Methanation is an effective way to efficiently utilize product gas generated from the pyrolysis and gasification of organic solid wastes.To deeply study the heat transfer and mass transfer mechanisms in the reactor,a ...Methanation is an effective way to efficiently utilize product gas generated from the pyrolysis and gasification of organic solid wastes.To deeply study the heat transfer and mass transfer mechanisms in the reactor,a successful three-dimensional comprehensive model has been established.Multiphase flow behavior and heat transfer mechanisms were investigated under reference working conditions.Temperature is determined by the heat release of the reaction and the heat transfer of the gas-solid flow.The maximum temperature can reach 951 K where the catalyst gathers.In the simulation,changes in the gas inlet velocity and catalyst flow rate were made to explore their effects on CO conversion rate and temperature for optimization purposes.As the inlet gas velocity increases from 2.78 to 4.79 m/s,the CO conversion rate decreases from 81.6%to 72.4%.However,more heat is removed from the reactor,and the temperature rise increases from 78.03 to 113.49 K.When the catalyst flow rate is increased from 7.18 to 17.96 kg/(m^(2)·s),the mass of the catalyst in the reactor is increased from 0.0019 to 0.0042 kg,and the CO conversion rate is increased from 66.8%to 81.5%.However,this increases the maximum temperature in the reactor from 940.0 to 966.4 K.展开更多
Combustion of agricultural organic solid waste(AOSW)was an ideal solution for their resource utilization in view of their massive annual production and great potential for reduction of fossil fuel utilization.However,...Combustion of agricultural organic solid waste(AOSW)was an ideal solution for their resource utilization in view of their massive annual production and great potential for reduction of fossil fuel utilization.However,high alkali and alkaline earth metals(AAEMs)content in the feedstock can arose severe fouling and slagging issues and thus prohibiting its vast utilization.In this study,a semi-continuous water washing method was proposed to preliminarily remove AAEMs from agricultural organic solid waste and its effects on the combustion behaviors of washed solid product were investigated.Results showed that the combustion index S were improved to 2.63×10-6,over 68%of the total ashes were removed from the cotton stalk,and 96.3%,89.0%and 74.7%of K,Na and Mg were effectively removed,respectively.Moreover,the softening temperature of low temperature ash from the washed sample was as high as 1450◦C,538◦C higher than the low temperature ash from the original sample;the base acid ratio and fouling index were improved from high slagging and fouling risk(1.7 and 90.8)of the original organic solid waste to low and medium risk(0.4 and 3.5),respectively.All these results signified the contributing effect of proposed semi-continuous water washing method on the combustion of agricultural organic solid waste.In a word,this study provided a promising method for fouling and slagging inhibition during the agricultural organic solid waste combustion.展开更多
BACKGROUND De novo malignancy is a leading cause of late morbidity and mortality in liver transplant recipients.Cumulative immunosuppression has been shown to contribute to post-transplant malignancy(PTM)risk.There is...BACKGROUND De novo malignancy is a leading cause of late morbidity and mortality in liver transplant recipients.Cumulative immunosuppression has been shown to contribute to post-transplant malignancy(PTM)risk.There is emerging evidence on the differential carcinogenic risk profile of individual immunosuppressive drugs,independent of the net effect of immunosuppression.Calcineurin inhibitors such as tacrolimus may promote tumourigenesis,whereas mycophenolic acid(MPA),the active metabolite of mycophenolate mofetil,may limit tumour progression.Liver transplantation(LT)is relatively unique among solid organ transplantation in that immunosuppression monotherapy with either tacrolimus or MPA is often achievable,which makes careful consideration of the risk-benefit profile of these immunosuppression agents particularly relevant for this cohort.However,there is limited clinical data on this subject in both LT and other solid organ transplant recipients.AIM To investigate the relative carcinogenicity of tacrolimus and MPA in solid organ transplantation.METHODS A literature search was conducted using MEDLINE and Embase databases using the key terms“solid organ transplantation”,“tacrolimus”,“mycophenolic acid”,and“carcinogenicity”,in order to identify relevant articles published in English between 1st January 2002 to 11th August 2022.Related terms,synonyms and explosion of MeSH terms,Boolean operators and truncations were also utilised in the search.Reference lists of retrieved articles were also reviewed to identify any additional articles.Excluding duplicates,abstracts from 1230 records were screened by a single reviewer,whereby 31 records were reviewed in detail.Full-text articles were assessed for eligibility based on pre-specified inclusion and exclusion criteria.RESULTS A total of 6 studies were included in this review.All studies were large population registries or cohort studies,which varied in transplant era,type of organ transplanted and immunosuppression protocol used.Overall,there was no clear difference demonstrated between tacrolimus and MPA in de novo PTM risk following solid organ transplantation.Furthermore,no study provided a direct comparison of carcinogenic risk between tacrolimus and MPA monotherapy in solid organ transplantation recipients.CONCLUSION The contrasting carcinogenic risk profiles of tacrolimus and MPA demonstrated in previous experimental studies,and its application in solid organ transplantation,is yet to be confirmed in clinical studies.Thus,the optimal choice of immunosuppression drug to use as maintenance monotherapy in LT recipients is not supported by a strong evidence base and remains unclear.展开更多
