃,demonstrating the key roles of the electrolyte on the thermal safety of batteries.On the contrary,thermal runaway does not occur for 45-cycle pouch cell despite the addition of the electrolyte.It is found that the higher-order polysulfides(Li_(2)S_(x) ≥ 6)are discovered in 16-cycle electrolyte while the sulfur species in 45-cycle electrolyte are Li_(2)S_(x) ≤ 4.In addition,strong exothermic reactions are discovered between cycled Li and dissolved higher-order polysulfide(Li_(2)S_(6) and Li_(2)S_(8))at 153.0 ℃,driving the thermal runaway of cycled Li-S pouch cells.This work uncovers the potential safety risks of Li-S batteries and negative roles of the polysulfide shuttle for Li-S batteries from the safety view.
文摘During the course of inflammatory bowel disease (IBD), surgery may be needed. Approximately 20% of patients with ulcerative colitis (UC) will require surgery, whereas up to 80% of Crohn's disease (CD) patients will undergo an operation during their lifetime. For UC patients requiring surgery, total proctocolectomy and ileoanal pouch anastomosis (IPAA) is the operation of choice as it provides a permanent cure and good quality of life. Nevertheless a permanent stoma is a good option in selected patients, especially the elderly. Minimally invasive surgery has replaced the conventional open approach in many specialized centres worldwide. Laparoscopic colectomy and restorative IPAA is rapidly becoming the standard of care in the treatment of UC requiring surgery, whilst laparoscopic ileo-cecal resection is already the new gold standard in the treatment of complicated CD of terminal ileum. Short term advantages of laparoscopic surgery includes faster recovery time and reduced requirement for analgesics. It is, however, in the long term that minimally invasive surgery has demonstrated its superiority over the open approach. A better cosmesis, a reduced number of incisional hernias and fewer adhesions are the long term advantages of laparoscopy in IBD surgery. A reduction in abdominal adhesions is of great benefit when a second operation is needed in CD and this influences positively the pregnancy rate in young women undergoing restorative IPAA. In developing the therapeutic plan for IBD patients it should be recognized that the surgical approach to the abdomen has changed and that surgical treatment of complicated IBD can be safely performed with a true minimally invasive approach with great patient satisfaction.
基金Beijing Municipal Natural Science Foundation(Z200011)National Key Research and Development Program(2021YFB2500300)National Natural Science Foundation of China(22179070,22075029,U1932220),the“Shuimu Tsinghua Scholar Program of Tsinghua University”,and Mercedes-Benz AG.Xiang-Qun Xu and Xin-Bing Cheng contributed equally to this work.
文摘High-energy-density lithium metal batteries(LMBs)are widely accepted as promising next-generation energy storage systems.However,the safety features of practical LMBs are rarely explored quantitatively.Herein,the thermal runaway behaviors of a 3.26 Ah(343 Wh kg^(−1))Li|LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)pouch cell in the whole life cycle are quantitatively investigated by extended volume-accelerating rate calorimetry and differential scanning calorimetry.By thermal failure analyses on pristine cell with fresh Li metal,activated cell with once plated dendrites,and 20-cycled cell with large quantities of dendrites and dead Li,dendrite-accelerated thermal runaway mechanisms including reaction sequence and heat release contribution are reached.Suppressing dendrite growth and reducing the reactivity between Li metal anode and electrolyte at high temperature are effective strategies to enhance the safety performance of LMBs.These findings can largely enhance the understanding on the thermal runaway behaviors of Li metal pouch cells in practical working conditions.
文摘Despite the new and ever expanding array of medications for the treatment of inflammatory bowel disease (IBD), there are still clear indications for operative management of IBD and its complications. We present an overview of indications, procedures, considerations, and controversies in the surgical therapy of IBD.
