Internal transcribed spacer sequencing to explore the intrinsic composition of fungal communities in fungal esophagitis

BACKGROUND Fungal esophagitis(FE)is caused by fungal invasion of the esophageal mucosa.Under endoscopy,the esophageal mucosa shows edema,congestion,erosion,and ulceration,and bleeds easily when touched,and the surface of the mucosa is covered with small white spots like"bean curd residue".Clinical cases showing typical FE under endoscopic imaging but negative esophageal mucosal brush(referred to as suspected FE)have increased the difficulty and challenge of clinical diagnosis and treatment.At present,the esophageal fungal flora of suspected case has not been thoroughly studied.AIM To characterize the fungal flora in FE,suspected FE,and the esophageal normal controls(NCs),and to identify marker species to improve detection of FE.METHODS This was a case-control study.A total of 19 patients with FE,16 with suspected FE,and 10 NCs were selected by endoscopy.The esophageal cell brush samples of each group were sequenced by internal transcribed spacer(ITS)1 and analyzed by bioinformatics.RESULTS In FE and suspected FE patients,species richness,species diversity and species evenness,as measured by the Chao1 index,Shannon index and Pielou index,were lower than in the NCs,and the comparison between the FE and NCs was the most significant(P<0.05).Compared with the NCs,the relative abundance of Candida in FE and suspected FE patients was significantly increased(P<0.001),while the relative abundance of Yarrowia was significantly decreased(P<0.05).Moreover,Yarrowia abundance in the FE group was significantly lower than in the NCs and suspected FE groups(P<0.001).The area under the curve for Candida in FE and suspected FE patients was 99.5%(P<0.05)and 81.3%(P<0.05),respectively.Finally,compared with FE patients,the relative abundance of Ascomycota and Candida in the esophageal flora of suspected FE patients was decreased,while the relative abundance of Yarrowia,Thermomyces and Pichia was increased.CONCLUSION ITS showed that composition of the fungal community was similar in the FE and suspected FE groups.ITS can be used as an auxiliary diagnostic method for FE and provide a theoretical basis for follow-up diagnosis and treatment.

Diverse responses of fungal functional groups to desertification in forest soils of Pinus densata on the Chinese Tibetan plateau

Rapid increase in desertification is an environ-mental concern,especially for the health and sustainabil-ity of ecosystems in changing climates.How ecosystems respond to such changes may be partially understood by studying interactions and performance of critically impor-tant groups such as soil fungi functional groups.This study investigated variations in diversities of three soil fungi functional guilds(saprotrophic,symbiotic,pathogenic)and influencing abiotic factors in a Pinus densata forest on the southeast Tibetan Plateau where desertification is intense.The results indicate desertification significantly decreased the proportion of dominant fungal guild-symbiotic fungi(mean relative abundance decreasing from 97.0%to 68.3%),in contrast to saprotrophic fungi(increasing from 2.7%to 25.7%)and pathogenic(from 0.3%to 5.9%).Soil pH had the most significant impact on fungal community structure and negatively correlated with symbiotic fungal richness,which was significantly lower in arid soils,and positively correlated with saprotrophic and pathogenic fungal alpha-diversity,which were abundant.Different community struc-tures and regulators of the three fungi communities were observed,with pH,total phosphorus and ammonium(NH_(4)^(+))as the main determinants.This study links the biotic and abi-otic components during desertification and the interactions between them,and may be used as indicators of ecosystem health and for amendments to mitigate the effects of a chang-ing climate.

Contribution to the Study of Fungal Strains Contaminating Peanut Pastes in Bangui (Central African Republic)

Introduction: Peanut pastes are food products resulting from artisanal or industrial processing, used in cooking in Africa in general and in Central African Republic in particular. These peanut pastes are often contaminated by molds and filamentous fungi involved in the degradation of hygienic and organoleptic or even toxicological quality. This study aims to determine the epidemiological profile of molds contaminating peanut pastes sold on the Central African market. Methodology: This was a cross-sectional study carried out from June to September 2023. Samples of peanut pastes sold on Central African market were taken and analyzed at the National Laboratory of Clinical Biology and Public Health using the conventional microbiology method according to ISO 7954 standards. The data obtained were collected in the ODK 2023.3.1 application and analyzed with the Epi Info 7 software. A multivariate analysis by logistic regression, Ficher’s exact test, and chi2 at the 5% threshold (p Penicillium sp.;11.25% of Mucor sp.;10.63% of Aspergillus terrei;3.13% of Aspergillus niger;1.25% of Aspergillus medullans;28.13% of Aspergillus flavus;2.50% of Aspergillus fumigatus. Peanut pastes stored beyond three days were more contaminated (94.19%). Conclusion: The results of this study made it possible to highlight strains of mold that impact the hygienic and organoleptic quality of peanut pastes sold at the Central African market. Most of the isolated strains were the Aspergillus flavus species which is recognized by its toxigenic effects. This species is much more incriminated in the contamination of foodstuffs with the production of the toxin which causes underlying pulmonary pathologies in humans.