Antibiotic resistance genes(ARGs)have been diffusely detected in several kinds of organic solid waste,such as livestock manure,sludge,antibiotic fermentation residues,and food waste,thus attracting great attention.Aer...Antibiotic resistance genes(ARGs)have been diffusely detected in several kinds of organic solid waste,such as livestock manure,sludge,antibiotic fermentation residues,and food waste,thus attracting great attention.Aerobic composting,which is an effective,harmless treatment method for organic solid waste to promote recycling,has been identified to also aid in ARG reduction.However,the effect of composting in removing ARGs from organic solid waste has recently become controversial.Thus,this article summarizes and reviews the research on ARGs in relation to composting in the past 5 years.ARGs in organic solid waste could spread in different environmental media,including soil and the atmosphere,which could widen environmental risks.However,the conventional composting technology had limited effect on ARGs removal from organic solid waste.Improved composting processes,such as hyperthermophilic temperature composting,could effectively remove ARGs,and the HGT of ARGs and the microbial communities are identified as vital influencing factors.Currently,during the composting process,ARGs were mainly affected by three response pathways,(Ⅰ)“Microenvironment-ARGs”;(Ⅱ)“Microenvironment-microorganisms-ARGs”;(Ⅲ)“Microorganisms-horizontal gene transfer-ARGs”,respectively.Response pathway Ⅱ had been studied the most which was believed that microbial community was an important factor affecting ARGs.In response pathway Ⅲ,mainly believed that MGEs played an important role and paid less attention to eARGs.Further research on the role and impact of eARGs in ARGs may be considered in the future.It aims to provide support for further research on environmental risk control of ARGs in organic solid waste.展开更多
The geologic production of abiotic organic compounds has been the subject of increasing scientific attention due to their use in the global carbon flux balance,by chemosynthetic biological communities,and for energy r...The geologic production of abiotic organic compounds has been the subject of increasing scientific attention due to their use in the global carbon flux balance,by chemosynthetic biological communities,and for energy resources.Extensive analysis of methane(CH_(4))and other organics in diverse geologic settings,combined with thermodynamic modelings and laboratory simulations,have yielded insights into the distribution of specific abiotic organic molecules on Earth and the favorable conditions and pathways under which they form.This updated and comprehensive review summarizes published results of petrological,thermodynamic,and experimental investigations of possible pathways for the formation of particular species of abiotic simple hydrocarbon molecules such as CH_(4),and of complex hydrocarbon systems,e.g.,long-chain hydrocarbons and even solid carbonaceous matters,in various geologic processes,distinguished into three classes:(1)pre-to early planetary processes;(2)mantle and magmatic processes;and(3)the gas/water-rock reaction processes in low-pressure ultramafic rock and high-pressure subduction zone systems.We not only emphasize how organics are abiotically synthesized but also explore the role or changes of organics in evolutionary geological environments after synthesis,such as phase transitions or organic-mineral interactions.Correspondingly,there is an urgent need to explore the diversity of abiotic organic compounds prevailing on Earth.展开更多
This work is aimed at the development of new green composite materials through the incorporation of the solid organic waste(SOW)in a thermoplastic matrix.After being ground,the organic waste was exposed to a steriliza...This work is aimed at the development of new green composite materials through the incorporation of the solid organic waste(SOW)in a thermoplastic matrix.After being ground,the organic waste was exposed to a sterilization process,though an autoclave cycle,in order to obtain a complete removal of the bacterial activity.The SOW was found to have a high amount of water,about 65-70%,which made uneconomical its further treatment to reduce the water amount.Therefore,a water soluble polymer,poly(vinyl alcohol)(PVA)was chosen in order to produce SOW based blends.However,in order to reduce the viscosity of the PVA/SOW slurry,further amount of water was added.The very low viscosity attained by the water suspension allowed to process the PVA/SOW blends by a pressure-free process,for the production of samples,which were afterwards subjected to physical and mechanical characterization.Flexural tests showed the promising properties of the developed blends.In particular,the relevance of porosity was assessed.Increasing the water amount involved a signification increase of porosity,due to a faster water evaporation during processing.On the other hand,compared to neat PVA,addition of SOW allowed to significantly decrease the porosity of the produced samples.Despite this,the mechanical properties of the PVA/SOW blends were shown to be lower than those of neat PVA processed analogously.展开更多
This article, based on investigation and analysis, existed anaerobic fermentation equipment, with a view to the production of high-latitude area, pointed out the thought of exploiting efficient anaerobic fermentation ...This article, based on investigation and analysis, existed anaerobic fermentation equipment, with a view to the production of high-latitude area, pointed out the thought of exploiting efficient anaerobic fermentation equipment, including: the settting independent equipment of acidogenic phase and methanogenic phase; the applying conbination of AF and UASB in methanogenic phase; adopting efficient sludge inverse flowing equipment and the technique of flora enrichment, and efficient method of saving energy and thermal retardation; adopting autocontrol which could make the equipment run efficiently and stably.展开更多
The success of solid organ transplant has steadily improved which has led to a unique set of post-transplant issues.The rates of de novo cancer in the solid organ transplant recipient population are higher than those ...The success of solid organ transplant has steadily improved which has led to a unique set of post-transplant issues.The rates of de novo cancer in the solid organ transplant recipient population are higher than those in the general population.There is growing evidence that breast and gynecologic cancers may have a higher mortality rate in post-transplant patients.Cervical and vulvovaginal cancers specifically have a significantly higher mortality in this population.Despite this increased mortality risk,there is currently no consistent standard in screening and identifying these cancers in post-transplant patients.Breast,ovarian and endometrial cancers do not appear to have significantly increased incidence.However,the data on these cancers remains limited.Further studies are needed to determine if more aggressive screening strategies would be of benefit for these cancers.Here we review the cancer incidence,mortality risk and current screening methods associated with breast and gynecologic cancers in the post-solid organ transplant population.展开更多
BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has posed a major public health concern worldwide.Patients with comorbid conditions are at risk of adverse outcomes following COVID-19.Solid organ transplant r...BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has posed a major public health concern worldwide.Patients with comorbid conditions are at risk of adverse outcomes following COVID-19.Solid organ transplant recipients with concurrent immunosuppression and comorbidities are more susceptible to a severe COVID-19 infection.It could lead to higher rates of inpatient complications and mortality in this patient population.However,studies on COVID-19 outcomes in liver transplant(LT)recipients have yielded inconsistent findings.AIM To evaluate the impact of the COVID-19 pandemic on hospital-related outcomes among LT recipients in the United States.METHODS We conducted a retrospective cohort study using the 2019–2020 National Inpatient Sample database.Patients with primary LT hospitalizations and a secondary COVID-19 diagnosis were identified using the International Classi-fication of Diseases,Tenth Revision coding system.The primary outcomes included trends in LT hospitalizations before and during the COVID-19 pandemic.Secondary outcomes included comparative trends in inpatient mortality and transplant rejection in LT recipients.RESULTS A total of 15720 hospitalized LT recipients were included.Approximately 0.8% of patients had a secondary diagnosis of COVID-19 infection.In both cohorts,the median admission age was 57 years.The linear trends for LT hospitalizations did not differ significantly before and during the pandemic(P=0.84).The frequency of in-hospital mortality for LT recipients increased from 1.7% to 4.4% between January 2019 and December 2020.Compared to the pre-pandemic period,a higher association was noted between LT recipients and in-hospital mortality during the pandemic,with an odds ratio(OR)of 1.69[95% confidence interval(CI):1.55-1.84),P<0.001].The frequency of transplant rejections among hospitalized LT recipients increased from 0.2%to 3.6% between January 2019 and December 2020.LT hospitalizations during the COVID-19 pandemic had a higher association with transplant rejection than before the pandemic[OR:1.53(95%CI:1.26-1.85),P<0.001].CONCLUSION The hospitalization rates for LT recipients were comparable before and during the pandemic.Inpatient mortality and transplant rejection rates for hospitalized LT recipients were increased during the COVID-19 pandemic.展开更多
In this editorial,we talk about a compelling case focusing on posterior reversible encephalopathy syndrome(PRES)as a complication in patients undergoing liver transplantation and treated with Tacrolimus.Tacrolimus(FK ...In this editorial,we talk about a compelling case focusing on posterior reversible encephalopathy syndrome(PRES)as a complication in patients undergoing liver transplantation and treated with Tacrolimus.Tacrolimus(FK 506),derived from Streptomyces tsukubaensis,is a potent immunosuppressive macrolide.It inhibits Tcell transcription by binding to FK-binding protein,and is able to amplify glucocorticoid and progesterone effects.Tacrolimus effectively prevents allograft rejection in transplant patients but has adverse effects such as Tacrolimus-related PRES.PRES presents with various neurological symptoms alongside elevated blood pressure,and is primarily characterized by vasogenic edema on neuroimaging.While computed tomography detects initial lesions,magnetic resonance imaging,especially the Fluid-Attenuated Inversion Recovery sequence,is superior for diagnosing cortical and subcortical edema.Our discussion centers on the incidence of PRES in solid organ transplant recipients,which ranges between 0.5 to 5+ACU-,with varying presentations,from seizures to visual disturbances.The case of a 66-year-old male status post liver transplantation highlights the diagnostic and management challenges associated with Tacrolimus-related PRES.Radiographically evident in the parietal and occipital lobes,PRES underlines the need for heightened vigilance among healthcare providers.This editorial emphasizes the importance of early recognition,accurate diagnosis,and effective management of PRES to optimize outcomes in liver transplant patients.The case further explores the balance between the efficacy of immunosuppression with Tacrolimus and its potential neurological risks,underlining the necessity for careful monitoring and intervention strategies in this patient population.展开更多
BACKGROUND Solid organ transplantation is a life-saving intervention for end-stage organ disease.Post-transplant diabetes mellitus(PTDM)is a common complication in solid organ transplant recipients,and significantly c...BACKGROUND Solid organ transplantation is a life-saving intervention for end-stage organ disease.Post-transplant diabetes mellitus(PTDM)is a common complication in solid organ transplant recipients,and significantly compromises long-term survival beyond a year.AIM To perform a systematic review and meta-analysis to estimate incidence of PTDM and compare the effects of the 3 major immunosuppressants on incidence of PTDM.METHODS Two hundred and six eligible studies identified 75595 patients on Tacrolimus,51242 on Cyclosporine and 3020 on Sirolimus.Random effects meta-analyses was used to calculate incidence.RESULTS Network meta-analysis estimated the overall risk of developing PTDM was higher with tacrolimus(OR=1.495%CI:1.0–2.0)and sirolimus(OR=1.8;95%CI:1.5–2.2)than with Cyclosporine.The overall incidence of PTDM at years 2-3 was 17%for kidney,19%for liver and 22%for heart.The risk factors for PTDM most frequently identified in the primary studies were age,body mass index,hepatitis C,and African American descent.CONCLUSION Tacrolimus tends to exhibit higher diabetogenicity in the short-term(2-3 years post-transplant),whereas sirolimus exhibits higher diabetogenicity in the longterm(5-10 years post-transplant).This study will aid clinicians in recognition of risk factors for PTDM and encourage careful evaluation of the risk/benefit of different immunosuppressant regimens in transplant recipients.展开更多
