Infectious keratitis in Vietnam:etiology,organisms,and management at Vietnam National Eye Hospital

AIM:To report the etiologies,risk factors,treatments,and outcomes of infectious keratitis(IK)at a major Vietnamese eye hospital.METHODS:This is a retrospective review of all cases of IK at Vietnam National Eye Hospital(VNEH)in Hanoi,Vietnam.Medical histories,demographics,clinical features,microbiological results,and treatment outcomes were reviewed.RESULTS:IK was diagnosed in 1974 eyes of 1952 patients,with ocular trauma being the greatest risk factor for IK(34.2%),frequently resulting from an agriculturerelated injur y(53.3%).The mean duration between symptom onset and presentation to VNEH was 19.3±14.4 d,and 98.7%of patients had been treated with topical antibiotic and/or antifungal agents prior to evaluation at VNEH.Based on smear results of 1706 samples,the most common organisms identified were bacteria(n=1107,64.9%)and fungi(n=1092,64.0%),with identification of both bacteria and fungi in 614(36.0%)eyes.Fifty-five of 374 bacterial cultures(14.7%)and 426 of 838 fungal cultures(50.8%)were positive,with the most commonly cultured pathogens being Pseudomonas aeruginosa,Streptococcus pneumonia,Fusarium spp.,and Aspergillus spp.Corneal perforation and descemetocele developed in 391(19.8%)and 93(4.7%)eyes,respectively.Medical treatment was successful in resolving IK in 50.4%eyes,while 337(17.1%)eyes underwent penetrating or anterior lamellar keratoplasty.Evisceration was performed in 7.1%of eyes,most commonly in the setting of fungal keratitis.CONCLUSION:Ocular trauma is a major risk factor for IK in Vietnam,which is diagnosed in almost 400 patients each year at VNEH.Given this,and as approximately one quarter of the eyes that develop IK require corneal transplantation or evisceration,greater emphasis should be placed on the development of prevention and treatment programs for IK in Vietnam.

Herpes simplex keratitis:A brief clinical overview

The aim of our minireview is to provide a brief overview of the diagnosis,clinical aspects,treatment options,management,and current literature available regarding herpes simplex keratitis(HSK).This type of corneal viral infection is caused by the herpes simplex virus(HSV),which can affect several tissues,including the cornea.One significant aspect of HSK is its potential to cause recurrent episodes of inflammation and damage to the cornea.After the initial infection,the HSV can establish a latent infection in the trigeminal ganglion,a nerve cluster near the eye.The virus may remain dormant for extended periods.Periodic reactivation of the virus can occur,leading to recurrent episodes of HSK.Factors triggering reactivation include stress,illness,immunosuppression,or trauma.Recurrent episodes can manifest in different clinical patterns,ranging from mild epithelial involvement to more severe stromal or endothelial disease.The severity and frequency of recurrences vary among individuals.Severe cases of HSK,especially those involving the stroma and leading to scarring,can result in vision impairment or even blindness in extreme cases.The cornea's clarity is crucial for good vision,and scarring can compromise this,potentially leading to visual impairment.The management of HSK involves not only treating acute episodes but also implementing long-term strategies to prevent recurrences and attempt repairs of corneal nerve endings via neurotization.Antiviral medications,such as oral Acyclovir or topical Ganciclovir,may be prescribed for prophylaxis.The immune response to the virus can contribute to corneal damage.Inflammation,caused by the body's attempt to control the infection,may inadvertently harm the corneal tissues.Clinicians should be informed about triggers and advised on measures to minimize the risk of reactivation.In summary,the recurrent nature of HSK underscores the importance of both acute and long-term management strategies to preserve corneal health and maintain optimal visual function.