Advances in Drug Treatment of Fungal Keratitis

Fungal keratitis is an important cause of corneal blindness in China, accounting for 45% of infectious keratitis. The main pathogenic bacteria include yeast, filamentous bacteria and nearly 100 kinds of fungi, which are difficult to diagnose, difficult to treat and poor prognosis. When the infected fungal strains have strong virulence and poor drug sensitivity, it is easy to prolong the disease. Once the fungal infection involves the whole limbus and reaches the whole layer of the cornea, it will be followed by intraocular tissue infection such as anterior chamber, lens and vitreous body. When the infection is difficult to control and the visual function is seriously damaged, the enucleation of eye contents has to be performed, which causes irreversible harm to the patient’s appearance and physical and mental health. Therefore, in order to gain greater hope for the vision of patients with fungal keratitis, In recent years, with the continuous progress of clinical medicine and microbiological diagnostics, the treatment methods of fungal keratitis have been constantly updated. This article will briefly review the new progress in drug and surgical treatment of fungal keratitis in recent years to provide patients with better visual prognosis. .

Global Burden of Fungal Infections and Antifungal Resistance from 1961 to 2024: Findings and Future Implications

Background: Antifungal resistance (AFR) is a global public health problem with devastating effects, especially among immunocompromised individuals. Addressing AFR requires a One Health approach including Antifungal Stewardship (AFS). This study aimed to comprehensively review global studies published on fungal infections and AFR and to recommend solutions to address this growing problem. Materials and Methods: This was a narrative review that was conducted using published papers on fungal infections, AFR, and AFS between January 1961 and March 2024. The literature was searched using PubMed, Google Scholar, Web of Science, and EMBASE. Results: This found that there has been an increase in fungal infections globally, especially among immunocompromised patients. Due to this increase in fungal infections, there has been a proportionate increase in the use of antifungal agents to prevent and treat fungal infections. This increased use of antifungal agents has worsened the problem of AFR contributing to increased morbidity and mortality. Globally, fungal infections have contributed to 150 million infections annually and 1.7 million deaths per year. By the year 2023, over 3.8 million people died from fungal infections. Addressing AFR remains a challenge because the treatment of antifungal-resistant infections is difficult. Finally, the treatment of fungal infections is a global challenge exacerbated by the limited number of antifungal agents to treat invasive fungal infections. Conclusion: The results of this study indicated that fungal infections and AFR are prevalent across humans, animals, agriculture, and the environment. Addressing this problem requires the provision of solutions such as improving the awareness of AFR, conducting further research on the discovery of new antifungal agents, and implementing AFS programs. If this global problem is not addressed, the morbidity and mortality associated with AFR will continue to rise in the future.

Comparison of fungal vs bacterial infections in the medical intensive liver unit:Cause or corollary for high mortality?