Glucocorticoids(GCs)have been the mainstay of immunosuppressive therapy in solid organ transplantation(SOT)for decades,due to their potent effects on innate immunity and tissue protective effects.However,some SOT cent...Glucocorticoids(GCs)have been the mainstay of immunosuppressive therapy in solid organ transplantation(SOT)for decades,due to their potent effects on innate immunity and tissue protective effects.However,some SOT centers are reluctant to administer GCs long-term because of the various related side effects.This review summarizes the advantages and disadvantages of GCs in SOT.PubMed and Scopus databases were searched from 2011 to April 2021 using search syntaxes covering“transplantation”and“glucocorticoids”.GCs are used in transplant recipients,transplant donors,and organ perfusate solution to improve transplant outcomes.In SOT recipients,GCs are administered as induction and maintenance immunosuppressive therapy.GCs are also the cornerstone to treat acute antibody-and T-cell-mediated rejections.Addition of GCs to organ perfusate solution and pretreatment of transplant donors with GCs are recommended by some guidelines and protocols,to reduce ischemia-reperfusion injury peri-transplant.GCs with low bioavailability and high potency for GC receptors,such as budesonide,nanoparticle-mediated targeted delivery of GCs to specific organs,and combination use of dexamethasone with inducers of immuneregulatory cells,are new methods of GC application in SOT patients to reduce side effects or induce immune-tolerance instead of immunosuppression.Various side effects involving different non-targeted organs/tissues,such as bone,cardiovascular,neuromuscular,skin and gastrointestinal tract,have been noted for GCs.There are also potential drug-drug interactions for GCs in SOT patients.展开更多
BACKGROUND Hepatitis E virus(HEV)infection is underdiagnosed due to the use of serological assays with low sensitivity.Although most patients with HEV recover completely,HEV infection among patients with pre-existing ...BACKGROUND Hepatitis E virus(HEV)infection is underdiagnosed due to the use of serological assays with low sensitivity.Although most patients with HEV recover completely,HEV infection among patients with pre-existing chronic liver disease and organ-transplant recipients on immunosuppressive therapy can result in decompensated liver disease and death.AIM To demonstrate the prevalence of HEV infection in solid organ transplant(SOT)recipients.METHODS We searched Ovid MEDLINE,EMBASE,and the Cochrane Library for eligible articles through October 2020.The inclusion criteria consisted of adult patients with history of SOT.HEV infection is confirmed by either HEV-immunoglobulin G,HEV-immunoglobulin M,or HEV RNA assay.RESULTS Of 563 citations,a total of 22 studies(n=4557)were included in this metaanalysis.The pooled estimated prevalence of HEV infection in SOT patients was 20.2%[95%confidence interval(CI):14.9-26.8].The pooled estimated prevalence of HEV infection for each organ transplant was as follows:liver(27.2%;95%CI:20.0-35.8),kidney(12.8%;95%CI:9.3-17.3),heart(12.8%;95%CI:9.3-17.3),and lung(5.6%;95%CI:1.6-17.9).Comparison across organ transplants demonstrated statistical significance(Q=16.721,P=0.002).The subgroup analyses showed that the prevalence of HEV infection among SOT recipients was significantly higher in middle-income countries compared to high-income countries.The pooled estimated prevalence of de novo HEV infection was 5.1%(95%CI:2.6-9.6)and the pooled estimated prevalence of acute HEV infection was 4.3%(95%CI:1.9-9.4).CONCLUSION HEV infection is common in SOT recipients,particularly in middle-income countries.The prevalence of HEV infection in lung transplant recipients is considerably less common than other organ transplants.More studies examining the clinical impacts of HEV infection in SOT recipients,such as graft failure,rejection,and mortality are warranted.展开更多
Kidney disease after non-kidney solid organ transplantation(NKSOT)is a common post-transplant complication associated with deleterious outcomes.Kidney disease,both acute kidney injury and chronic kidney disease(CKD)al...Kidney disease after non-kidney solid organ transplantation(NKSOT)is a common post-transplant complication associated with deleterious outcomes.Kidney disease,both acute kidney injury and chronic kidney disease(CKD)alike,emanates from multifactorial,summative pre-,peri-and post-transplant events.Several factors leading to kidney disease are shared amongst solid organ transplantation in addition to distinct mechanisms unique to individual transplant types.The aim of this review is to summarize the current literature describing kidney disease in NKSOT.We conducted a narrative review of pertinent studies on the subject,limiting our search to full text studies in the English language.Kidney disease after NKSOT is prevalent,particularly in intestinal and lung transplantation.Management strategies in the peri-operative and post-transplant periods including proteinuria management,calcineurin-inhibitor minimization/sparing approaches,and nephrology referral can counteract CKD progression and/or aid in subsequent kidney after solid organ transplantation.Kidney disease after NKSOT is an important consideration in organ allocation practices,ethics of transplantation.Kidney disease after SOT is an incipient condition demanding further inquiry.While some truths have been revealed about this chronic disease,as we have aimed to describe in this review,continued multidisciplinary efforts are needed more than ever to combat this threat to patient and allograft survival.展开更多
Tens of thousands of people worldwide became infected with syndrome coronavirus-2(SARS-CoV-2).Death rate in general population is about 1%-6%,but this rate rises up to 15%in those with comorbidities.Recent publication...Tens of thousands of people worldwide became infected with syndrome coronavirus-2(SARS-CoV-2).Death rate in general population is about 1%-6%,but this rate rises up to 15%in those with comorbidities.Recent publications showed that the clinical progression of this disease in organ recipients is more destructive,with a fatality rate of up to 14%-25%.We aimed to review the effect of pandemic on various transplantation patients.coronavirus disease 2019(COVID-19)has not only interrupted waiting list patients’lives;it has also impacted transplantation strategies,transplant surgeries and broke donation chains.COVID-19 was directly and indirectly accountable for 73%surplus in mortality of this population as compared to wait listed patients in earlier years.The impact of chronic immunosuppression on outcomes of COVID-19 remains unclear but understanding the immunological mechanisms related to the virus is critically important for the lifetime of transplantation and immune suppressed patients.It is hard to endorse changing anti-rejection therapy,as the existing data appraised is not adequate to advise substituting tacrolimus with cyclosporine during severe COVID-19 disease.展开更多
A novel facile procedure for traceless solid-phase synthesis of 3-substituted isoxazoles in good yields and with excellent purities using polymer-supported vinyl selenide has been developed.