A surgical alternative of fusiform penetrating keratoplasty for the management of severe infectious keratitis

AIM:To describe the surgical procedure of fusiform penetrating keratoplasty(FPK)using multiple trephines of different sizes for treating patients with severe infectious keratitis.METHODS:Fourteen eyes underwent FPK,and 15 eyes received conventional penetrating keratoplasty(PK)were included in the study.The best-corrected visual acuity(BCVA),refractive outcomes,endothelial cell density,and postoperative complications were recorded.RESULTS:The FPK group was followed for an average of 15.3±2.1mo,whereas the PK group was followed for 16.1±1.9mo.The corneal ulcers were elliptical-shaped in all 14 eyes in the FPK group.The mean BCVA(logMAR,0.26±0.13)showed no statistically significant differences from that in the PK group(logMAR,0.21±0.12,P>0.05)at 1y after surgery.But the mean curvature,mean astigmatism,and mean spherical equivalent in the FPK group were lower than those in the PK group(P<0.05).Peripheral anterior synechia was observed in one patient in the FPK group,whereas 6 patients in the PK group.Suture loosening and neovascularization were observed in 4 and 5 eyes in the PK group,respectively.No graft immune rejection or elevation of intraocular pressure was observed in the two groups.CONCLUSION:For patients with elliptical-shaped corneas or corneal ulcers,FPK can avoid disrupting of corneal limbus,reduce the risk of postoperative complications,and can result in satisfactory visual quality.

Hydrogel dressings on neurotrophic keratitis in an experimental animal model

AIM:To investigate the therapeutic effects of hydrogel dressings on neurotrophic keratitis in rats.METHODS:Male Wistar rats,aged 42–56d,were randomly divided into control,experimental,and treatment groups,each consisting of five rats.The experimental and treatment groups underwent neurotrophic keratitis modeling in both eyes.After successful modeling,biomedical hydrogels formed with polyvinyl alcohol and polyvinyl pyrrolidone were used in treatment group for 7d.Ocular irritation response and keratitis index scores,Schirmer’s test,tear film break-up time(BUT),sodium fluorescein staining,and hematoxylin and eosin(HE)staining were used to evaluate the effectiveness of the treatment.RESULTS:The neurotrophic keratitis model was successfully established in rats with severe ophthalmic nerve injury,characterized by keratitis,ocular irritation,reduced tear secretion measured by decreased BUT and Schirmer test values,corneal epithelial loss,and disorganized collagen fibers in the stromal layer.Following treatment with hydrogel dressings,significant improvements were observed in keratitis scores and ocular irritation symptoms in model eyes.Although the recovery of tear secretion,as measured by the Schirmer’s test,did not show statistical differences,BUT was significantly prolonged.Fluorescein staining confirmed a reduction in the extent of corneal epithelial loss after treatment.HE staining revealed the restoration of the structural disorder in both the epithelial and stromal layers to a certain extent.CONCLUSION:Hydrogel dressing reduces ocular surface irritation,improves tear film stability,and promotes the repair and restoration of damaged epithelial cells by maintaining a moist and clean environment on the ocular surface in the rat model.

PACK-CXL vs.antimicrobial therapy for bacterial,fungal,and mixed infectious keratitis:a prospective randomized phase 3 trial

Background:Infectious keratitis is a major cause of global blindness.We tested whether standalone photoactivated chromophore corneal cross-linking(PACK-CXL)may be an efective frst-line treatment in early to moderate infectious keratitis,compared with standard antimicrobial treatment.Methods:This is a randomized,controlled,multinational phase 3 clinical trial.Participants in fve centers in Egypt,India,Iran,Israel,and China,aged≥18 years,with infectious keratitis of presumed bacterial,fungal,or mixed origin,were randomly assigned(1:1)to PACK-CXL,or antimicrobial therapy.Outcomes measures included healing,defned as time to re-epithelialization of the corneal epithelial defect in the absence of infammatory activity in the anterior chamber and clearance of stromal infltrates.Treatment success was defned as the complete resolution of signs of infection.Results:Between July 21,2016,and March 4,2020,participants were randomly assigned to receive PACK-CXL(n=18)or antimicrobial therapy per American Academy of Ophthalmology(AAO)guidelines(n=21).No participants were lost to follow-up.Four eyes were excluded from the epithelialization time analysis due to treatment failure:two in the antimicrobial therapy group,and two in the PACK-CXL group.Success rates were 88.9%(16/18 patients)in the PACK-CXL group and 90.5%(19/21 patients)in the medication group.There was no signifcant diference in time to complete corneal re-epithelialization(P=0.828)between both treatment groups.Conclusions:PACK-CXL may be an alternative to antimicrobial drugs for frst-line and standalone treatment of early to moderate infectious keratitis of bacterial or fungal origin.

