Maize requires arogenate dehydratase 2 for resistance to Ustilago maydis and plant development.

Maize (Zea mays) smut is a common biotrophic fungal disease caused by Ustilago maydis and leads to low maize yield. Maize resistance to U. maydis is a quantitative trait. However, the molecular mechanism underlying the resistance of maize to U. maydis is poorly understood. Here, we reported that a maize mutant caused by a single gene mutation exhibited defects in both fungal resistance and plant development. maize mutant highly susceptible to U. maydis (mmsu) with a dwarf phenotype forms tumors in the ear. A map-based cloning and allelism test demonstrated that 1 gene encoding a putative arogenate dehydratase/prephenate dehydratase (ADT/PDT) is responsible for the phenotypes of the mmsu and was designated as ZmADT2. Combined transcriptomic and metabolomic analyses revealed that mmsu had substantial differences in multiple metabolic pathways in response to U. maydis infection compared with the wild type. Disruption of ZmADT2 caused damage to the chloroplast ultrastructure and function, metabolic flux redirection, and reduced the amounts of salicylic acid (SA) and lignin, leading to susceptibility to U. maydis and dwarf phenotype. These results suggested that ZmADT2 is required for maintaining metabolic flux, as well as resistance to U. maydis and plant development in maize. Meanwhile, our findings provided insights into the maize response mechanism to U. maydis infection.

Genome-wide identification, stress- and hormone-responsive expression characteristics, and regulatory pattern analysis of Scutellaria baicalensis SbSPLs.

SQUAMOSA PROMOTER BINDING PROTEIN-LIKEs (SPLs) encode plant-specific transcription factors that regulate plant growth and development, stress response, and metabolite accumulation. However, there is limited information on Scutellaria baicalensis SPLs. In this study, 14 SbSPLs were identified and divided into 8 groups based on phylogenetic relationships. SbSPLs in the same group had similar structures. Abscisic acid-responsive (ABRE) and MYB binding site (MBS) cis-acting elements were found in the promoters of 8 and 6 SbSPLs. Segmental duplications and transposable duplications were the main causes of SbSPL expansion. Expression analysis based on transcriptional profiling showed that SbSPL1, SbSPL10, and SbSPL13 were highly expressed in roots, stems, and flowers, respectively. Expression analysis based on quantitative real-time polymerase chain reaction (RT‒qPCR) showed that most SbSPLs responded to low temperature, drought, abscisic acid (ABA) and salicylic acid (SA), among which the expression levels of SbSPL7/9/10/12 were significantly upregulated in response to abiotic stress. These results indicate that SbSPLs are involved in the growth, development and stress response of S. baicalensis. In addition, 8 Sba-miR156/157 s were identified, and SbSPL1-5 was a potential target of Sba-miR156/157 s. The results of target gene prediction and coexpression analysis together indicated that SbSPLs may be involved in the regulation of L-phenylalanine (L-Phe), lignin and jasmonic acid (JA) biosynthesis. In summary, the identification and characterization of the SbSPL gene family lays the foundation for functional research and provides a reference for improved breeding of S. baicalensis stress resistance and quality traits.

A MYB-related transcription factor ZmMYBR29 is involved in grain filling.

BACKGROUND: The endosperm serves as the primary source of nutrients for maize (Zea mays L.) kernel embryo development and germination. Positioned at the base of the endosperm, the transfer cells (TCs) of the basal endosperm transfer layer (BETL) generate cell wall ingrowths, which enhance the connectivity between the maternal plant and the developing kernels. These TCs play a crucial role in nutrient transport and defense against pathogens. The molecular mechanism underlying BETL development in maize remains unraveled. RESULTS: This study demonstrated that the MYB-related transcription factor ZmMYBR29, exhibited specific expression in the basal cellularized endosperm, as evidenced by in situ hybridization analysis. Utilizing the CRISPR/Cas9 system, we successfully generated a loss-of-function homozygous zmmybr29 mutant, which presented with smaller kernel size. Observation of histological sections revealed abnormal development and disrupted morphology of the cell wall ingrowths in the BETL. The average grain filling rate decreased significantly by 26.7% in zmmybr29 mutant in comparison to the wild type, which impacted the dry matter accumulation within the kernels and ultimately led to a decrease in grain weight. Analysis of RNA-seq data revealed downregulated expression of genes associated with starch synthesis and carbohydrate metabolism in the mutant. Furthermore, transcriptomic profiling identified 23 genes that expressed specifically in BETL, and the majority of these genes exhibited altered expression patterns in zmmybr29 mutant. CONCLUSIONS: In summary, ZmMYBR29 encodes a MYB-related transcription factor that is expressed specifically in BETL, resulting in the downregulation of genes associated with kernel development. Furthermore, ZmMYBR29 influences kernels weight by affecting the grain filling rate, providing a new perspective for the complementation of the molecular regulatory network in maize endosperm development.