BACKGROUND Due to development of an immune-dysregulated phenotype,advanced liver disease in all forms predisposes patients to sepsis acquisition,including by opportunistic pathogens such as fungi.Little data exists on fungal infection within a medical intensive liver unit(MILU),particularly in relation to acute on chronic liver failure.AIM To investigate the impact of fungal infections among critically ill patients with advanced liver disease,and compare outcomes to those of patients with bacterial infections.METHODS From our prospective registry of MILU patients from 2018-2022,we included 27 patients with culture-positive fungal infections and 183 with bacterial infections.We compared outcomes between patients admitted to the MILU with fungal infections to bacterial counterparts.Data was extracted through chart review.RESULTS All fungal infections were due to Candida species,and were most frequently blood isolates.Mortality among patients with fungal infections was significantly worse relative to the bacterial cohort(93%vs 52%,P<0.001).The majority of the fungal cohort developed grade 2 or 3 acute on chronic liver failure(ACLF)(90%vs 64%,P=0.02).Patients in the fungal cohort had increased use of vasopressors(96%vs 70%,P=0.04),mechanical ventilation(96%vs 65%,P<0.001),and dialysis due to acute kidney injury(78%vs 52%,P=0.014).On MILU admission,the fungal cohort had significantly higher Acute Physiology and Chronic Health Evaluation(108 vs 91,P=0.003),Acute Physiology Score(86 vs 65,P=0.003),and Model for End-Stage Liver Disease-Sodium scores(86 vs 65,P=0.041).There was no significant difference in the rate of central line use preceding culture(52%vs 40%,P=0.2).Patients with fungal infection had higher rate of transplant hold placement,and lower rates of transplant;however,differences did not achieve statistical significance.CONCLUSION Mortality was worse among patients with fungal infections,likely attributable to severe ACLF development.Prospective studies examining empiric antifungals in severe ACLF and associations between fungal infections and transplant outcomes are critical.

Impact of Vegetation Restoration on Soil Fungal Community Structure in Karst Rocky Desertification Areas

In this paper,managed forest(MF)and natural forest(NF)in the Huajiang Demonstration Zone of Guanling,Guizhou were selected as research objects,and cropland(CL)was taken as control.High-throughput sequencing technology was used to study the characteristics of fungal community composition and species diversity in the surface(0-10 cm)soil of each restoration measure,in order to reveal the dominant soil fungal groups and fungal community composition in karst rocky desertification areas,which was conducive to a more comprehensive understanding of the soil conditions of different vegetation restoration measures.Research has shown that vegetation restoration significantly affected the diversity of soil fungal community,with significant increases in Sob index,Ace index,and Chao index.The vegetation restoration has significantly changed the composition of fungal community.The dominant fungi in the CL topsoil are Sordariomycetes(62.28%),Dothideomycetes(12.34%),and Eurotiomycetes(9.12%);the dominant fungi in the MF soil are Sordariomycetes(45.05%),Dothideomycetes(14.74%),and Mortierellomycetes(10.40%);the dominant fungi in the NF soil are unclassified fungal community(26.38%),Sordariomycetes(19.78%),and Agaricomycetes(13.82%).Vegetation restoration has changed the key fungal groups in the soil.Sordariomycetes,Fusarium,and Setophoma are the key dominant fungal groups in CL soil;Dioszegia is key dominant fungal group in MF soil;c_unclassified_k_Fungi,p_unclassified_k_Fungi,o_unclassified_k_Fungi,f_unclassified_k_Fungi,g_unclassified_k_Fungi,Teichospora,and Diaporthe are key dominant fungal groups in NF soil.

Polyphenol from foxtail millet bran alleviates experimental colitis in mice by remodulating intestinal fungal community

Inflammatory bowel disease(IBD)is a chronic relapsing-remitting systemic disease of the gastrointestinal tract,characterized by an inflammatory process.Gut mycobiota community dysbiosis has been reported that is closely related to the development of IBD.Our previous findings indicated that polyphenol of the inner shell(BPIS)from foxtail millet bran could restore the gut microbiome and inhibit the progress of colorectal cancer(CRC).In the present study,we studied the anti-inflammatory potential of BPIS in the dextran sodium sulfate(DSS)-induced mouse colitis model.Data suggested that BPIS alleviated experimental colitis by restoring body weight,colonic length and protecting the epithelial architecture from damage by DSS.Moreover,we found that BPIS strengthened the gut barrier function and inhibited the activation of Wnt1/β-catenin pathway.Gene sequence analysis indicated that BPIS remodeled the overall structure of the gut mycobiota from colitis mice toward that of the normal counterparts,including 1 phylum and 9 genera.Interestingly,BPIS significantly increased the abundance of Aspergillus ruber.It further verified that BPIS significantly promoted the growth of A.ruber in vitro.Collectively,BPIS has great potential to develop into an effective against IBD drug.