CD3ε of a pan T cell marker involved in mouse Aspergillus fumigatus keratitis

AIM:To explore whether CD3ε is involved in the adaptive immunity of Aspergillus fumigatus(A.fumigatus)keratitis in mice and the role of innate and adaptive immunity in it.METHODS:Mice models of A.fumigatus keratitis were established by intra-stromal injection and corneal epithelial scratching.Subconjunctival injections of natamycin,wedelolactone,LOX-1 inhibitor(poly I)or Dectin-1 inhibitor(laminarin)were used to treat mice with A.fumigatus keratitis.Mice were pretreated by intraperitoneal injection of anti-mouse CD3ε.We observed the corneal infection of mice under the slit lamp microscope and made a clinical score.The protein expression of CD3ε and interleukin-10(IL-10)was determined by Western blotting.RESULTS:With the disease progresses,the degree of corneal opacity and edema augmented.In the intrastromal injection models,CD3εprotein expression began to increase significantly on the 2^(nd) day.However,in the scraping epithelial method models,CD3ε only began to increase on the 3^(rd) day.After natamycin treatment,the degree of corneal inflammation in mice was significantly attenuated on the 3^(rd) day.After wedelolactone treatment,the severity of keratitis worsened.And the amount of CD3ε protein was also reduced,compared with the control group.By inhibiting LOX-1 and Dectin-1,there was no significant difference in CD3ε production compared with the control group.After inhibiting CD3ε,corneal ulcer area and clinical score increased,and IL-10 expression was downregulated.CONCLUSION:As a pan T cell marker,CD3ε participate in the adaptive immunity of A.fumigatus keratitis in mice.In our mice models,the corneas will enter the adaptive immune stage faster.By regulating IL-10,CD3ε exerts antiinflammatory and repairs effects in the adaptive immune stage.

Bilateral meibomian gland morphological alterations in unilateral herpes simplex keratitis based on artificial intelligence analysis

AIM:To explore whether unilateral herpes simplex keratitis(HSK)can cause morphological changes of bilateral meibomian glands(MGs)based on artificial intelligence(AI)analytical system.METHODS:In the retrospective study,29 patients with unilateral HSK and 29 participants matched in terms of age and sex were included as control group.Meibographic images of the upper eyelid using Keratograph 5M and assessed ocular surface parameters including tear meniscus height and tear break-up time.MG density and vagueness values were automatically analyzed and calculated using an AI analytical system.We compared the differences between the affected and the contralateral unaffected eyes in HSK patients,and the normal control eyes.We employed either the paired t-test or the Wilcoxon signed-rank test to compare significant difference between the affected and unaffected eyes in HSK patients or between the HSK group and control group.RESULTS:The MG density was 0.19±0.09 in the HSKaffected eye and 0.18±0.07 in contralateral unaffected eye,which had no significant difference(P=0.616).The MG density between the affected eye with HSK and the normal control group was statistically significant(P=0.028).There was a significant difference in MG density between the contralateral unaffected eye and the normal control group(P=0.012).However,no significant difference in vagueness value was observed between the eye with HSK and the control group or between HSK eye and contralateral eye.CONCLUSION:The MG density between the HSKaffected eye and the contralateral unaffected eye don’t significantly differ,whereas there is a significant decrease in the HSK group compared to that of the normal participants.Unilateral HSV keratitis may suffer from bilateral changes of MG morphology indicating bilateral dry eye.Therefore,the fellow eye of patients with unilateral HSK should be considered a potential case of MG dysfunction,necessitating early treatment for bilateral dry eye in the clinic.

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. .