Spatiotemporal dual-periodic soliton pulsation in a multimode fiber laser.

Spatiotemporal mode-locked (STML) fiber lasers have become a new platform for investigating nonlinear phenomena. In this work, spatiotemporal dual-periodic soliton pulsation (SDSP) is firstly observed in an STML fiber laser. It is found that in the SDSP, the long-period pulsations (LPPs) of different transverse modes are synchronous, while the short-period pulsations (SPPs) exhibit asynchronous modulations. The numerical simulation confirms the experimental results and further reveals that the proportion of transverse mode components can manipulate the periods of the LPP and SPP but does not affect the synchronous and asynchronous pulsations of different transverse modes. The obtained results bring the study of spatiotemporal dissipative soliton pulsation into the multi-period modulation stage, which helps to understand the complex spatiotemporal dynamics in STML fiber lasers and discover new dynamics in high-dimensional nonlinear systems.

Smart Target-Initiated Catalytic DNA Junction Circuit Amplification Strategy for the Ultrasensitive Electrochemiluminescence Detection of MicroRNA.

One of the highly attractive research directions in the electrochemiluminescence (ECL) field is how to regulate and improve ECL efficiency. Quantum dots (QDs) are highly promising ECL materials due to their adjustable luminescence size and strong luminous efficiency. MoS2 NSs@QDs, an ECL emitter, is synthesized via hydrothermal methods, and its ECL mechanism is investigated using cyclic voltammetry and ECL-potential curves. Then, a stable and vertical attachment of a triplex DNA (tsDNA) probe to the MoS2 nanosheets (NSs) is applied to the electrode. Next, an innovative ECL sensor is courageously empoldered for precise and ultrasensitive detection of target miRNA-199a through the agency of ECL-resonance energy transfer (RET) strategy and a dextrous target-initiated catalytic three-arm DNA junction assembly (CTDJA) based on a toehold strand displacement reaction (TSDR) signal amplification approach. Impressively, the ingenious system not only precisely regulates the distance between energy donor-acceptor pairs leave energy less loss and more ECL-RET efficiency, but also simplifies the operational procedure and verifies the feasibility of this self-assembly process without human intervention. This study can expand MoS2 NSs@QDs utilization in ECL biosensing applications, and the proposed nucleic acid amplification strategy can become a miracle cure for ultrasensitive detecting diverse biomarkers, which helps researchers to better study the tumor mechanism, thereby unambiguously increasing cancer cure rates and reducing the risk of recurrence.

Iva xanthiifolia leaf extract reduced the diversity of indigenous plant rhizosphere bacteria.

BACKGROUND: Iva xanthiifolia, native to North America, is now widely distributed in northeastern China and has become a vicious invasive plant. This article aims to probe the role of leaf extract in the invasion of I. xanthiifolia. METHODS: We collected the rhizosphere soil of Amaranthus tricolor and Setaria viridis in the invasive zone, the noninvasive zone and the noninvasive zone treated with extract from I. xanthiifolia leaf, and obtained I. xanthiifolia rhizosphere soil in the invasive zone. All wild plants were identified by Xu Yongqing. I. xanthiifolia (collection number: RQSB04100), A. tricolor (collection number: 831,030) and S. viridis (collection number: CF-0002-034) are all included in Chinese Virtual Herbarium ( https://www.cvh.ac.cn/index.php ). The soil bacterial diversity was analyzed based on the Illumina HiSeq sequencing platform. Subsequently, taxonomic analysis and Faprotax functional prediction were performed. RESULTS: The results showed that the leaf extract significantly reduced the diversity of indigenous plant rhizosphere bacteria. A. tricolor and S. viridis rhizobacterial phylum and genus abundances were significantly reduced under the influence of I. xanthiifolia or its leaf extract. The results of functional prediction showed that bacterial abundance changes induced by leaf extracts could potentially hinder nutrient cycling in native plants and increased bacterial abundance in the A. tricolor rhizosphere related to aromatic compound degradation. In addition, the greatest number of sensitive Operational Taxonomic Units (OTUs) appeared in the rhizosphere when S. viridis was in response to the invasion of I. xanthiifolia. It can be seen that A. tricolor and S. viridis have different mechanisms in response to the invasion of I. xanthiifolia. CONCLUSION: I. xanthiifolia leaves material has potential role in invasion by altering indigenous plant rhizosphere bacteria.