Polystyrene-supported 4-(phenylseleno)morpholine was synthesized and could be used as an efficient ?selenenylating agent for saturated aldehydes. ?Haloaldehydes were prepared by reaction of polystyrene-supported ?sel...Polystyrene-supported 4-(phenylseleno)morpholine was synthesized and could be used as an efficient ?selenenylating agent for saturated aldehydes. ?Haloaldehydes were prepared by reaction of polystyrene-supported ?selenoaldehydes with bromine or sulfuryl chloride in good yield and high purity.展开更多
Reaction of polymer-supported a-selenoaldehydes with Grignard reagents afforded polymer-bound B-hydroxyalkyl selenides, which treated with thionyl chloride and triethylamine leading to (E)-1, 2-disubstituted ethenes i...Reaction of polymer-supported a-selenoaldehydes with Grignard reagents afforded polymer-bound B-hydroxyalkyl selenides, which treated with thionyl chloride and triethylamine leading to (E)-1, 2-disubstituted ethenes in good yield.展开更多
Hepatitis E virus(HEV)infections are generally self-limited.Rare cases of hepatitis E induced fulminant liver failure requiring liver transplantation are reported in the literature.Even though HEV infection is general...Hepatitis E virus(HEV)infections are generally self-limited.Rare cases of hepatitis E induced fulminant liver failure requiring liver transplantation are reported in the literature.Even though HEV infection is generally encountered among developing countries,a recent uptrend is reported in developed countries.Consumption of unprocessed meat and zoonosis are considered to be the likely transmission modalities in developed countries.Renal involvement of HEV generally holds a benign and self-limited course.Although rare cases of cryoglobulinemia are reported in immunocompetent patients,glomerular manifestations of HEV infection are frequently encountered in immunocompromised and solid organ transplant recipients.The spectrum of renal manifestations of HEV infection include prerenal failure,glomerular disorders,tubular and interstitial injury.Kidney biopsy is the gold standard diagnostic test that confirms the pattern of injury.Management predominantly includes conservative approach.Reduction of immunosuppressive medications and ribavirin(for 3-6 mo)is considered among patients with solid organ transplants.Here we review the clinical course,pathogenesis,renal manifestations,and management of HEV among immunocompetent and solid organ transplant recipients.展开更多
基金supported by the National Key Research and Development Program of China[Grant Number 2019YFC1906802].
文摘Methanation is an effective way to efficiently utilize product gas generated from the pyrolysis and gasification of organic solid wastes.To deeply study the heat transfer and mass transfer mechanisms in the reactor,a successful three-dimensional comprehensive model has been established.Multiphase flow behavior and heat transfer mechanisms were investigated under reference working conditions.Temperature is determined by the heat release of the reaction and the heat transfer of the gas-solid flow.The maximum temperature can reach 951 K where the catalyst gathers.In the simulation,changes in the gas inlet velocity and catalyst flow rate were made to explore their effects on CO conversion rate and temperature for optimization purposes.As the inlet gas velocity increases from 2.78 to 4.79 m/s,the CO conversion rate decreases from 81.6%to 72.4%.However,more heat is removed from the reactor,and the temperature rise increases from 78.03 to 113.49 K.When the catalyst flow rate is increased from 7.18 to 17.96 kg/(m^(2)·s),the mass of the catalyst in the reactor is increased from 0.0019 to 0.0042 kg,and the CO conversion rate is increased from 66.8%to 81.5%.However,this increases the maximum temperature in the reactor from 940.0 to 966.4 K.
基金the financial supports provided by the National Key Research and Development Program of China(2019YFC190252).
文摘Combustion of agricultural organic solid waste(AOSW)was an ideal solution for their resource utilization in view of their massive annual production and great potential for reduction of fossil fuel utilization.However,high alkali and alkaline earth metals(AAEMs)content in the feedstock can arose severe fouling and slagging issues and thus prohibiting its vast utilization.In this study,a semi-continuous water washing method was proposed to preliminarily remove AAEMs from agricultural organic solid waste and its effects on the combustion behaviors of washed solid product were investigated.Results showed that the combustion index S were improved to 2.63×10-6,over 68%of the total ashes were removed from the cotton stalk,and 96.3%,89.0%and 74.7%of K,Na and Mg were effectively removed,respectively.Moreover,the softening temperature of low temperature ash from the washed sample was as high as 1450◦C,538◦C higher than the low temperature ash from the original sample;the base acid ratio and fouling index were improved from high slagging and fouling risk(1.7 and 90.8)of the original organic solid waste to low and medium risk(0.4 and 3.5),respectively.All these results signified the contributing effect of proposed semi-continuous water washing method on the combustion of agricultural organic solid waste.In a word,this study provided a promising method for fouling and slagging inhibition during the agricultural organic solid waste combustion.
文摘BACKGROUND De novo malignancy is a leading cause of late morbidity and mortality in liver transplant recipients.Cumulative immunosuppression has been shown to contribute to post-transplant malignancy(PTM)risk.There is emerging evidence on the differential carcinogenic risk profile of individual immunosuppressive drugs,independent of the net effect of immunosuppression.Calcineurin inhibitors such as tacrolimus may promote tumourigenesis,whereas mycophenolic acid(MPA),the active metabolite of mycophenolate mofetil,may limit tumour progression.Liver transplantation(LT)is relatively unique among solid organ transplantation in that immunosuppression monotherapy with either tacrolimus or MPA is often achievable,which makes careful consideration of the risk-benefit profile of these immunosuppression agents particularly relevant for this cohort.However,there is limited clinical data on this subject in both LT and other solid organ transplant recipients.AIM To investigate the relative carcinogenicity of tacrolimus and MPA in solid organ transplantation.METHODS A literature search was conducted using MEDLINE and Embase databases using the key terms“solid organ transplantation”,“tacrolimus”,“mycophenolic acid”,and“carcinogenicity”,in order to identify relevant articles published in English between 1st January 2002 to 11th August 2022.Related terms,synonyms and explosion of MeSH terms,Boolean operators and truncations were also utilised in the search.Reference lists of retrieved articles were also reviewed to identify any additional articles.Excluding duplicates,abstracts from 1230 records were screened by a single reviewer,whereby 31 records were reviewed in detail.Full-text articles were assessed for eligibility based on pre-specified inclusion and exclusion criteria.RESULTS A total of 6 studies were included in this review.All studies were large population registries or cohort studies,which varied in transplant era,type of organ transplanted and immunosuppression protocol used.Overall,there was no clear difference demonstrated between tacrolimus and MPA in de novo PTM risk following solid organ transplantation.Furthermore,no study provided a direct comparison of carcinogenic risk between tacrolimus and MPA monotherapy in solid organ transplantation recipients.CONCLUSION The contrasting carcinogenic risk profiles of tacrolimus and MPA demonstrated in previous experimental studies,and its application in solid organ transplantation,is yet to be confirmed in clinical studies.Thus,the optimal choice of immunosuppression drug to use as maintenance monotherapy in LT recipients is not supported by a strong evidence base and remains unclear.
基金supported by the National Key Research and Development Program of China(Grant No.2019YFC1906401)the Open Project of State Key Laboratory of Urban Water Resources and Environment,Harbin Institute of Technology,China(No.QAK201904).