Candidemia chronicles:Retrospective analysis of candidemia epidemiology,species distribution,and antifungal susceptibility patterns in Bahrain

BACKGROUND Invasive fungal infections,particularly candidemia,pose significant clinical challenges globally.Understanding local epidemiology,species distribution,and antifungal susceptibility patterns is crucial for effective management despite regional variations.AIM To investigate the epidemiology,species distribution,antifungal susceptibility patterns,and associated risk factors of candidemia among patients in Bahrain from 2021 to 2023.METHODS This retrospective study analyzed demographic data,Candida species distribution,antifungal susceptibility profiles,and risk factors among candidemia patients treated at a tertiary care hospital in Bahrain over three years.Data was collected from medical records and analyzed using descriptive statistics.RESULTS A total of 430 candidemia cases were identified.The mean age of patients was 65.7 years,with a mortality rate of 85.5%.Candida albicans(C.albicans)was the most common species,followed by Candida parapsilosis,Candida tropicalis(C.tropicalis),and emerging multidrug-resistant Candida auris(C.auris).Antifungal susceptibility varied across species,with declining susceptibility to azoles observed,particularly among C.albicans and C.tropicalis.Major risk factors included central venous catheters,broad-spectrum antibiotics,and surgical procedures.CONCLUSION This study highlights the substantial burden of candidemia among older adults in Bahrain,characterized by diverse Candida species.It also concerns levels of antifungal resistance,notably in C.auris.The findings underscore the importance of local epidemiological surveillance and tailored treatment strategies to improve outcomes and mitigate the spread of multidrug-resistant Candida species.Future research should focus on molecular resistance mechanisms and optimizing therapeutic approaches to address this growing public health concern.

Prevalence of Bacterial and Fungal Infected Chronic Leg Ulcers at a Teaching Hospital in Ghana

Background: Chronic ulcers are responsible for considerable morbidity and significantly contribute to the escalation in the cost of health care. Chronic leg ulcers (CLUs) are susceptible to microbial infections and serious complications such as tissue necrosis and osteomyelitis, can result without the timely control of infections. Recent studies have also reported an increase in the association of fungal infections with chronic non-healing ulcers. Aim: To determine the prevalence of bacterial and fungal infections among patients reporting with chronic leg ulcers in participants without co-morbidities. Methods: A prospective cross-sectional study was conducted among patients with chronic leg ulcers at the National Reconstructive Plastic Surgery and Burns Centre, Korle-Bu Teaching Hospital (NRPS/BC-KBTH) and those who consented were enrolled. Characteristics of the wound as well as micro-organisms cultured from wound swabs were recorded. Results: A total of 50 participants were enrolled for the study with the mean (SD) age of 40.7 (10.7) years. Eighty percent of the participants presented with post traumatic leg ulcers with 80% being artisans and traders in the age group 31 - 50 years. There was no statistically significant association between sex and the organism cultured for post traumatic and cellulitis (p-value > 0.05). The prevalence of bacterial and fungal infection was 79.3% and 20.7% respectively. Pseudomonas species was the most isolated bacteria (61.5%) while Aspergillus niger was the most isolated fungi (41%). Conclusion: From this study, fungal infections should be included in managing chronic leg ulcers, especially among artisans, famers and gardeners even though there was a significantly higher burden of bacterial infections.

Proposed computed tomography severity index for the evaluation of invasive fungal sinusitis:Preliminary results

BACKGROUND Invasive fungal sinusitis(IFS)can present as a mild disease to life-threatening infection.A recent surge in cases was seen due to the coronavirus disease 2019(COVID-19)pandemic.Many patients require surgical debridement and hence imaging[contrast-enhanced computed tomography(CECT)of the paranasal sinuses(PNS)]to document the extent of the disease.However,there was no scoring system using CECT to describe the severity of IFS.This study proposes a computed tomography(CT)severity index(CTSI)to describe the severity of rhino-orbital-cerebral involvement in symptomatic COVID-19 patients and hypothesizes that higher CTSI correlates with disease severity and thus slow response/non-response to treatment.AIM To propose a scoring system using CECT to describe the severity of IFS and correlate it with clinical outcomes.METHODS A prospective study on 66 COVID-19 positive patients with CECT PNS done for IFS was performed.Split-bolus single-phase CT technique was used.Based on the extent of involvement,a CTSI was designed.Disease in four major subsite areas was assessed.Each subsite involvement was given points according to this model and then summated.Based on the final summated CTSI,the disease was classified as mild,moderate,or severe.Two subsets were subsequently analyzed including survival and death;and responders and non-responders.RESULTS The study cohort was 66 COVID-19-positive patients with suspected IFS with a median age of 48.5 years.Mild disease was noted in 34(51.52%),moderate in 28(42.42%),and severe disease in 4(6.06%)patients.There was a significant association of mortality and poor clinical response(P=0.02)with disease bilaterality.Laterality and CTSI were significant predictors of response to treatment.The mean CTSI of responders was 6.3,of non-responders was 12.9 and the response to treatment was significantly associated with CTSI(t-test,P<0.001).Receiver operating characteristic curve analysis(Liu method)to distinguish between responders and non-responders showed that the cut-off value for CTSI of 11 had a sensitivity of 78.26%and a specificity of 95.35%to predict response assessment.CONCLUSION CTSI can help in quantification of the disease burden,mapping out disease extent,triaging patients,and response assessment;especially patients with underlying comorbidities.A higher score would alert the clinician to initiate aggressive treatment,as severe disease correlates with slow response/non-response to the treatment.