Sensitivity of diagnosis of spontaneous bacterial peritonitis is higher with the automated cell count method

BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection is key in the outcome of these patients.The current definition of SBP is based on studies performed more than 40 years ago using a manual technique to count the number of polymorphs in ascitic fluid(AF).There is a lack of data comparing the traditional cell count method with a current automated cell counter.Moreover,current international guidelines do not mention the type of cell count method to be employed and around half of the centers still rely on the traditional manual method.AIM To compare the accuracy of polymorph count on AF to diagnose SBP between the traditional manual cell count method and a modern automated cell counter against SBP cases fulfilling gold standard criteria:Positive AF culture and signs/symptoms of peritonitis.METHODS Retrospective analysis including two cohorts:Cross-sectional(cohort 1)and case-control(cohort 2),of patients with decompensated cirrhosis and ascites.Both cell count methods were conducted simultaneously.Positive SBP cases had a pathogenic bacteria isolated on AF and signs/symptoms of peritonitis.RESULTS A total of 137 cases with 5 positive-SBP,and 85 cases with 33 positive-SBP were included in cohort 1 and 2,respectively.Positive-SBP cases had worse liver function in both cohorts.The automated method showed higher sensitivity than the manual cell count:80%vs 52%,P=0.02,in cohort 2.Both methods showed very good specificity(>95%).The best cutoff using the automated cell counter was polymorph≥0.2 cells×10^(9)/L(equivalent to 200 cells/mm^(3))in AF as it has the higher sensitivity keeping a good specificity.CONCLUSION The automated cell count method should be preferred over the manual method to diagnose SBP because of its higher sensitivity.SBP definition,using the automated method,as polymorph cell count≥0.2 cells×10^(9)/L in AF would need to be considered in patients admitted with decompensated cirrhosis.

Improving treatment plan and mental health in children with abdominal infection for broad-spectrum bacterial infections

BACKGROUND Pediatric abdominal infection is a common but serious disease that requires timely and effective treatment.In surgical treatment,accurate diagnosis and rational application of antibiotics are the keys to improving treatment effects.AIM To investigate the effect of broad-spectrum bacterial detection on postoperative antibiotic therapy.METHODS A total of 100 children with abdominal infection who received surgical treatment in our hospital from September 2020 to July 2021 were grouped.The observation group collected blood samples upon admission and sent them for broad-spectrum bacterial infection nucleic acid testing,and collected pus or exudate during the operation for bacterial culture and drug sensitivity testing;the control group only sent bacterial culture and drug sensitivity testing during the operation.RESULTS White blood cell count,C-reactive protein,procalcitonin,3 days after surgery,showed better postoperative index than the control group(P<0.05).The hospital stay in the observation group was significantly shorter than that in the control group.The hospitalization cost in the observation group was significantly lower than that in the control group,and the difference between the two groups was statistically significant(P<0.05).CONCLUSION Early detection of broad-spectrum bacterial infection nucleic acids in pediatric abdominal infections can help identify pathogens sooner and guide the appropriate use of antibiotics,improving treatment outcomes and reducing medical costs to some extent.

Immune response to inactivated bacterial vector carrying the recombinant K39 antigen of Leishmania infantum in mice

Objective:To evaluate the immunological response elicited by an inactivated bacterial vector carrying the K39 antigen of Leishmania infantum,and a purified antigen.Methods:Mice were subjected to the following treatments:(1)Purified recombinant K39(rK39)protein at a 20μg dose with complete Freund’s adjuvant;(2)Inactivated Escherichia coli(BL21 DE3)carrying the K39 protein at an equivalent total protein content of 200μg;(3)Inactivated bacteria lacking the K39 protein;(4)Non-immunized control animals.Serological monitoring was performed.All groups were challenged by intraperitoneal injection of 10^(7) Leishmania infantum promastigotes.After euthanasia,the liver and spleen were collected to analyze the levels of TNF,IFN-γ,IL-12,IL-4,and IL-10.Results:Mice immunized with purified rK39 or the inactivated bacterial vector carrying the K39 antigen of Leishmania infantum showed a long-lasting immune response with high levels of polyclonal antibodies specifically recognizing the recombinant proteins.The IgG1 subclass was the predominant immunoglobulin;however,the induction of IgG2a and the profile of cytokines produced were indicative of the induction of a mixed-type response.Conclusions:The inactivated bacterial vector carrying the K39 antigen,as well as the purified antigen can induce a long-lasting immune response in immunized mice,predominantly favouring a Th2 profile response.