Defective kernel 66 encodes a GTPase essential for kernel development in maize.

The mitochondrion is a semi-autonomous organelle that provides energy for cell activities through oxidative phosphorylation. In this study, we identified a defective kernel 66 (dek66)-mutant maize with defective kernels. We characterized a candidate gene, DEK66, encoding a ribosomal assembly factor located in mitochondria and possessing GTPase activity (which belongs to the ribosome biogenesis GTPase A family). In the dek66 mutant, impairment of mitochondrial structure and function led to the accumulation of reactive oxygen species and promoted programmed cell death in endosperm cells. Furthermore, the transcript levels of most of the key genes associated with nutrient storage, mitochondrial respiratory chain complex, and mitochondrial ribosomes in the dek66 mutant were significantly altered. Collectively, the results suggest that DEK66 is essential for the development of maize kernels by affecting mitochondrial function. This study provides a reference for understanding the impact of a mitochondrial ribosomal assembly factor in maize kernel development.

Identification of three capsule depolymerases in a bacteriophage infecting Klebsiella pneumoniae capsular types K7, K20, and K27 and therapeutic application.

BACKGROUND: Klebsiella pneumoniae capsular types K1, K2, K5, K20, K54, and K57 are prevalent hypervirulent types associated with community infections, and worrisomely, hypervirulent strains that acquired drug resistance have been found. In the search for alternative therapeutics, studies have been conducted on phages that infect K. pneumoniae K1, K2, K5, and K57-type strains and their phage-encoded depolymerases. However, phages targeting K. pneumoniae K20-type strains and capsule depolymerases capable of digesting K20-type capsules have rarely been reported. In this study, we characterized a phage that can infect K. pneumoniae K20-type strains, phage vB_KpnM-20. METHODS: A phage was isolated from sewage water in Taipei, Taiwan, its genome was analyzed, and its predicted capsule depolymerases were expressed and purified. The host specificity and capsule-digesting activity of the capsule depolymerases were determined. The therapeutic effect of the depolymerase targeting K. pneumoniae K20-type strains was analyzed in a mouse infection model. RESULTS: The isolated Klebsiella phage, vB_KpnM-20, infects K. pneumoniae K7, K20, and K27-type strains. Three capsule depolymerases, K7dep, K20dep, and K27dep, encoded by the phage were specific to K7, K20, and K27-type capsules, respectively. K20dep also recognized Escherichia coli K30-type capsule, which is highly similar to K. pneumoniae K20-type. The survival of K. pneumoniae K20-type-infected mice was increased following administration of K20dep. CONCLUSIONS: The potential of capsule depolymerase K20dep for the treatment of K. pneumoniae infections was revealed using an in vivo infection model. In addition, K7dep, K20dep, and K27dep capsule depolymerases could be used for K. pneumoniae capsular typing.

[Identification of key enzyme genes involved in biosynthesis pathways of lignan and lignin in Eucommia ulmoides based on transcriptome assembly].

Lignan is the main medicinal component of Eucommia ulmoides, and lignin is involved in the defense of plants against diseases and insect pests.They are synthesized from coniferyl alcohol with the help of dirigent(DIR) and peroxidase(POD), respectively.In this study, transcriptome assembly of stems and leaves of E.ulmoides was performed, yielding 112 578 unigenes.Among them, 70 459 were annotated in seven databases.A total of 59 unigenes encodes 11 key enzymes in the biosynthesis pathways of lignin and lignin, of which 11 encode POD and 8 encode DIR.A total of 13 unigenes encoding transcription factors are involved in phenylpropanoid metabolism. Compared with leaves of E.ulmoides, 7 575 unigenes were more highly expressed in stems, of which 462 were involved in phenylpropanoid biosynthesis.Our results extend the public transcriptome dataset of E.ulmoides, which provide valuable information for the analysis of biosynthesis pathways of lignan and lignin in E.ulmoides and lay a foundation for further study on the functions and regulation mechanism of key enzymes in lignan and lignin biosynthesis pathways.