文摘Ulcerative colitis (UC) is a relapsing and remitting disease characterised by chronic mucosal and submucosal inflammation of the colon and rectum. Treatment may vary depending upon the extent and severity of inflammation. Broadly speaking medical treatments aim to induce and then maintain remission. Surgery is indicated for inflammatory disease that is refractory to medical treatment or in cases of neoplastic transformation. Approximately 25% of patients with UC ultimately require colectomy. Ileal pouch-anal anastomosis (IPAA) has become the standard of care for patients with ulcerative colitis who ultimately require colectomy. This review will examine indications for IPAA, patient selection, technical aspects of surgery, management of complications and long term outcome following this procedure.
基金supported by the National Key R&D Program of China:Trackling Key Technology for Development and Industrialization of Power Lithium Ion Battery with High Specific Energy (Grant No.2016YFB0100508)
文摘To meet the requirements of electronic vehicles(EVs) and hybrid electric vehicles(HEVs),the high energy density Li Ni_(0.8) Co_(0.15) Al_(0.05) O_2(NCA) cathode and Si–C anode have attracted more attention.Here we report the thermal behaviors of NCA/Si–C pouch cell during the charge/discharge processes at different current densities.The total heat generations are derived from the surface temperature change during electrochemical Li+insertion/extraction in adiabatic surrounding.The reversible heat is determined by the entropic coefficients,which are related with open-circuit voltage at different temperatures; while the irreversible heat is determined by the internal resistance,which can be obtained via V–I characteristic,electrochemical impedance spectroscopy and hybrid pulse power characterization(HPPC).During the electrochemical process,the reversible heat contributes less than 10% to total heat generation; and the heat generated in charge process is less than that in discharge process.The results of thermal behaviors analyses are conducive to understanding the safety management and paving the way for building a reliable thermal model of high energy density lithium ion battery.
文摘Gardner syndrome (GS) is an autosomal dominant disease characterized by the presence of colonic polyposis, osteoma and soft tissue tumors. It is regarded as a clinical subgroup of familial adenomatous polyposis (FAP) and may present at any age from 2 mo to 70 years with a variety of symptoms, either colonic or extracolonic. We present a case of a 23-year-old female patient with GS who presented with gastric polyposis and was successively treated with restorative proctocolectomy in combination with ileal pouch anal anastomosis (RPC/ IPAA), ileostomy, ileostomy closure operation, snare polypectomy during 8 mo. After operation, the patient took oral traditional Chinese medicine pills made of Fructus mume and Bombyx batryticatu for about 6 mo. The innutrition and anaemia of this patient were gradually improved. Gastroscopy showed that the remnant gastric polypi gradually decreased and finally disappeared 19 mo after the first operation. The patient had 2-3 times of solid stool per day at the time we wrote this paper.
文摘Restorative proctocolectomy is the most common surgical option for patients with familial adenomatous polyposis(FAP). However,adenomas may develop in the ileal pouch mucosa over time,and even carcinoma in the pouch has been reported. We therefore reviewed the prevalence,nature,and treatment of adenomas and carcinoma that develop after proctocolectomy in the ileal pouch mucosa in patients with FAP. In 25 reports that were reviewed,the incidence of adenomas in the ileal pouch varied from 6.7% to 73.9%. Several potential factors that favor the development of pouch polyposis have been investigated,but many remain controversial. Nevertheless,it seems certain that the age of the pouch is important. The risk appears to be 7%to 16% after 5 years,35% to 42% after 10 years,and75% after 15 years. On the other hand,only 21 cases of ileal pouch carcinoma have been recorded in the literature to date. The diagnosis of pouch carcinoma was made between 3 to 20 years(median,10 years) after pouch construction. Although the risk of malignant transformation in ileal pouches is probably low,it is not negligible,and the long-term risk cannot presently be well quantified. Regular endoscopic surveillance,especially using chromoendoscopy,is recommended.