A comparative study for petroleum removal capacities of the bacterial consortia entrapped in sodium alginate,sodium alginate/poly(vinyl alcohol),and bushnell haas agar

The purpose of this study was to identify and compare the degradation efficiencies of free and entrapped bacterial consortia(Staphylococcus capitis CP053957.1 and Achromobacter marplatensis MT078618.1)to different polymers such as Sodium Alginate(SA),Sodium Alginate/Poly(Vinyl Alcohol)(SA/PVA),and Bushnell Haas Agar(BHA).In addition to SA and SA/PVA,which are cost-effective,non-toxic and have different functional groups,BHA,which is frequently encountered in laboratory-scale studies but has not been used as an entrapment material until now.Based on these,the polymers with different surface morphologies and chemical compositions were analyzed by SEM and FT-IR.While the petroleum removal efficiency was higher with the entrapped bacterial consortia than with the free one,BHA-entrapped bacterial consortium enhanced the petroleum removal more than SA and SA/PVA.Accordingly,the degradation rate of bacterial consortia entrapped with BHA was 2.039 day^(-1),SA/PVA was 1.560,SA was 0.993,the half-life period of BHA-entrapped bacterial consortia is quite low(t_(1/2)=0.339)compared with SA(t_(1/2)=0.444)and SA/PVA(t_(1/2)=0.697).The effects of the four main factors such as:amount of BHA(0.5,1,1.5,2,2.5,3 g),disc size(4,5,6,7,8 mm),inoculum concentration(1,2.5,5,7.5,10 mL),and incubation period on petroleum removal were also investigated.The maximum petroleum removal(94.5%)was obtained at≥2.5 mL of bacterial consortium entrapped in 2 g BHA with a 7 mm disc size at 168 h and the results were also confirmed by statistical analysis.Although a decrease was observed during the reuse of bacterial consortium entrapped in BHA,the petroleum removal was still above 50%at 10th cycle.Based on GC-MS analysis,the removal capacity of BHA-entrapped consortium was over 90%for short-chain n-alkanes and 80%for medium-chain n-alkanes.Overall,the obtained data are expected to provide a potential guideline in cleaning up the large-scale oil pollution in the future.Since there has been no similar study investigating petroleum removal with the bacterial consortia entrapped with BHA,this novel entrapment material can potentially be used in the treatment of petroleum pollution in advanced remediation studies.

Development of Spectral Features for Monitoring Rice Bacterial Leaf Blight Disease Using Broad-Band Remote Sensing Systems

As an important rice disease, rice bacterial leaf blight (RBLB, caused by the bacterium Xanthomonas oryzae pv.oryzae), has become widespread in east China in recent years. Significant losses in rice yield occurred as a result ofthe disease’s epidemic, making it imperative to monitor RBLB at a large scale. With the development of remotesensing technology, the broad-band sensors equipped with red-edge channels over multiple spatial resolutionsoffer numerous available data for large-scale monitoring of rice diseases. However, RBLB is characterized by rapiddispersal under suitable conditions, making it difficult to track the disease at a regional scale with a single sensorin practice. Therefore, it is necessary to identify or construct features that are effective across different sensors formonitoring RBLB. To achieve this goal, the spectral response of RBLB was first analyzed based on the canopyhyperspectral data. Using the relative spectral response (RSR) functions of four representative satellite or UAVsensors (i.e., Sentinel-2, GF-6, Planet, and Rededge-M) and the hyperspectral data, the corresponding broad-bandspectral data was simulated. According to a thorough band combination and sensitivity analysis, two novel spectralindices for monitoring RBLB that can be effective across multiple sensors (i.e., RBBRI and RBBDI) weredeveloped. An optimal feature set that includes the two novel indices and a classical vegetation index was formed.The capability of such a feature set in monitoring RBLB was assessed via FLDA and SVM algorithms. The resultdemonstrated that both constructed novel indices exhibited high sensitivity to the disease across multiple sensors.Meanwhile, the feature set yielded an overall accuracy above 90% for all sensors, which indicates its cross-sensorgenerality in monitoring RBLB. The outcome of this research permits disease monitoring with different remotesensing data over a large scale.