Switchable and spacing tunable dual-wavelength spatiotemporal mode-locked fiber laser.

We report a switchable and spacing tunable dual-wavelength spatiotemporal mode-locked (STML) laser based on the multimode interference filtering effect in an all-fiber linear cavity. The dual-wavelength STML operations combined with different pulse patterns are achieved. By adjusting the polarization controllers, the dual-wavelength STML pulses can be switched to single wavelength operation, which is tunable up to 35 nm under certain pump powers. Moreover, the dual-wavelength spacing can also be tuned from 8 nm to 22 nm. The obtained results contribute to understanding and exploring the spatiotemporal characteristics operating in the multi-wavelength regime of STML fiber lasers. All-fiber STML lasers with lasing wavelength tunability and flexibility may have applications in the fields of optical communications and optical measurements.

The novel E-subgroup pentatricopeptide repeat protein DEK55 is responsible for RNA editing at multiple sites and for the splicing of nad1 and nad4 in maize.

BACKGROUND: Pentatricopeptide repeat (PPR) proteins compose a large protein family whose members are involved in both RNA processing in organelles and plant growth. Previous reports have shown that E-subgroup PPR proteins are involved in RNA editing. However, the additional functions and roles of the E-subgroup PPR proteins are unknown. RESULTS: In this study, we developed and identified a new maize kernel mutant with arrested embryo and endosperm development, i.e., defective kernel (dek) 55 (dek55). Genetic and molecular evidence suggested that the defective kernels resulted from a mononucleotide alteration (C to T) at + 449 bp within the open reading frame (ORF) of Zm00001d014471 (hereafter referred to as DEK55). DEK55 encodes an E-subgroup PPR protein within the mitochondria. Molecular analyses showed that the editing percentage of 24 RNA editing sites decreased and that of seven RNA editing sites increased in dek55 kernels, the sites of which were distributed across 14 mitochondrial gene transcripts. Moreover, the splicing efficiency of nad1 introns 1 and 4 and nad4 intron 1 significantly decreased in dek55 compared with the wild type (WT). These results indicate that DEK55 plays a crucial role in RNA editing at multiple sites as well as in the splicing of nad1 and nad4 introns. Mutation in the DEK55 gene led to the dysfunction of mitochondrial complex I. Moreover, yeast two-hybrid assays showed that DEK55 interacts with two multiple organellar RNA-editing factors (MORFs), i.e., ZmMORF1 (Zm00001d049043) and ZmMORF8 (Zm00001d048291). CONCLUSIONS: Our results demonstrated that a mutation in the DEK55 gene affects the mitochondrial function essential for maize kernel development. Our results also provide novel insight into the molecular functions of E-subgroup PPR proteins involved in plant organellar RNA processing.

DEK43 is a P-type pentatricopeptide repeat (PPR) protein responsible for the Cis-splicing of nad4 in maize mitochondria.

Mitochondria, the main energy transducers in plant cells, require the proper assembly of respiratory chain complexes I-V for their function. The NADH dehydrogenase 4 (nad4) gene encodes mitochondrial respiratory chain complex I subunit IV, but the mechanism underlying nad4 transcript splicing is unclear. Here, we report that the P-type pentatricopeptide repeat (PPR) protein DEFECTIVE KERNEL 43 (DEK43) is responsible for cis-splicing of the nad4 transcript in maize. We demonstrate that DEK43 localizes to both the nucleus and mitochondria. The mutation of Dek43 resulted in embryo-lethal and light-colored defective kernels. Among the 22 mitochondrial group II introns, the splicing efficiency of nad4 introns 1 and 3 was reduced by up to 50% compared to the wild type. The levels of complex I and supercomplex I+III2 were also reduced in dek43. Furthermore, in-gel NADH dehydrogenase assays indicated that the activities of these complexes were significantly reduced in dek43. Further, the mitochondrial ultrastructure was altered in the mutant. Together, our findings indicate that DEK43, a dual-localized PPR protein, plays an important role in maintaining mitochondrial function and maize kernel development.

[Identification of key enzyme genes involved in biosynthesis of steroidal saponins and analysis of biosynthesis pathway in Polygonatum cyrtonema].