文摘Antibiotic resistance genes(ARGs)have been diffusely detected in several kinds of organic solid waste,such as livestock manure,sludge,antibiotic fermentation residues,and food waste,thus attracting great attention.Aerobic composting,which is an effective,harmless treatment method for organic solid waste to promote recycling,has been identified to also aid in ARG reduction.However,the effect of composting in removing ARGs from organic solid waste has recently become controversial.Thus,this article summarizes and reviews the research on ARGs in relation to composting in the past 5 years.ARGs in organic solid waste could spread in different environmental media,including soil and the atmosphere,which could widen environmental risks.However,the conventional composting technology had limited effect on ARGs removal from organic solid waste.Improved composting processes,such as hyperthermophilic temperature composting,could effectively remove ARGs,and the HGT of ARGs and the microbial communities are identified as vital influencing factors.Currently,during the composting process,ARGs were mainly affected by three response pathways,(Ⅰ)“Microenvironment-ARGs”;(Ⅱ)“Microenvironment-microorganisms-ARGs”;(Ⅲ)“Microorganisms-horizontal gene transfer-ARGs”,respectively.Response pathway Ⅱ had been studied the most which was believed that microbial community was an important factor affecting ARGs.In response pathway Ⅲ,mainly believed that MGEs played an important role and paid less attention to eARGs.Further research on the role and impact of eARGs in ARGs may be considered in the future.It aims to provide support for further research on environmental risk control of ARGs in organic solid waste.
基金financially supported by the National Key Research and Development Program of China(Grant No.2019YFA0708501)the NSFC Major Research Plan on West-Pacific Earth System Multispheric Interactions(Grant No.92158206)。
文摘The geologic production of abiotic organic compounds has been the subject of increasing scientific attention due to their use in the global carbon flux balance,by chemosynthetic biological communities,and for energy resources.Extensive analysis of methane(CH_(4))and other organics in diverse geologic settings,combined with thermodynamic modelings and laboratory simulations,have yielded insights into the distribution of specific abiotic organic molecules on Earth and the favorable conditions and pathways under which they form.This updated and comprehensive review summarizes published results of petrological,thermodynamic,and experimental investigations of possible pathways for the formation of particular species of abiotic simple hydrocarbon molecules such as CH_(4),and of complex hydrocarbon systems,e.g.,long-chain hydrocarbons and even solid carbonaceous matters,in various geologic processes,distinguished into three classes:(1)pre-to early planetary processes;(2)mantle and magmatic processes;and(3)the gas/water-rock reaction processes in low-pressure ultramafic rock and high-pressure subduction zone systems.We not only emphasize how organics are abiotically synthesized but also explore the role or changes of organics in evolutionary geological environments after synthesis,such as phase transitions or organic-mineral interactions.Correspondingly,there is an urgent need to explore the diversity of abiotic organic compounds prevailing on Earth.
基金by the project POIROT with CUP code B89J17000370008 supported by the MISE(Ministry of Economic Development)of Italy within the European Union’s Horizon 2020 research and innovation program.Eng.Mauro Pollini,Eng.Federica Paladini and Dr.Angelica Panico are kindly acknowledged for bacterial analyses.
文摘This work is aimed at the development of new green composite materials through the incorporation of the solid organic waste(SOW)in a thermoplastic matrix.After being ground,the organic waste was exposed to a sterilization process,though an autoclave cycle,in order to obtain a complete removal of the bacterial activity.The SOW was found to have a high amount of water,about 65-70%,which made uneconomical its further treatment to reduce the water amount.Therefore,a water soluble polymer,poly(vinyl alcohol)(PVA)was chosen in order to produce SOW based blends.However,in order to reduce the viscosity of the PVA/SOW slurry,further amount of water was added.The very low viscosity attained by the water suspension allowed to process the PVA/SOW blends by a pressure-free process,for the production of samples,which were afterwards subjected to physical and mechanical characterization.Flexural tests showed the promising properties of the developed blends.In particular,the relevance of porosity was assessed.Increasing the water amount involved a signification increase of porosity,due to a faster water evaporation during processing.On the other hand,compared to neat PVA,addition of SOW allowed to significantly decrease the porosity of the produced samples.Despite this,the mechanical properties of the PVA/SOW blends were shown to be lower than those of neat PVA processed analogously.
基金Supported by National Natural Sciences Foundation(20040224001)
文摘This article, based on investigation and analysis, existed anaerobic fermentation equipment, with a view to the production of high-latitude area, pointed out the thought of exploiting efficient anaerobic fermentation equipment, including: the settting independent equipment of acidogenic phase and methanogenic phase; the applying conbination of AF and UASB in methanogenic phase; adopting efficient sludge inverse flowing equipment and the technique of flora enrichment, and efficient method of saving energy and thermal retardation; adopting autocontrol which could make the equipment run efficiently and stably.
文摘The success of solid organ transplant has steadily improved which has led to a unique set of post-transplant issues.The rates of de novo cancer in the solid organ transplant recipient population are higher than those in the general population.There is growing evidence that breast and gynecologic cancers may have a higher mortality rate in post-transplant patients.Cervical and vulvovaginal cancers specifically have a significantly higher mortality in this population.Despite this increased mortality risk,there is currently no consistent standard in screening and identifying these cancers in post-transplant patients.Breast,ovarian and endometrial cancers do not appear to have significantly increased incidence.However,the data on these cancers remains limited.Further studies are needed to determine if more aggressive screening strategies would be of benefit for these cancers.Here we review the cancer incidence,mortality risk and current screening methods associated with breast and gynecologic cancers in the post-solid organ transplant population.