High-throughput screening system of citrus bacterial cankerassociated transcription factors and its application to the regulation of citrus canker resistance

One of the main diseases that adversely impacts the global citrus industry is citrus bacterial canker(CBC),caused by the bacteria Xanthomonas citri subsp.citri(Xcc).Response to CBC is a complex process,with both proteinDNA as well as protein–protein interactions for the regulatory network.To detect such interactions in CBC resistant regulation,a citrus high-throughput screening system with 203 CBC-inducible transcription factors(TFs),were developed.Screening the upstream regulators of target by yeast-one hybrid(Y1H)methods was also performed.A regulatory module of CBC resistance was identified based on this system.One TF(CsDOF5.8)was explored due to its interactions with the 1-kb promoter fragment of CsPrx25,a resistant gene of CBC involved in reactive oxygen species(ROS)homeostasis regulation.Electrophoretic mobility shift assay(EMSA),dual-LUC assays,as well as transient overexpression of CsDOF5.8,further validated the interactions and transcriptional regulation.The CsDOF5.8–CsPrx25 promoter interaction revealed a complex pathway that governs the regulation of CBC resistance via H2O2homeostasis.The high-throughput Y1H/Y2H screening system could be an efficient tool for studying regulatory pathways or network of CBC resistance regulation.In addition,it could highlight the potential of these candidate genes as targets for efforts to breed CBC-resistant citrus varieties.

Systematic analysis and functional verification of citrus glutathione S-transferases reveals that CsGSTF1 and CsGSTU18contribute negatively to citrus bacterial canker

Citrus bacterial canker(CBC) is resulted from Xanthomonas citri subsp. citri(Xcc) infection and poses a significant threat to citrus production.Glutathione S-transferases(GSTs) are critical in maintaining redox homeostasis in plants, especially in relation to abiotic and biotic stress responses. However, the function of GSTs in resisting CBC remains unclear. Here, citrus glutathione S-transferases were investigated applying a genome-wide approach. In total, 69 CsGSTs belonging to seven classes were identified, and the phylogeny, chromosomal distribution, gene structures and conserved motifs were analyzed. Several CsGSTs responded to Xcc infection, as observed in the upregulation of CsGSTF1 and CsGSTU18 in the CBC-sensitive ‘Wanjincheng' variety but not in the resistant ‘Kumquat' variety. CsGSTF1 and CsGSTU18 were localized at the cytoplasm. Transient overexpression of CsGSTF1 and CsGSTU18 mediated reactive oxygen species(ROS) scavenging, whereas the virus-induced gene silencing(VIGS) of CsGSTF1 and CsGSTU18 caused strong CBC resistance and ROS burst. The present study investigated the characterization of citrus GST gene family, and discovered that CsGSTF1 and CsGSTU18 negatively contributed to CBC through modulating ROS homeostasis. These findings emphasize the significance of GSTs in infection resistance in plants.

Evaluating the accuracy and reproducibility of ChatGPT-4 in answering patient questions related to small intestinal bacterial overgrowth

