Bronchoalveolar lavage fluid metagenomic next-generation sequencing assay for identifying pathogens in lung cancer patients

Background:For patients with lung cancer,timely identification of new lung lesions as infectious or non-infectious,and accurate identification of pathogens is very important in improving OS of patients.As a new auxiliary examination,metagenomic next-generation sequencing(mNGS)is believed to be more accurate in diagnosing infectious diseases in patients without underlying diseases,compared with conventional microbial tests(CMTs).We designed this study tofind out whether mNGS has better performance in distinguishing infectious and non-infectious diseases in lung cancer patients using bronchoalveolar lavagefluid(BALF).Materials and Methods:This study was a real-world retrospective review based on electronic medical records of lung cancer patients with bronchoalveolar lavage(BAL)and BALF commercial mNGS testing as part of clinical care from 1 April 2019 through 30 April 2022 at The First Affiliated Hospital of Sun Yat-sen University.164 patients were included in this study.Patients were categorized into the pulmonary non-infectious disease(PNID)group(n=64)and the pulmonary infectious disease(PID)group(n=100)groups based onfinal diagnoses.Results:BALF mNGS increased the sensitivity rate by 60%compared to CMTs(81%vs.21%,p<0.05),whereas there was no significant difference in specificity(75%vs.98.4%,p>0.1).Among the patients with PID,bacteria were the most common cause of infection.Fungal infections occurred in 32%of patients,and Pneumocystis Yersini was most common.Patients with Tyrosine kinase inhibitors(TKIs)therapy possess longer overall survival(OS)than other anti-cancer agents,the difference between TKIs and immuno-checkpoint inhibitors(ICIs)was insignificant(median OS TKIs vs.ICIs vs.Anti-angiogenic vs.Chemo vs.Radiotherapy=76 vs.84 vs.61 vs.58 vs.60).Conclusions:our study indicates that BALF mNGS can add value by improving overall sensitivity in lung cancer patients with potential pulmonary infection,and was outstanding in identifying Pneumocystis infection.It could be able to help physicians adjust the follow-up treatment to avoid the abuse of antibiotics.

Brain abscess from oral microbiota approached by metagenomic next-generation sequencing: A case report and review of literature

BACKGROUND Brain abscess is a serious and potentially fatal disease caused primarily by microbial infection.Although progress has been made in the diagnosis and treatment of brain abscesses,the diagnostic timeliness of pathogens needs to be improved.CASE SUMMARY We report the case of a 54-year-old male with a brain abscess caused by oral bacteria.The patient recovered well after receiving a combination of metagenomic next-generation sequencing(mNGS)-assisted guided medication and surgery.CONCLUSION Therefore,mNGS may be widely applied to identify the pathogenic microor-ganisms of brain abscesses and guide precision medicine.

Metagenomic next-generation sequencing may assist diagnosis of osteomyelitis caused by Mycobacterium houstonense:A case report

BACKGROUND Mycobacterium houstonense(M.houstonense)belongs to the nontuberculous mycobacterium group.Infection caused by M.houstonense is prone to recurrence.CASE SUMMARY We present a patient who was diagnosed with osteomyelitis caused by M.houstonense and treated with a combination of cefoxitin,and amikacin combined with linezolid.CONCLUSION The emergence of metagenomic next-generation sequencing(NGS)has brought new hope for the diagnosis and treatment of listeria meningitis.NGS can analyze a large number of nucleic acid sequences in a short time and quickly determine the pathogen species in the sample.Compared with traditional cerebrospinal fluid culture,NGS can greatly shorten the diagnosis time and provide strong support for the timely treatment of patients.Regarding treatment,NGS can also play an important role.Rapid and accurate diagnosis can enable patients to start targeted treatment as soon as possible and improve the treatment effect.At the same time,by monitoring the changes in pathogen resistance,the treatment plan can be adjusted in time to avoid treatment failure.