基金supported by grants from the highly distinguished Oncology Subject Foundation of Colleges in Hebei Province
文摘Aim To investigate the role of the Chinese herbal medicine Xianhuayin on the reversal of 7,12-dimethylbenz[a]anthracene （DMBA）-induced premalignant mucosal lesions in the oral buccal pouch of golden hamsters. Methodology The animals were randomly divided into a non-diseased control group （n=5） and an experimental group including 50 animals in which the buccal mucosa had been painted with DMBA （0.5% in acetone） to generate an oral mucosa premalignant lesion. Animals in the experi- mental group were further divided into Xianhuayin-treated group （n=30）, untreated prem＇alignant lesion group （n=10） and normal saline （NS）-treated group （n=10）. The cheek （buccal） pouch mucosa of the golden hamsters in each group was observed with light and electron microscopy eight weeks after intragastric administration with NS or Xianhuayin. Results In the non-diseased control group, the buccal mucosa was keratinized and stratified squamous epithelium under a light microscope. In the untreated premalignant lesion group, variable degrees of epithelial dysplasia was observed. The irregular epithelial mucosa gradually became distinct in the Xianhuayin-treated group. Scanning electronic microscopic （SEM） analysis showed that surface of the cells exhibited honeycomb structures in the hamster of untreated- group. The cells were morphologically irregular, overlapped and loosened in the untreated premalignant lesion group. Most of the cell surface exhibited honeycomb structure in the Xianhuayin-treated group. Transmission electronic micro- scopic （TEM） analysis showed that buccal mucosal epithelial cells were morphologically regular in the non-diseased control group. Desmosomes and tonofibrils were reduced and the nucleus was morphologically irregular in the untreated premalignant lesion group. In the Xianhuayin-treated group, the widening intercellular gap was gradually reduced, desmosomes and the cells becoming morphologically regular. No significant difference was observed between the hamsters in N
基金supported by National Key Research and Development Program of China (2016YFA0202500, 2015CB932500)the National Natural Science Foundation of China (21776019, 21422604)
文摘Lithium-sulfur （Li-S） batteries with intrinsic merits in high theoretical energy density are the most promising candidate as the next-generation power sources. The strategy to achieve a high utilization of active materials with high energy efficiency is strongly requested for practical applications with less energy loss during repeated cycling. In this contribution, a metal/nanocarbon layer current collector is proposed to enhance the redox reactions of polysulfides in a working Li-S cell. Such a concept is demon- strated by coating graphene-carbon nanotube hybrids （GNHs） on routine aluminum （AI） foil current collectors. The interracial conductivity and adhesion between the current collector and active material are significantly enhanced. Such novel cell configuration with metal/nanocarbon layer current collectors affords abundant Li ions for rapid redox reactions with small overpotential. Consequently, the Li-S cells with nanostructured current collectors exhibit an initial discharge capacity of 1,113 mAh g-1 at 0.5 C, which is -300 mAh g-1 higher than those without a GNH coating layer. The capacity retention is 73% for cells with GNH after 300 cycles. A reduced voltage hysteresis and a high energy efficiency of ca. 90% are therefore achieved. Moreover, the AI/GNH layer current collectors are easily implanted into current cell assembly process for energy storage devices based on complex multi-electron redox reactions （e.g., Li-S batteries, Li-O2 batteries, fuel cells, and flow batteries）.
基金supported by the National Natural Science Foundation of China(51804290,22075025)the Beijing Natural Science Foundation(L182023)+1 种基金the Science and Technology Project of Global Energy Interconnection Research Institute Co.Ltd.(SGGR0000WLJS1900858)the Beijing Institute of Technology Research Fund Program for Young Scholars(2019CX04092)。
文摘The dependence on portable devices and electrical vehicles has triggered the awareness on the energy storage systems with ever-growing energy density.Lithium metal batteries(LMBs)has revived and attracted considerable attention due to its high volumetric(2046 m Ah cm-3),gravimetric specific capacity(3862 m Ah g^(-1))and the lowest reduction potential(-3.04 V vs.SHE.).However,during the electrochemical process of lithium anode,the growth of lithium dendrite constitutes the biggest stumbling block on the road to LMBs application.The undesirable dendrite not only limit the Coulombic efficiency(CE)of LMBs,but also cause thermal runaway and other safety issues due to short-circuits.Understanding the mechanisms of lithium nucleation and dendrite growth provides insights to solve these problems.Herein,we summarize the electrochemical models that inherently describe the lithium nucleation and dendrite growth,such as the thermodynamic,electrodeposition kinetics,internal stress,and interface transmission models.Essential parameters of temperature,current density,internal stress and interfacial Li+flux are focused.To improve the LMBs performance,state-of-the-art optimization procedures have been developed and systematically illustrated with the intrinsic regulation principles for better lithium anode stability,including electrolyte optimization,artificial interface layers,threedimensional hosts,external field,etc.Towards practical applications of LMBs,the current development of pouch cell LMBs have been further introduced with different assembly systems and fading mechanism.However,challenges and obstacles still exist for the development of LMBs,such as in-depth understanding and in-situ observation of dendrite growth,the surface protection under extreme condition and the self-healing of solid electrolyte interface.