犬粮食品生物安全风险分析

近些年,宠物狗的食品营养品质与安全受到重视。然而,犬粮安全问题时有发生,尤其是微生物方面,引起了宠物行业和养宠爱好者的高度关注。为全面了解犬粮的质量和安全性,本试验对市场上的四种主粮食品(膨化粮、鲜肉粮、低温烘焙粮和益生菌粮)进行了生物安全指标分析,包括重金属、微生物数量、有害病原菌、生物胺、内毒素和真菌毒素等。研究结果显示:四种主粮食品的重金属、细菌总数、有害病原菌和真菌毒素都符合全价宠物食品犬粮GB/T31216-2014的限量标准,但多数样本检测出呕吐毒素。不同类型犬粮均检测出生物胺和内毒素,生产工艺对该方面的指标有一定影响,尤其是低温烘焙粮和益生菌粮,这些指标需引起高度重视。通过对生物安全指标进行分析发现,微生物产生的内毒素、生物胺和真菌毒素是犬粮食品潜在的安全风险。本研究为行业的健康发展和消费者获取高品质、安全的犬粮提供了指导。

Effects of Fungal Elicitors on Cell Growth and Artemisinin Accumulation in Hairy Root Cultures of Artemisia annua

The artemisinin accumulation in the hairy root cultures of Artemisia annua L. was enhanced via a treatment of three fungal elicitors separately ( Verticillium dahliae Kleb., Rhizopus stolonifer (Ehrenb. ex Fr.) Vuill and Colletotrichum dematium (Pers.) Grove). Among these three elicitors, V. dahliae had the highest inducing efficiency, but none of them manifests any noticeable effects on the cell growth of the hairy root cultures. The artemisinin content of the hairy root cultures treated with V. dahliae elicitor was 1.12 mg/g DW, which was 45% higher than the control (0.77 mg/g DW). The results showed that elicitation was dependent on the elicitor concentration, the incubation period and the physiological stage at which the hairy root cultures were treated. In addition, the authors found that for V. dahliae , the optimum concentration was 0.4 mg carbohydrate per millilitre medium, the strongest response of A. annua hairy root cultures to the elicitation was at the late exponential growth stage, and the highest artemisinin content of the hairy root cultures was on the 4th day post treatment.

眼科微针药物递送的研究进展

由于眼部存在生理屏障(包括外眼屏障和内眼屏障),使得常规眼科用药(滴眼液、眼膏、凝胶等)的生物利用度低,且到达眼后节困难。玻璃体注射虽然能使药物到达眼后节,但存在感染、损伤以及患者耐受性差等缺点。眼用微针突破了眼内外屏障,使药物能够精准到达治疗部位并能持续释放,很大程度地避免了眼内感染和损伤,提高了药物的生物利用度,作为眼部药物输送工具存在着明显的优势。眼用微针按使用方法可分为空心微针、可溶性微针和涂层微针。3种微针各具优势,在治疗细菌性和真菌性角膜炎、青光眼、渗出性老年性黄斑变性、糖尿病性黄斑水肿、非感染性葡萄膜炎、角膜新生血管甚至脉络膜黑色素瘤等疾病方面都有令人满意的表现。