Diagnosis of Acute Q Fever in an Elderly Patient Using Metagenomic Next-Generation Sequencing:A Case Report

Query fever(Q fever)is a globally spread zoonotic disease caused by Coxiella burnetii,commonly found in natural foci but rarely seen in Hebei Province.The clinical manifestations of Q fever are diverse and nonspecific,which often leads to missed or incorrect diagnoses in clinical practice.This article reports a case of acute Q fever diagnosed in an elderly patient using metagenomic next-generation sequencing.

Pulmonary nocardiosis with bloodstream infection diagnosed by metagenomic next-generation sequencing in a kidney transplant recipient:A case report

BACKGROUND Pulmonary nocardiosis is difficult to diagnose by culture and other conventional testing,and is often associated with lethal disseminated infections.This difficulty poses a great challenge to the timeliness and accuracy of clinical detection,especially in susceptible immunosuppressed individuals.Metagenomic nextgeneration sequencing(mNGS)has transformed the conventional diagnosis pattern by providing a rapid and precise method to assess all microorganisms in a sample.CASE SUMMARY A 45-year-old male was hospitalized for cough,chest tightness and fatigue for 3 consecutive days.He had received a kidney transplant 42 d prior to admission.No pathogens were detected at admission.Chest computed tomography showed nodules,streak shadows and fiber lesions in both lung lobes as well as right pleural effusion.Pulmonary tuberculosis with pleural effusion was highly suspected based on the symptoms,imaging and residence in a high tuberculosisburden area.However,anti-tuberculosis treatment was ineffective,showing no improvement in computed tomography imaging.Pleural effusion and blood samples were subsequently sent for mNGS.The results indicated Nocardia farcinica as the major pathogen.After switching to sulphamethoxazole combined with minocycline for antinocardiosis treatment,the patient gradually improved and was finally discharged.CONCLUSION A case of pulmonary nocardiosis with an accompanying bloodstream infection was diagnosed and promptly treated before the dissemination of the infection.This report emphasizes the value of mNGS in the diagnosis of nocardiosis.mNGS may be an effective method for facilitating early diagnosis and prompt treatment in infectious diseases,which overcomes the shortcomings of conventional testing.

Metagenomic next-generation sequencing for pleural effusions induced by viral pleurisy:A case report

BACKGROUND Viral pleurisy is a viral infected disease with exudative pleural effusions.It is one of the causes for pleural effusions.Because of the difficult etiology diagnosis,clinically pleural effusions tend to be misdiagnosed as tuberculous pleurisy or idiopathic pleural effusion.Here,we report a case of pleural effusion secondary to viral pleurisy which is driven by infection with epstein-barr virus.Viral infection was identified by metagenomic next-generation sequencing(mNGS).CASE SUMMARY A 40-year-old male with a history of dermatomyositis,rheumatoid arthritis,and secondary interstitial pneumonia was administered with long-term oral prednisone.He presented with fever and chest pain after exposure to cold,accompanied by generalized sore and weakness,night sweat,occasional cough,and few sputums.The computed tomography scan showed bilateral pleural effusions and atelectasis of the partial right lower lobe was revealed.The pleural fluids were found to be yellow and slightly turbid after pleural catheterization.Thoracoscopy showed fibrous adhesion and auto-pleurodesis.Combining the results in pleural fluid analysis and mNGS,the patient was diagnosed as viral pleuritis.After receiving Aciclovir,the symptoms and signs of the patient were relieved.CONCLUSION Viral infection should be considered in cases of idiopathic pleural effusion unexplained by routine examination.mNGS is helpful for diagnosis.

Metagenomic next-generation sequencing in the diagnosis of neurocysticercosis:A case report

BACKGROUND The clinical symptoms and imaging manifestations of neurocysticercosis(NCC)are very different,and the difficulty and delay of clinical diagnoses may lead to an increase in mortality and disability.Rapid and accurate pathogen identification is important for the treatment of these patients.Metagenomic next-generation sequencing(mNGS)is a powerful tool to identify pathogens,especially in infections that are difficult to identify by conventional methods.CASE SUMMARY A 43-year-old male patient was admitted due to a recurrent headache for a few months.Imaging examinations showed hydrocephalus and cystic lesions,which were considered to be a central nervous system infection,but no etiology was found by routine examination.mNGS of the cerebrospinal fluid revealed high Taenia solium reads,and the positive results of a cysticercosis antibody test confirmed the infection.Combined with the patient’s clinical manifestations,the etiological evidence,and the imaging manifestation,the patient was finally diagnosed with NCC and he was prescribed dexamethasone,albendazole,neurotrophic drugs,and intracranial pressure reduction therapy.The headaches disappeared after anti-parasite treatment,and no associated symptoms recurred prior to the three-and six-month follow-up.CONCLUSION As an accurate and sensitivity detection method,mNGS can be a reliable approach for the diagnosis of NCC.