BACKGROUND Small intestinal bacterial overgrowth(SIBO)poses diagnostic and treatment challenges due to its complex management and evolving guidelines.Patients often seek online information related to their health,prompting interest in large language models,like GPT-4,as potential sources of patient education.AIM To investigate ChatGPT-4's accuracy and reproducibility in responding to patient questions related to SIBO.METHODS A total of 27 patient questions related to SIBO were curated from professional societies,Facebook groups,and Reddit threads.Each question was entered into GPT-4 twice on separate days to examine reproducibility of accuracy on separate occasions.GPT-4 generated responses were independently evaluated for accuracy and reproducibility by two motility fellowship-trained gastroenterologists.A third senior fellowship-trained gastroenterologist resolved disagreements.Accuracy of responses were graded using the scale:(1)Comprehensive;(2)Correct but inadequate;(3)Some correct and some incorrect;or(4)Completely incorrect.Two responses were generated for every question to evaluate reproducibility in accuracy.RESULTS In evaluating GPT-4's effectiveness at answering SIBO-related questions,it provided responses with correct information to 18/27(66.7%)of questions,with 16/27(59.3%)of responses graded as comprehensive and 2/27(7.4%)responses graded as correct but inadequate.The model provided responses with incorrect information to 9/27(33.3%)of questions,with 4/27(14.8%)of responses graded as completely incorrect and 5/27(18.5%)of responses graded as mixed correct and incorrect data.Accuracy varied by question category,with questions related to“basic knowledge”achieving the highest proportion of comprehensive responses(90%)and no incorrect responses.On the other hand,the“treatment”related questions yielded the lowest proportion of comprehensive responses(33.3%)and highest percent of completely incorrect responses(33.3%).A total of 77.8%of questions yielded reproducible responses.CONCLUSION Though GPT-4 shows promise as a supplementary tool for SIBO-related patient education,the model requires further refinement and validation in subsequent iterations prior to its integration into patient care.

Effects of water tables and nitrogen application on soil bacterial community diversity, network structure, and function in an alpine wetland, China

Nitrogen deposition and water tables are important factors to control soil microbial community structure.However,the specific effects and mechanisms of nitrogen deposition and water tables coupling on bacterial diversity,abundance,and community structure in arid alpine wetlands remain unclear.The nitrogen deposition(0,10,and 20 kg N/(hm^(2)•a))experiments were conducted in the Bayinbulak alpine wetland with different water tables(perennial flooding,seasonal waterlogging,and perennial drying).The 16S rRNA(ribosomal ribonucleic acid)gene sequencing technology was employed to analyze the changes in bacterial community diversity,network structure,and function in the soil.Results indicated that bacterial diversity was the highest under seasonal waterlogging condition.However,nitrogen deposition only affected the bacterial Chao1 and beta diversity indices under seasonal waterlogging condition.The abundance of bacterial communities under different water tables showed significant differences at the phylum and genus levels.The dominant phylum,Proteobacteria,was sensitive to soil moisture and its abundance decreased with decreasing water tables.Although nitrogen deposition led to changes in bacterial abundance,such changes were small compared with the effects of water tables.Nitrogen deposition with 10 kg N/(hm^(2)•a)decreased bacterial edge number,average path length,and robustness.However,perennial flooding and drying conditions could simply resist environmental changes caused by 20 kg N/(hm^(2)•a)nitrogen deposition and their network structure remain unchanged.The sulfur cycle function was dominant under perennial flooding condition,and carbon and nitrogen cycle functions were dominant under seasonal waterlogging and perennial drying conditions.Nitrogen application increased the potential function of part of nitrogen cycle and decreased the potential function of sulfur cycle in bacterial community.In summary,composition of bacterial community in the arid alpine wetland was determined by water tables,and diversity of bacterial community was inhibited by a lower water table.Effect of nitrogen deposition on bacterial community structure and function depended on water tables.

Investigation of Kiwifruit Bacterial Canker Disease(Pseudomonas syringae pv.Actinidiae Takikawa) in Guanzhong Area of Shanxi Province and Its Biological Control