基金the Mitchell J.Notaras Fellowship in Colorectal Surgery
文摘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.
基金supported by the funding from the Strategy Priority Research Program of Chinese Academy of Science (Grant No. XDA17020404)DICP&QIBEBT (DICP&QIBEBT UN201702)+8 种基金R&D Projects in Key Areas of Guangdong Province (2019B090908001)Science and Technology Innovation Foundation of Dalian (2018J11CY020)Defense Industrial Technology Development Program (JCKY2018130C107)National Natural Science Foundation of China (Grants 51872283)Liao Ning Revitalization Talents Program (Grant XLYC1807153)Natural Science Foundation of Liaoning Province (Grant 20180510038)DICP (DICP ZZBS201708, DICP ZZBS201802)DNL Cooperation FundCAS (DNL180310, DNL180308, DNL201912, and DNL201915)。
文摘Developing sulfur cathodes with high catalytic activity on accelerating the sluggish redox kinetics of lithium polysulfides(Li PSs) and unveiling their mechanisms are pivotal for advanced lithium–sulfur(Li–S)batteries. Herein, MoS2 is verified to reduce the Gibbs free energy for rate-limiting step of sulfur reduction and the dissociation energy of lithium sulfide(Li2 S) for the first time employing theoretical calculations. The Mo S2 nanosheets coated on mesoporous hollow carbon spheres(MHCS) are then reasonably designed as a sulfur host for high-capacity and long-life Li–S battery, in which MHCS can guarantee the high sulfur loading and fast electron/ion transfer. It is revealed that the shuttle effect is efficiently inhibited because of the boosted conversion of Li PSs. As a result, the coin cell based on the MHCS@Mo S2-S cathode exhibits stable cycling performance maintaining 735.7 mAh g^(-1) after 500 cycles at 1.0 C. More importantly, the pouch cell employing the MHCS@Mo S2-S cathodes achieves high specific capacity of1353.2 m Ah g^(-1) and prominent cycle stability that remaining 960.0 m Ah g^(-1) with extraordinary capacity retention of 79.8% at 0.1 C after 170 cycles. Therefore, this work paves a new avenue for developing practical high specific energy and long-life pouch-type Li–S batteries.
文摘Recently introduced in the treatment algorithms and guidelines for the treatment of ulcerative colitis,biological therapy is an effective treatment option for patients with an acute severe flare not responsive to conventional treatments and for patients with steroid dependent disease.The reduction in hospitalization and surgical intervention for patients affected by ulcerative colitis after the introduction of biologic treatment remains to be proven.Furthermore,these agents seem to be associated with increase in cost of treatment and risk for serious postoperative complications.Restorative proctocolectomy with ileal pouch-anal anastomosis is the surgical treatment of choice in ulcerative colitis patients.Surgery is traditionally recommended as salvage therapy when medical management fails,and,despite advances in medical therapy,colectomy rates remain unchanged between 20% and 30%.To overcome the reported increase in postoperative complications in patients on biologic therapies,several surgical strategies have been developed to maintain long-term pouch failure rate around 10%,as previously reported.Surgical staging along with the development of minimally invasive surgery are among the most promising advances in this field.