Application of Next Generation Sequencing for Rapid Identification of Lactic Acid Bacteria

The rapid identification of lactic acid bacteria,which are essential microorganisms in the food industry,is of great significance for industrial applications.The identification of lactic acid bacteria traditionally relies on the isolation and identification of pure colonies.While this method is well-established and widely used,it is not without limitations.The subjective judgment inherent in the isolation and purification process introduces potential for error,and the incomplete nature of the isolation process can result in the loss of valuable information.The advent of next generation sequencing has provided a novel approach to the rapid identification of lactic acid bacteria.This technology offers several advantages,including rapidity,accuracy,high throughput,and low cost.Next generation sequencing represents a significant advancement in the field of DNA sequencing.Its ability to rapidly and accurately identify lactic acid bacteria strains in samples with insufficient information or in the presence of multiple lactic acid bacteria sets it apart as a valuable tool.The application of this technology not only circumvents the potential errors inherent in the traditional method but also provides a robust foundation for the expeditious identification of lactic acid bacteria strains and the authentication of bacterial powder in industrial applications.This paper commences with an overview of traditional and molecular biology methods for the identification of lactic acid bacteria.While each method has its own advantages,they are not without limitations in practical application.Subsequently,the paper provides an introduction of the principle,process,advantages,and disadvantages of next generation sequencing,and also details its application in strain identification and rapid identification of lactic acid bacteria.The objective of this study is to provide a comprehensive and reliable basis for the rapid identification of industrial lactic acid bacteria strains and the authenticity identification of bacterial powder.

Next Generation Sequencing in Oncological Diagnostics: Hype or Hope?

The understanding of how genetic and epigenetic factors influence tumorigenesis, progression and invasion, is vastly growing since new technologies allow the analysis of the functional genome namely the exome, the transcriptome and the epigenome, besides enabling genome-wide assessment of genetic variations. With the advent of new drugs that are indicated tissue agnostic, depending on certain mutations, there is a growing demand for fast and cost-effective genetic diagnosis. The method in focus that already became an indispensable tool in viral diagnosis is next-generation sequencing (NGS). This approach allows sequencing of literally every DNA molecule in the sample and can either be used to assess numerous genetic markers of one patient at a time, or to assess fewer markers of many patients in parallel, which reduces costs. We submitted 23 samples of different tumor entities to four diagnostic companies with different analysis profiles. The results as disclosed and discussed in this report indicate that so far, the main application of NGS is rather in cancer research than in diagnosis, as none of the reports had a real impact on the therapeutic scheme. We are perfectly aware that such a small cohort cannot be generalized, but considering the costs vs. benefits, NGS should be engaged upon a very stringent evaluation only. However, in cases where obtaining a tissue biopsy is impossible or unfavorable, analysis of liquid biopsy by NGS provides a vital alternative.

Effects of viral infection and microbial diversity on patients with sepsis:A retrospective study based on metagenomic next-generation sequencing

BACKGROUND: The study aims to investigate the performance of a metagenomic next-generationsequencing (NGS)-based diagnostic technique for the identifi cation of potential bacterial and viral infectionsand eff ects of concomitant viral infection on the survival rate of intensive care unit (ICU) sepsis patients.METHODS: A total of 74 ICU patients with sepsis who were admitted to our institution from February1, 2018 to June 30, 2019 were enrolled. Separate blood samples were collected from patients for bloodcultures and metagenomic NGS when the patients’ body temperature was higher than 38 °C. Patients’demographic data, including gender, age, ICU duration, ICU scores, and laboratory results, were recorded.The correlations between pathogen types and sepsis severity and survival rate were evaluated.RESULTS: NGS produced higher positive results (105 of 118;88.98%) than blood cultures(18 of 118;15.25%) over the whole study period. Concomitant viral infection correlated closelywith sepsis severity and had the negative effect on the survival of patients with sepsis. However,correlation analysis indicated that the bacterial variety did not correlate with the severity of sepsis.CONCLUSIONS: Concurrent viral load correlates closely with the severity of sepsis and thesurvival rate of the ICU sepsis patients. This suggests that prophylactic administration of antiviraldrugs combined with antibiotics may be benefi cial to ICU sepsis patients.