[ Objective ] The paper was to grasp the incidence characteristic of kiwifruit bacterial canker disease （Pseudomonas syrirtgate pv. actinidiae Takikawa） in Guanzhong area of Shanxi province, and to screen the endophytic actinomycetes with control effect against kiwifruit bacterial canker. [ Method] The incidence characteristics of kiwifruit bacterial canker disease in 65 orchards of 13 villages in guanzhong area of Shanxi province （Yangling, Zhouzhi, Meixian） were investiga- ted and analyzed. The antagonistic strains against Pseudomonas syringae were simultaneously screened from 242 endophytic actinomycetes, and carried out field dis- ease control test. [ Result] The average incidence rate of kiwifruit bacterial canker disease in guan^ong area of Shanxi province was 7.95% ; the variety of kiwifruit had dose relationship with incidence rate. 76 strains bad inhibition activity agmnst P. syringae, while the inhibition zone diameters of fermentation broths of 35 strains against P. syr/ngae were greater than 20 nun. TIASA5 strain had inhibition activity against four target bacteria; gCLA4 strain not only had inhibition activity against four target bacteria, but also had strong inhibition activity against 10 species of plant pathogenic fungi. Field test showed that the fermentation broth of gCLA4 strain had obvious control effect against kiwifruit bacterial canker disease, and the relative control effect at 21 d could reach 66.7%. [ Conclusion] The an- tibacterial spectrum of fermentation broth of gCLA4 strain is broad, so gCLA4 strain has the potential to be developed into a broad-spectrum agricultural fungicide. Key words Kiwifruit bacterial canker disease; Endophytic actinomycetes; Biological control; Field test

Response of Bacterial Community and Enzyme Activity of Greenhouse Tomato under Different Irrigation Systems

The micro-sprinkler irrigation mulched(MSM)has been suggested as a novel water-saving approach in con-trolled environment agriculture.However,the effects of microbial community structure and enzyme activity in the rhizosphere soil on crop growth under MSM remain unclear.This study conducted a randomized experimen-tal design using greenhouse tomatoes to investigate changes in bacterial community structure and enzyme activity in rhizosphere soil under different irrigation frequencies(F)and amounts(I)of MSM.Thefindings revealed that with the increase of F or I,The total count of soil bacteria in tomatoesfirst rose and then fell in terms of Opera-tional Taxonomic Units(OTUs)classification.Compared to other F,the most abundance of nitrogen and phos-phorus metabolism genes and enzyme activities were observed with a 5-day F.Moreover,the diversity of soil bacterial community structure initially rose before eventually declining with the increase of the I.Applying 1.00 Epan(cumulative evaporation of a 20 cm standard pan)under MSM helped boost the abundance of nitrogen and phosphorus metabolism functional genes in soil bacteria,ensuring higher enzyme activities related to nitro-gen,carbon,and phosphorus metabolism in the rhizosphere soil of tomatoes.Tomatoes’yield initially rose before eventually declining with the increase in F or I,whereas I had a more significant effect on yield.A 1.00%increase in I yielded a minimum of 39.24%increase in tomato yield.The study showed a positive correlation between soil bacterial community,soil enzyme activity,and greenhouse tomato yield under MSM.Considering the results comprehensively,the combined irrigation mode of F of 5 d and I of 1.00 Epan was recommended for greenhouse tomatoes under MSM.This conclusion provides theoretical support for water-saving practices and yield improve-ment in facility agriculture,especially tomato cultivation.

Oxygen vacancy boosting Fenton reaction in bone scaffold towards fighting bacterial infection

Bacterial infection is a major issue after artificial bone transplantation due to the absence of antibacterial function of bone scaffold,which seriously causes the transplant failure and even amputation in severe cases.In this study,oxygen vacancy(OV)defects Fe-doped Ti O2(OV-FeTiO2)nanoparticles were synthesized by nano TiO2and Fe3O4via high-energy ball milling,which was then incorporated into polycaprolactone/polyglycolic acid(PCLGA)biodegradable polymer matrix to construct composite bone scaffold with good antibacterial activities by selective laser sintering.The results indicated that OV defects were introduced into the core/shell-structured OV-FeTiO2nanoparticles through multiple welding and breaking during the high-energy ball milling,which facilitated the adsorption of hydrogen peroxide(H2O2)in the bacterial infection microenvironment at the bone transplant site.The accumulated H2O2could amplify the Fenton reaction efficiency to induce more hydroxyl radicals(·OH),thereby resulting in more bacterial deaths through·OH-mediated oxidative damage.This antibacterial strategy had more effective broad-spectrum antibacterial properties against Gram-negative Escherichia coli(E.coli)and Gram-positive Staphylococcus aureus(S.aureus).In addition,the PCLGA/OV-FeTiO2scaffold possessed mechanical properties that match those of human cancellous bone and good biocompatibility including cell attachment,proliferation and osteogenic differentiation.