Steroidal saponins, which are the characteristic and main active constituents of Polygonatum, exhibit a broad range of pharmacological functions, such as regulating blood sugar, preventing cardiovascular and cerebrovascular diseases and anti-tumor. In this study, we performed RNA sequencing(RNA-Seq) analysis for the flowers, leaves, roots, and rhizomes of Polygonatum cyrtonema using the BGISEQ-500 platform to understand the biosynthesis pathway of steroidal saponins and study their key enzyme genes. The assembly of transcripts for four tissues generated 129 989 unigenes, of which 88 958 were mapped to several public databases for functional annotation, 22 813 unigenes were assigned to 53 subcategories and 64 877 unigenes were annotated to 136 pathways in KEGG database. Furthermore, 502 unigenes involved in the biosynthesis pathway of steroidal saponins were identified, of which 97 unigenes encoding 12 key enzymes. Cycloartenol synthase, the first key enzyme in the pathway of phytosterol biosynthesis, showed conserved catalytic domain and substrate binding domain based on sequence analysis and homology modeling. Differentially expressed genes(DEGs) were identified in rhizomes as compared to other tissues(flowers, leaves or roots).The 2 437 unigenes annotated by KEGG showed rhizome-specific expression, of which 35 unigenes involved in the biosynthesis of steroidal saponins. Our results greatly extend the public transcriptome dataset of Polygonatum and provide valuable information for the identification of candidate genes involved in the biosynthesis of steroidal saponins and other important secondary metabolites.

[Transcriptome analysis of venom gland and identification of functional genes for snake venom protein in Agkistrodon acutus].

Agkistrodon acutus is a traditional Chinese herb medicine which has immunological regulation,anti-tumor,anti-inflammatory and analgesic effects,which is mainly used for the treatment of rheumatoid arthritis,ankylosing spondylitis,sjogren's syndrome and tumors. In order to excavate more important functional genes from A. acutus,the transcriptome of the venom gland was sequenced by the Illumina Hi Seq 4000,and 32 862 unigenes were assembled. Among them,26 589 unigenes were mapped to least one public database. 2 695 unigenes were annotated and assigned to 62 TF families,and 5 920 SSR loci were identified. The majority of mapped unigenes was from Protobothrops mucrosquamatus in the NR database,which revealed their closest homology. Three secretory phospholipase A_2 with different amino acid sequences showed similar spatial structures and all had well-conserved active sites. The 3 D structural models of C-type lectin showed conserved glycosylation binding sites( Asn45). This study will lay the foundation for the further study of the function of snake venom protein,and promoting the development and utilization of genome resources from A. acutus.

[Cloning and characterization of chalcone synthase and chalcone isomerase genes in Arisaema heterophyllum].

Chalcone synthase( CHS) and chalcone isomerase( CHI) are key enzymes in the biosynthesis pathway of flavonoids. In this study,unigenes for CHS and CHI were screened from the transcriptome database of Arisaema heterophyllum. The open reading frame( ORFs) of chalcone synthase( Ah CHS) and chalcone isomerase( Ah CHI) were cloned from the plant by RT-PCR. The physicochemical properties,expression and structure characteristics of the encoded proteins Ah CHS and Ah CHI were analyzed. The ORFs of Ah CHS and Ah CHI were 1 176,630 bp in length and encoded 392,209 amino acids,respectively. Ah CHS functioned as a symmetric homodimer. The N-terminal helix of one monomer entwined with the corresponding helix of another monomer. Each CHS monomer consisted of two structural domains. In particular,four conserved residues define the active site. The tertiary structure of Ah CHI revealed a novel open-faced ß-sandwich fold. A large ß-sheet( ß4-ß11) and a layer of α-helices( α1-α7) comprised the core structure. The residues spanning ß4,ß5,α4,and α6 in the three-dimensional structure were conserved among CHIs from different species. Notably,these structural elements formed the active site on the protein surface,and the topology of the active-site cleft defined the stereochemistry of the cyclization reaction. The homology comparison showed that Ah CHS had the highest similarity to the CHS of Anthurium andraeanum,while Ah CHI had the highest similarity to the CHI of Paeonia delavayi. This study provided the basis for the functional study of Ah CHS and Ah CHI and the further study on plant flavonoid biosynthesis pathway.

Comprehensive risk assessment and source identification of selected heavy metals (Cu, Cd, Pb, Zn, Hg, As) in tidal saltmarsh sediments of Shuangtai Estuary, China.