The Diagnostic Value of Metagenomic Next-Generation Sequencing in <i>Angiostrongylus cantonensis</i>Encephalitis/Meningitis

Objective: Angiostrongylus cantonensis (A. cantonensis) is an important parasite, which causes neurological infection in children, and is generally difficult to diagnose. We analyzed the significance of metagenomic next-generation sequencing in diagnosing A. cantonensis encephalitis/meningitis in children to provide a reference for clinical diagnosis. Methods: The case collection of A. cantonensis encephalitis/meningitis was from July 2018 to August 2020. The patients’ clinical characteristics and pathogen were described, and diagnostic sensitivity methods for A. cantonensis encephalitis/meningitis were compared and analyzed, including parasite antibody detection and metagenomic next-generation sequencing (mNGS) detection in different samples. Results: Eleven cases were diagnosed with A. cantonensis encephalitis/meningitis, including six males (54.5%) and five females (45.5%), and the age ranged from 1 to 13 years with a median of 21 months (IQR: 15.6, 96). All patients were undiagnosed upon admission, of which ten cases had neurological symptoms or signs, six cases (54.5%) had a history of definite or suspicious exposure to parasites, and eight cases (72.7%) had abnormal changes in cranial MRI. The results of A. cantonensis antibodies in the peripheral blood and cerebrospinal fluid (CSF) were compared with CSF’s metagenomic next-generation sequencing (mNGS). The antibody-positive rate of peripheral blood was 54.5%, CSF antibody-positive rate was 27.2%, and mNGS-positive rate of CSF was 81.8%, and the positive diagnostic rate of the latter was significantly higher than the former two (p = 0.035 < 0.05 and p = 0.030 < 0.05, respectively). Conclusion: Metagenomic next-generation sequencing has a higher positive rate for diagnosing infection and plays an important role in clarifying diagnosis and reducing misdiagnosis.

Diagnostic value of metagenomics next-generation sequencing technology in disseminated strongyloidiasis

The symptoms of disseminated strongyloidiasis are not typical,and it is difficult for clinicians to identify strongyloidiasis in some non-endemic areas.We report a 70-year-old woman who was diagnosed with Guillain-Barrésyndrome due to autonomic disturbance,symmetrical bulbar palsy,and lower-motor-nerve damage in the extremities;her symptoms continued to worsen after hormone and immunoglobulin therapy.Later,parasitic larvae were found in the patient’s gastric fluid,and metagenomic next generation sequencing(mNGS)detection of bronchoalveolar-lavage fluid also found a large number of Strongyloides roundworms.The patient was diagnosed with disseminated strongyloidiasis.The patient was given albendazole for anthelmintic treatment,but died two days after being transferred to the intensive care unit due to the excessive strongyloidiasis burden.In recent years,mNGS has been increasingly used in clinical practice,and is becoming the main means of detecting strongyloides stercoralis in non-endemic areas.Especially during the corona virus disease 2019 pandemic,mNGS technology has irreplaceable value in identifying the source of infection.