卡氏枝孢霉感染二例并文献复习

2例患者均为具有外伤史的老年农民,皮损表现为无症状增生性斑块。组织病理学检查示典型的硬壳小体。真菌培养鉴定为卡氏枝孢霉(Cladophialophora carrionii)。给予口服伊曲康唑200 mg每日两次,外用夫西地酸乳膏和硝酸舍他康唑乳膏。1个月后患者皮损改善。本文通过文献复习,发现中国卡氏枝孢霉感染发病人群主要为中老年(平均年龄53.7岁),50%患者有外伤史。受累部位以上肢最为多见,斑块是最常见的皮损形态,平均病程约为5.4年,由于缺乏自觉症状,患者往往推迟就诊,可能导致感染蔓延,引起畸残。卡氏枝孢霉对抗真菌药物敏感。

基因多态性对侵袭性真菌感染患者伏立康唑血药浓度影响的Meta分析

目的 评价基因多态性对侵袭性真菌感染患者伏立康唑(VRZ)血药谷浓度(c_(min))的影响。方法 检索the Cochrane Library、Embase、PubMed、Web of Science、中国生物医学文献数据库、中国知网、维普网和万方数据,收集基因多态性与VRZ c_(min)相关的文献,检索时间为建库至2024年4月。筛选文献,提取资料,评价文献质量后,使用R 4.3.2软件进行Meta分析。结果 共纳入21篇文献,共计2 454例患者。Meta分析结果显示,CYP2C19 IM型、PM型患者的VRZ c_(min)均显著高于EM型,而IM型显著低于PM型(P<0.01);CYP2C9 rs1057910 AA型患者的VRZ c_(min)显著高于AC/CC型,CYP3A5 rs776746 CC型患者的VRZ c_(min)显著高于TT型(P<0.01);POR rs10954732 GG型患者的VRZ c_(min)显著高于GA型和AA型,POR rs1057868 CT型患者的VRZ c_(min)显著低于TT型(P<0.01);ABCB1 rs1045642 CC型患者的VRZ c_(min)显著高于TT型(P<0.05);NR1I2 rs2472677 CT型患者的VRZ c_(min)显著高于TT型,NR1I2 rs7643645 AA型患者的VRZ c_(min)显著高于AG型(P<0.05);ABCC2 rs717620 CC型患者的VRZ c_(min)均显著低于CT型和TT型,且CT型显著低于TT型(P<0.01)。结论 CYP2C19、CYP2C9rs1057910、CYP3A5rs776746、PORrs10954732、ABCB1rs1045642、NR1I2 rs7643645突变等位基因均可导致VRZ血药浓度降低,ABCC2 rs717620突变等位基因则可导致VRZ血药浓度升高。

红三叶真菌性病害及其防治的研究进展

红三叶是一种重要的豆科牧草及绿肥作物,病害是限制其生产和利用的重要因素。本文整理了国内外报道的红三叶真菌性病害的种类、病原、分布及主要的防治技术。截至2023年,世界范围内报道的红三叶真菌性病害有白粉病、锈病、根/冠腐病及各类叶斑病等,可划分为23个不同种类,病原真菌共36种,分布于18个国家。对红三叶真菌性病害的研究主要集中在白粉病、菌核病、根腐病、炭疽病和匍柄霉叶斑病。此外,国内外研究还在红三叶种子上检测出数种种子携带病原真菌,如匍柄霉和单胞锈菌等。后续应关注影响我国红三叶生产的主要真菌病害,在确定病原真菌的基础上,加深对病原真菌发生规律的研究,制定出有效的防治策略。

424例地中海贫血患儿异基因造血干细胞移植后继发侵袭性真菌病临床分析

目的探讨儿童输血依赖型地中海贫血(TDT)患者接受异基因造血干细胞移植(allo-HSCT)后继发侵袭性真菌病(IFD)的临床特征及危险因素。方法回顾性分析2021年1月至2022年12月共424例接受allo-HSCT的TDT患儿的临床资料,分析allo-HSCT后IFD发生的影响因素。结果共424例患儿纳入研究,其中男261例(61.6%)、女163例(38.4%),中位年龄8.0(5.0~11.0)岁;单倍体移植278例,亲缘全/良好相合移植116例,无关全/良好相合移植30例;所有移植患儿均进行抗真菌初级预防。IFD共发生30例(7.1%),男20例、女10例,临床诊断25例(83.3%)、确诊5例(16.7%),中位发生时间为移植后39.0(23.5~85.8)天;肺部为最常见的感染部位(24例,80.0%),咳嗽(15例,50.0%)和发热(10例,33.3%)为主要症状,肺部影像学以不典型表现为主(14例,46.7%)。主要真菌病原为曲霉菌(19例,63.3%)。17例(56.7%)检出合并感染,以合并病毒感染多见。中位随访时间为16.0(9.0~21.8)个月,OS率为(99.3±0.01)%。非IFD组与IFD组OS率分别为(99.7±0.003)%和(93.3±0.06)%,两组间差异有统计学意义(P<0.001)。二分类多因素logistic回归显示植入不良或植入失败、有急性移植物抗宿主病史、非泊沙康唑预防是IFD发生的危险因素(P<0.05)。结论接受allo-HSCT后经初级真菌预防的TDT儿童IFD发生率低。IFD与较高的死亡风险相关。植入不良或植入失败、有急性移植物抗宿主病史和未使用泊沙康唑预防的患儿发生IFD的风险更高。