文摘BACKGROUND The coronavirus disease 2019(COVID-19)pandemic has posed a major public health concern worldwide.Patients with comorbid conditions are at risk of adverse outcomes following COVID-19.Solid organ transplant recipients with concurrent immunosuppression and comorbidities are more susceptible to a severe COVID-19 infection.It could lead to higher rates of inpatient complications and mortality in this patient population.However,studies on COVID-19 outcomes in liver transplant(LT)recipients have yielded inconsistent findings.AIM To evaluate the impact of the COVID-19 pandemic on hospital-related outcomes among LT recipients in the United States.METHODS We conducted a retrospective cohort study using the 2019–2020 National Inpatient Sample database.Patients with primary LT hospitalizations and a secondary COVID-19 diagnosis were identified using the International Classi-fication of Diseases,Tenth Revision coding system.The primary outcomes included trends in LT hospitalizations before and during the COVID-19 pandemic.Secondary outcomes included comparative trends in inpatient mortality and transplant rejection in LT recipients.RESULTS A total of 15720 hospitalized LT recipients were included.Approximately 0.8% of patients had a secondary diagnosis of COVID-19 infection.In both cohorts,the median admission age was 57 years.The linear trends for LT hospitalizations did not differ significantly before and during the pandemic(P=0.84).The frequency of in-hospital mortality for LT recipients increased from 1.7% to 4.4% between January 2019 and December 2020.Compared to the pre-pandemic period,a higher association was noted between LT recipients and in-hospital mortality during the pandemic,with an odds ratio(OR)of 1.69[95% confidence interval(CI):1.55-1.84),P<0.001].The frequency of transplant rejections among hospitalized LT recipients increased from 0.2%to 3.6% between January 2019 and December 2020.LT hospitalizations during the COVID-19 pandemic had a higher association with transplant rejection than before the pandemic[OR:1.53(95%CI:1.26-1.85),P<0.001].CONCLUSION The hospitalization rates for LT recipients were comparable before and during the pandemic.Inpatient mortality and transplant rejection rates for hospitalized LT recipients were increased during the COVID-19 pandemic.
文摘In this editorial,we talk about a compelling case focusing on posterior reversible encephalopathy syndrome(PRES)as a complication in patients undergoing liver transplantation and treated with Tacrolimus.Tacrolimus(FK 506),derived from Streptomyces tsukubaensis,is a potent immunosuppressive macrolide.It inhibits Tcell transcription by binding to FK-binding protein,and is able to amplify glucocorticoid and progesterone effects.Tacrolimus effectively prevents allograft rejection in transplant patients but has adverse effects such as Tacrolimus-related PRES.PRES presents with various neurological symptoms alongside elevated blood pressure,and is primarily characterized by vasogenic edema on neuroimaging.While computed tomography detects initial lesions,magnetic resonance imaging,especially the Fluid-Attenuated Inversion Recovery sequence,is superior for diagnosing cortical and subcortical edema.Our discussion centers on the incidence of PRES in solid organ transplant recipients,which ranges between 0.5 to 5+ACU-,with varying presentations,from seizures to visual disturbances.The case of a 66-year-old male status post liver transplantation highlights the diagnostic and management challenges associated with Tacrolimus-related PRES.Radiographically evident in the parietal and occipital lobes,PRES underlines the need for heightened vigilance among healthcare providers.This editorial emphasizes the importance of early recognition,accurate diagnosis,and effective management of PRES to optimize outcomes in liver transplant patients.The case further explores the balance between the efficacy of immunosuppression with Tacrolimus and its potential neurological risks,underlining the necessity for careful monitoring and intervention strategies in this patient population.
文摘BACKGROUND Solid organ transplantation is a life-saving intervention for end-stage organ disease.Post-transplant diabetes mellitus(PTDM)is a common complication in solid organ transplant recipients,and significantly compromises long-term survival beyond a year.AIM To perform a systematic review and meta-analysis to estimate incidence of PTDM and compare the effects of the 3 major immunosuppressants on incidence of PTDM.METHODS Two hundred and six eligible studies identified 75595 patients on Tacrolimus,51242 on Cyclosporine and 3020 on Sirolimus.Random effects meta-analyses was used to calculate incidence.RESULTS Network meta-analysis estimated the overall risk of developing PTDM was higher with tacrolimus(OR=1.495%CI:1.0–2.0)and sirolimus(OR=1.8;95%CI:1.5–2.2)than with Cyclosporine.The overall incidence of PTDM at years 2-3 was 17%for kidney,19%for liver and 22%for heart.The risk factors for PTDM most frequently identified in the primary studies were age,body mass index,hepatitis C,and African American descent.CONCLUSION Tacrolimus tends to exhibit higher diabetogenicity in the short-term(2-3 years post-transplant),whereas sirolimus exhibits higher diabetogenicity in the longterm(5-10 years post-transplant).This study will aid clinicians in recognition of risk factors for PTDM and encourage careful evaluation of the risk/benefit of different immunosuppressant regimens in transplant recipients.
文摘Glucocorticoids(GCs)have been the mainstay of immunosuppressive therapy in solid organ transplantation(SOT)for decades,due to their potent effects on innate immunity and tissue protective effects.However,some SOT centers are reluctant to administer GCs long-term because of the various related side effects.This review summarizes the advantages and disadvantages of GCs in SOT.PubMed and Scopus databases were searched from 2011 to April 2021 using search syntaxes covering“transplantation”and“glucocorticoids”.GCs are used in transplant recipients,transplant donors,and organ perfusate solution to improve transplant outcomes.In SOT recipients,GCs are administered as induction and maintenance immunosuppressive therapy.GCs are also the cornerstone to treat acute antibody-and T-cell-mediated rejections.Addition of GCs to organ perfusate solution and pretreatment of transplant donors with GCs are recommended by some guidelines and protocols,to reduce ischemia-reperfusion injury peri-transplant.GCs with low bioavailability and high potency for GC receptors,such as budesonide,nanoparticle-mediated targeted delivery of GCs to specific organs,and combination use of dexamethasone with inducers of immuneregulatory cells,are new methods of GC application in SOT patients to reduce side effects or induce immune-tolerance instead of immunosuppression.Various side effects involving different non-targeted organs/tissues,such as bone,cardiovascular,neuromuscular,skin and gastrointestinal tract,have been noted for GCs.There are also potential drug-drug interactions for GCs in SOT patients.