Successful treatment of disseminated nocardiosis diagnosed by metagenomic next-generation sequencing:A case report and review of literature

BACKGROUND Nocardia paucivorans is an infrequently found bacterium with the potential to cause severe infection,with a predilection for the central nervous system,both in immunocompromised and immunocompetent individuals.Rapid etiological diagnosis of nocardiosis can facilitate timely and rational antimicrobial treatment.Metagenomic next-generation sequencing(m NGS)can improve the rate and reduce the turnaround time for the detection of Nocardia.CASE SUMMARY A 49-year-old man was admitted to hospital with cough and hemoptysis.Imaging revealed pulmonary consolidation as well as multiple brain lesions.Nocardia asiatica and Nocardia beijingensis were rapidly detected by m NGS of bronchoalveolar lavage fluid(BALF)while bacterial culture of BALF and pathological biopsy of lung tissue were negative.In early stages,he was treated with trimethoprim-sulfamethoxazole(TMP-SMZ)and linezolid by individual dose adjustment based on serum concentrations and the adverse effects of thrombocytopenia and leukopenia.The treatment was then replaced by TMP-SMZ and ceftriaxone or minocycline.He was treated with 8 mo of parenteral and/or oral antibiotics,and obvious clinical improvement was achieved with resolution of pulmonary and brain lesions on repeat imaging.CONCLUSION m NGS provided fast and precise pathogen detection of Nocardia.In disseminated nocardiosis,linezolid is an important alternative that can give a better outcome with the monitoring of linezolid serum concentrations and platelet count.

Diagnosis of cytomegalovirus encephalitis using metagenomic nextgeneration sequencing of blood and cerebrospinal fluid:A case report

BACKGROUND Cytomegalovirus(CMV)infections in the population are mostly subclinical,inapparent,or latent.However,it is rare in brain tissue.Most reported CMV encephalitis cases were patients with immunodeficiency.The diagnosis and detection rate of CMV encephalitis in patients with normal immune function needs to be further improved.CASE SUMMARY An 86-year-old male was admitted due to a sudden onset of unconsciousness for 3 h.The patient developed status epilepticus and was relieved after antiepileptic treatment.Encephalitis was considered due to the high signals of diffusionweighted imaging sequences in the right central region by magnetic resonance imaging.Metagenomic next-generation sequencing(mNGS)of blood and cerebrospinal fluid revealed CMV,with unique reads number being 614 and 1,respectively.Simultaneous quantitative PCR results showed CMV positive in blood samples and negative in cerebrospinal fluid samples.The patient was finally diagnosed as CMV encephalitis with status epilepticus.After the antiviral,hormonal,andγ-globulin pulse therapy,the patient’s condition improved,and he was finally discharged.CONCLUSION mNGS could be a reliable approach for the diagnosis of CMV encephalitis,with high efficiency,sensitivity,and specificity.

Successful surgical treatment of polybacterial gas gangrene confirmed by metagenomic next-generation sequencing detection:A case report

BACKGROUND We report on a case of Vibrio vulnificus(V.vulnificus)detected by metagenomics next-generation sequencing(mNGS)in a 53-year-old male patient with polymicrobial gas gangrene and successful treatment by surgery.This report raises awareness among dermatologists that when a patient is clinically suspected of a special type of pathogenic infection,the mNGS method should be preferred to identify the patient’s pathogen infection as soon as possible and then take effective treatment in time to save patients’lives.CASE SUMMARY A 53-year-old male who worked in the aquatic market complained of redness and swelling of the lower limbs,blisters and ulcers with fever for 3 d.We used mNGS to test the pathogens in ulcer secretions.The results were returned in 24 h and indicated:V.vulnificus,Fusobacterium necrophorum,Staphylococcus haemolyticus,Staphylococcus aureus,Streptococcus dysgalactiae and Klebsiella aerogenes.This patient was diagnosed with V.vulnificus infection.The emergency operation was performed immediately under combined lumbar and epidural anesthesia:Left leg expansion and exploration(August 10,2021).After surgery,we continued to use piperacillin sodium tazobactam sodium 4.5 g every 8 h and levofloxacin 0.5 g for anti-infection treatment.The patient underwent further surgery under lumbar anesthesia on August 17,2021 and August 31,2021:Left leg deactivation and skin grafting,negative pressure closed drainage and right thigh skin removal.After treatment,the transplanted flap survived.CONCLUSION We could confirm the diagnosis of Vibrio vulnificus infection within 24 h through mNGS detection and then immediately performed emergency surgery.