菊苣叶内生真菌的分离及其抗植物病原菌活性分析

采用组织分离法从菊苣(Cichorium intybus Linn.)叶分离内生真菌,结合平板对峙法筛选对9种常见植物病原菌具有拮抗活性的内生真菌,联合形态学和分子生物学进行鉴定,并检测活性内生真菌发酵产物的抑菌效果。结果显示:从菊苣叶中分离得到24株内生真菌,筛选到1株对9种植物病原菌均有较好拮抗活性的内生真菌菌株CIY4,鉴定其为链格孢属(Alternaria Nees)的损毁链格孢(Alternaria destruens)。500μg·mL^(-1)的菌株CIY4发酵产物对水稻纹枯病菌(Rhizoctonia solani J.G.Kühn)的抑制率达到86.31%,其后依次为油菜菌核病菌(Sclerotinia sclerotiorum Lib.)(85.45%)、枸杞炭疽病菌(Colletotrichum acutatum J.H.Simmonds)(77.87%)、橡胶树炭疽病菌(Colletotrichum gloeosporioides Penz.)(71.12%),对其他植物病原菌的抑制率低于70%。本研究首次分离筛选了菊苣叶中内生真菌菌株CIY4,该链格孢属真菌具有普遍抑制常见植物病原菌的作用。

冬油菜根际土壤真菌驱动及其影响土壤肥力的生态效益分析

冬油菜是我国北方重要的油料作物和冬季覆盖作物,为探讨白菜型和甘蓝型冬油菜根际土壤真菌群落组成,及真菌驱动并影响土壤肥力的生态效益。对白菜型和甘蓝型冬油菜根际和非根际土壤微生物群落结构、土壤酶活性、土壤性质进行分析和比较。结果表明:(1)白菜型和甘蓝型冬油菜根际微生物量碳(MBC)、微生物量氮(MBN)、微生物量磷(MBP)分别较非根际增加22.8%、19.5%、27.4%、31.8%、11.4%、9.8%。(2)冬油菜土壤根际真菌α多样性显著降低,且一些致病菌如担子菌门、被孢菌门、壶菌门丰度也明显降低。(3)不同类型冬油菜根际土壤微生物群落结构存在显著差异,白菜型冬油菜的优势真菌门是子囊菌门,占比超过总丰度的83%,其次是担子菌门、被孢菌门、壶菌门、毛霉门;甘蓝型冬油菜的优势菌门是油壶菌门和Fungi_phy_Incertae_sedis。(4)冗余分析(RDA)显示,pH、有效磷(AP)、全磷(TP)、碱解氮(AN)、全氮(TN)、有机碳(SOC)和土壤含水量(SWC)是影响土壤真菌群落组成的重要环境因子。(5)真菌群落组成差异显著影响土壤酶活性,白菜型中,磷酸酶和蔗糖酶活性高于甘蓝型,过氧化氢酶则相反。(6)微生物量和土壤酶显著影响土壤理化性质,如增加AN、AP、TP含量、降低土壤盐碱度(pH降低)等,且白菜型比甘蓝型更显著。综上,种植冬油菜可通过改变根际土壤真菌群落组成及结构,进而驱动提高土壤酶活性和土壤可利用的氮、磷的含量,提高土壤肥力,调节pH,改良土壤特性,具有良好的生态效益。研究结果为冬油菜⁃土壤⁃微生物互作研究及筛选分离益生真菌提供理论参考,为进一步扩大冬季覆盖作物的种植面积,优化农业产业结构提供一定的支撑。