文摘BACKGROUND Hepatitis E virus(HEV)infection is underdiagnosed due to the use of serological assays with low sensitivity.Although most patients with HEV recover completely,HEV infection among patients with pre-existing chronic liver disease and organ-transplant recipients on immunosuppressive therapy can result in decompensated liver disease and death.AIM To demonstrate the prevalence of HEV infection in solid organ transplant(SOT)recipients.METHODS We searched Ovid MEDLINE,EMBASE,and the Cochrane Library for eligible articles through October 2020.The inclusion criteria consisted of adult patients with history of SOT.HEV infection is confirmed by either HEV-immunoglobulin G,HEV-immunoglobulin M,or HEV RNA assay.RESULTS Of 563 citations,a total of 22 studies(n=4557)were included in this metaanalysis.The pooled estimated prevalence of HEV infection in SOT patients was 20.2%[95%confidence interval(CI):14.9-26.8].The pooled estimated prevalence of HEV infection for each organ transplant was as follows:liver(27.2%;95%CI:20.0-35.8),kidney(12.8%;95%CI:9.3-17.3),heart(12.8%;95%CI:9.3-17.3),and lung(5.6%;95%CI:1.6-17.9).Comparison across organ transplants demonstrated statistical significance(Q=16.721,P=0.002).The subgroup analyses showed that the prevalence of HEV infection among SOT recipients was significantly higher in middle-income countries compared to high-income countries.The pooled estimated prevalence of de novo HEV infection was 5.1%(95%CI:2.6-9.6)and the pooled estimated prevalence of acute HEV infection was 4.3%(95%CI:1.9-9.4).CONCLUSION HEV infection is common in SOT recipients,particularly in middle-income countries.The prevalence of HEV infection in lung transplant recipients is considerably less common than other organ transplants.More studies examining the clinical impacts of HEV infection in SOT recipients,such as graft failure,rejection,and mortality are warranted.
文摘Kidney disease after non-kidney solid organ transplantation(NKSOT)is a common post-transplant complication associated with deleterious outcomes.Kidney disease,both acute kidney injury and chronic kidney disease(CKD)alike,emanates from multifactorial,summative pre-,peri-and post-transplant events.Several factors leading to kidney disease are shared amongst solid organ transplantation in addition to distinct mechanisms unique to individual transplant types.The aim of this review is to summarize the current literature describing kidney disease in NKSOT.We conducted a narrative review of pertinent studies on the subject,limiting our search to full text studies in the English language.Kidney disease after NKSOT is prevalent,particularly in intestinal and lung transplantation.Management strategies in the peri-operative and post-transplant periods including proteinuria management,calcineurin-inhibitor minimization/sparing approaches,and nephrology referral can counteract CKD progression and/or aid in subsequent kidney after solid organ transplantation.Kidney disease after NKSOT is an important consideration in organ allocation practices,ethics of transplantation.Kidney disease after SOT is an incipient condition demanding further inquiry.While some truths have been revealed about this chronic disease,as we have aimed to describe in this review,continued multidisciplinary efforts are needed more than ever to combat this threat to patient and allograft survival.
文摘Tens of thousands of people worldwide became infected with syndrome coronavirus-2(SARS-CoV-2).Death rate in general population is about 1%-6%,but this rate rises up to 15%in those with comorbidities.Recent publications showed that the clinical progression of this disease in organ recipients is more destructive,with a fatality rate of up to 14%-25%.We aimed to review the effect of pandemic on various transplantation patients.coronavirus disease 2019(COVID-19)has not only interrupted waiting list patients’lives;it has also impacted transplantation strategies,transplant surgeries and broke donation chains.COVID-19 was directly and indirectly accountable for 73%surplus in mortality of this population as compared to wait listed patients in earlier years.The impact of chronic immunosuppression on outcomes of COVID-19 remains unclear but understanding the immunological mechanisms related to the virus is critically important for the lifetime of transplantation and immune suppressed patients.It is hard to endorse changing anti-rejection therapy,as the existing data appraised is not adequate to advise substituting tacrolimus with cyclosporine during severe COVID-19 disease.
基金We thank the National Natural Science Foundation of China(No.20562005)NSF of Jiangxi Province for financial support.
文摘A novel facile procedure for traceless solid-phase synthesis of 3-substituted isoxazoles in good yields and with excellent purities using polymer-supported vinyl selenide has been developed.
文摘Polystyrene-supported 4-(phenylseleno)morpholine was synthesized and could be used as an efficient ?selenenylating agent for saturated aldehydes. ?Haloaldehydes were prepared by reaction of polystyrene-supported ?selenoaldehydes with bromine or sulfuryl chloride in good yield and high purity.
基金Project 29932020 was supported by the National Natural Science Foundation of China.
文摘Reaction of polymer-supported a-selenoaldehydes with Grignard reagents afforded polymer-bound B-hydroxyalkyl selenides, which treated with thionyl chloride and triethylamine leading to (E)-1, 2-disubstituted ethenes in good yield.
文摘Hepatitis E virus(HEV)infections are generally self-limited.Rare cases of hepatitis E induced fulminant liver failure requiring liver transplantation are reported in the literature.Even though HEV infection is generally encountered among developing countries,a recent uptrend is reported in developed countries.Consumption of unprocessed meat and zoonosis are considered to be the likely transmission modalities in developed countries.Renal involvement of HEV generally holds a benign and self-limited course.Although rare cases of cryoglobulinemia are reported in immunocompetent patients,glomerular manifestations of HEV infection are frequently encountered in immunocompromised and solid organ transplant recipients.The spectrum of renal manifestations of HEV infection include prerenal failure,glomerular disorders,tubular and interstitial injury.Kidney biopsy is the gold standard diagnostic test that confirms the pattern of injury.Management predominantly includes conservative approach.Reduction of immunosuppressive medications and ribavirin(for 3-6 mo)is considered among patients with solid organ transplants.Here we review the clinical course,pathogenesis,renal manifestations,and management of HEV among immunocompetent and solid organ transplant recipients.