Application of metagenomic next-generation sequencing in the diagnosis of infectious diseases of the central nervous system after empirical treatment

BACKGROUND The diagnostic value of metagenomic next-generation sequencing(mNGS)in central nervous system(CNS)infectious diseases after empirical treatment has not been reported.AIM To investigate the diagnostic value of mNGS of cerebrospinal fluid(CSF)in the empirically treated CNS infectious diseases.METHODS A total of 262 CSF samples from patients with suspected CNS infections were collected between August 2020 and December 2021.Both mNGS and conventional methods were used for testing.The conventional methods included microbial culture,smear,polymerase chain reaction,etc.RESULTS Among 262 suspected cases,183 cases(69.84%)were diagnosed as CNS infection,including 86 cases of virus infection(47.00%),70 cases of bacterial infection(38.25%)and 27 cases of fungal infection(14.76%).The sensitivity and specificity of mNGS were 65.6%(95%CI:58.2%-72.3%)and 89.6%(95%CI:79.1%-95.3%),respectively.The PPV of mNGS was 94.5%(95%CI:88.6%-97.6%),and the NPV was 48.8%(95%CI:39.7%–57.9%).The pathogen detective sensitivity and accuracy of mNGS were higher than those of conventional methods(Sensitivity:65.6%vs 37.2%;P<0.001;Accuracy:72.0%vs 50%,P<0.001).The results showed that compared with conventional methods,mNGS technology was a more sensitive method for the diagnosis of CNS infection after empirical treatment.CONCLUSION mNGS can be a better method applied in the diagnosis of CNS infection after empirical treatment.

Review of the Clinical Applications of Metagenomic Next-Generation Sequencing in Bloodstream Infection

Bloodstream infection (BSI) is an important cause of morbidity and mortality worldwide. If we can make early diagnosis and start effective antibiotic treatment in time, the hospitalization time of patients with bloodstream infection can be significantly shortened. However, the current diagnosis of bloodstream infection cannot achieve the ideal therapeutic effect to a large extent because of the matrix effect of blood and the long turnaround time of blood culture. Therefore, a new detection method with a short turnaround time and high sensitivity is needed for the early diagnosis and timely treatment to improve the prognosis of patients. Metagenomic next-generation sequencing (mNGS) is a recently developed method for the comprehensive analysis of all microorganisms and genetic materials in clinical samples and is expected to be the main method for the early diagnosis of bloodstream infections. This review discusses the clinical application of mNGS in bloodstream infections. We also discuss technical challenges that need to be addressed to improve the diagnostic applicability of mNGS.

Usefulness of metagenomic next-generation sequencing in adenovirus 7-induced acute respiratory distress syndrome:A case report

BACKGROUND Direct metagenomic next-generation sequencing(mNGS)of clinical samples is an effective method for the molecular diagnosis of infection.However,its role in the diagnosis of patients with acute respiratory distress syndrome(ARDS)of an unknown infectious etiology remains unclear.CASE SUMMARY A 33-year-old man was admitted to our center for a cough and febrile sensation.Shortly after admission,the patient was diagnosed with ARDS and treated in the intensive care unit.Subsequently,chest computed tomography features suggested an infection.mNGS was performed and the results were indicative of an infection caused by adenovirus type 7.The patient recovered after receiving appropriate treatment.CONCLUSION mNGS is a promising tool for the diagnosis of ARDS caused by infectious agents.However,further studies are required to develop strategies for incorporating mNGS into the current diagnostic process for the disease.

Endoscopic ultrasound-guided fine-needle aspiration pancreatic adenocarcinoma samples yield adequate DNA for next-generation sequencing:A cohort analysis

BACKGROUND Genetic tests are increasingly performed for the management of unresectable pancreatic cancer.For genotyping aimed samples current guidelines recommend using core specimens,although based on moderate quality evidence.However,in clinical practice among the endoscopic ultrasound(EUS) guided tissue acquisition methods,fine needle aspiration(FNA) is the most widely performed.AIM To assess the adequacy for next generation sequencing(NGS) of the DNA yielded from EUS-FNA pancreatic adenocarcinoma(PDAC) samples.METHODS Between November 2018 and December 2021,105 patients with PDAC confirmed by EUS-FNA were included in the study at our tertiary gastroenterology center.Either 22 gauge(G) or 19G FNA needles were used.One pass was dedicated to DNA extraction.DNA concentration and purity(A260/280,A260/230) were assessed by spectrophotometry.We assessed the differences in DNA parameters according to needle size and tumor characteristics(size,location) and the adequacy of the extracted DNA for NGS(defined as A260/280 ≥ 1.7,and DNA yield:≥ 10 ng for amplicon based NGS,≥ 50 ng for whole exome sequencing [WES],≥ 100 ng for whole genome sequencing [WGS]) by analysis of variance and ttest respectively.Moreover,we compared DNA purity parameters across the different DNA yield categories.RESULTS Our cohort included 49% male patients,aged 67.02 ± 8.38 years.The 22G needle was used in 71%of the cases.The DNA parameters across our samples varied as follows:DNA yield:1289 ng(inter quartile range:534.75-3101),A260/280 = 1.85(1.79-1.86),A260/230 = 2.2(1.72-2.36).DNA yield was > 10 ng in all samples and > 100 ng in 93% of them(one sample < 50 ng).There were no significant differences in the concentration and A260/280 between samples by needle size.Needle size was the only independent predictor of A260/230 which was higher in the 22G samples(P =0.038).NGS adequacy rate was 90% for 19G samples regardless of NGS type,and for 22G samples it reached 89% for WGS adequacy and 91% for WES and amplicon based NGS.Samples with DNA yield > 100 ng had significantly higher A260/280(1.89 ± 0.32 vs 1.34 ± 0.42,P = 0.013).Tumor characteristics were not corelated with the DNA parameters.CONCLUSION EUS-FNA PDAC samples yield DNA adequate for subsequent NGS.DNA amount was similar between 22G and 19G FNA needles.DNA purity parameters may vary indirectly with needle size.

Metagenomic Insight Reveals the Microbial Structure and Function of the Full-Scale Coking Wastewater Treatment System:Gene-Based Nitrogen Removal

Microbial communities play crucial roles in pollutant removal and system stability in biological systems for coking wastewater(CWW)treatment,but a comprehensive understanding of their structure and functions is still lacking.A five month survey of four sequential bioreactors,anoxic 1/oxic 1/anoxic 2/oxic 2(A1/O1/A2/O2),was carried out in a full-scale CWW treatment system in China to elucidate operational performance and microbial ecology.The results showed that A1/O1/A2/O2 had excellent and stable performance for nitrogen removal.Both total nitrogen(TN;(17.38±6.89)mgL1)and ammonium-nitrogen(NH4 t-N;(2.10±1.34)mg·L^(-1))in the final biological effluent satisfied the Chinese national standards for CWW.Integrated analysis of 16S ribosome RNA(rRNA)sequencing and metagenomic sequencing showed that the bacterial communities and metagenomic function profiles of A1 and O1 shared similar functional structures,while those of A2 significantly varied from those of other bioreactors(p<0.05).The results indicated that microbial activity was strongly connected with activated sludge function.Nitrosospira,Nitrosomonas,and SM1A02 were responsible for nitrification during the primary anoxic-oxic(AO)stage and Azoarcus and Thauera acted as important denitrifiers in A2.Nitrogen cycling-related enzymes and genes work in the A1/O1/A2/O2 system.Moreover,the hao genes catalyzing hydroxylamine dehydrogenase(EC 1.7.2.6)and the napA and napB genes catalyzing nitrate reductase(EC 1.9.6.1)played important roles in the nitrification and denitrification processes in the primary and secondary AO stages,respectively.The mixed liquor suspended solids(MLSS)/total solids(TS),TN removal rate(RR),total organic carbon(TOC)(RR),and NH_(4)^(+)t-N(RR)were the most important environmental factors for regulating the structure of core bacterial genera and nitrogen-cycling genes.Proteobacteria were the potential main participants in nitrogen metabolism in the A1/O1/A2/O2 system for CWW treatment.This study provides an original and comprehensive understanding of the microbial community and functions at the gene level,which is crucial for the efficient and stable operation of the full-scale biological process for CWW treatment.