Heavy metals do not degrade and can remain in the environment for a long time. In this study, we analyzed the effects of Cu, Cd, Pb, Zn, Hg, and As, on environmental quality, pollutant enrichment, ecological hazard, and source identification of elements in sediments using data collected from samples taken from Shuangtai tidal wetland. The comprehensive pollution indices were used to assess environmental quality; fuzzy similarity analysis and geoaccumulation index were used to analyze pollution accumulation; correlation matrix, principal component analysis, and clustering analysis were used to analyze pollution source; environmental risk index and ecological risk index were used to assess ecological risk. The results showed that the environmental quality was either clean or almost clean. Pollutant enrichment analysis showed that the four sub-regions had similar pollution-causing metals to the background values of the soil element of the Liao River Plain, which were ranked according to their similarity. Source identification showed that all the elements were correlated. Ecological hazard analysis showed that the environmental risk index in the study area was less than zero, posing a low ecological risk. Ecological risk of the six elements was as follows: As > Cd > Hg > Cu > Pb > Zn.

Utilizing Machine Learning to Identify Biomarkers of Endoplasmic Reticulum Stress and Analyze Immune Cell Infiltration in Parkinson's Disease.

The neurodegenerative disorder known as Parkinson's disease (PD) affects many people. The objective of this investigation was to examine the relationship between immune system infiltration, ATP-binding cassette transporter subfamily A member 7 (ABCA7) and TBL2 as well as potential therapeutic targets for the identification of PD associated to endoplasmic reticulum (ER) stress. First, we obtained PD data through GEO and divided it into two sets: a training set (GSE8397) plus a set for validation (GSE7621). Functional enrichment analysis was performed on a set of DEGs that overlapped with genes involved in endoplasmic reticulum stress. To identify genes of PD linked with endoplasmic reticulum stress, we employed random forest (RF) along with the least absolute shrinkage and selection operator (LASSO) logistic regression. Spearman's rank correlation analysis was then used to find associations among diagnostic markers with immune cell penetration. A grand total of 2 stress-related endoplasmic reticulum signature transcripts were identified. ABCA7 and TBL2 were shown to have diagnostic potential for PD and immune infiltrating cells have a role in the etiology of the disease. Additionally, resting CD4 memory, plasma cells, and NK cells overall exhibited positive associations with ABCA7, whereas triggered macrophages, T cells with active CD4 memory, activating NK cells, T cells with activated CD4 naive, engaged NK cells, and neutrophils all had adverse interactions with ABCA7. Overall, ABCA7 together with TBL2 have diagnostic utility for PD, and several types of immune cells, especially macrophages, may be involved in the development and progression of the disease.

Investigation of carbapenem-resistant Klebsiella pneumoniae in Taiwan revealed strains co-harbouring blaNDM and blaOXA-48-like and a novel plasmid co-carrying blaNDM-1 and blaOXA-181.

The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) is related to the transmission of carbapenemase genes. Strains carrying more than one carbapenemase with a broadened spectrum of antibiotic resistance have been detected, which is concerning. Although blaKPC-encoding ST11-KL47/KL64 strains are dominant, other clones are emerging. This study investigated 137 CRKP from patients' blood samples in Taiwan. Polymerase chain reaction (PCR) was used to identify carbapenemase genes and capsular (KL) types. Most strains (56%, 77/137) possessed blaKPC alone; however, 12% (17/137) carried blaNDM+blaOXA-48-like and these strains showed high resistance to imipenem and meropenem. Strains carrying blaNDM+blaOXA-48-like predominantly belonged to KL51 (n=15), followed by KL64 (n=1) and KL47 (n=1). Whole-genome sequencing of one KL51 strain indicated that blaNDM-4 and blaOXA-181 are carried on two different plasmids. PCR was performed using specific primers located in these plasmids, and all blaNDM+blaOXA-48-like-encoding strains except the KL64 strain were considered to carry the two abovementioned plasmids. Genome analysis for the KL64 strain revealed that blaNDM-1 and blaOXA-181 are encoded in one plasmid. Notably, the KL51 blaOXA-181 plasmid shared high sequence similarity with the KL64 blaNDM-1+blaOXA-181 plasmid, except the KL64 plasmid comprised a 15,040-bp insertion encoding blaNDM-1. The data revealed KL51 as a predominant KL type carrying blaNDM-4+blaOXA-181, and identified a novel plasmid carrying blaNDM-1+blaOXA-181, highlighting the spread of specific plasmids and clones of CRKP in Taiwan.

[Value of cytopathology in endobronchial ultrasound-guided transbronchial needle aspiration].

OBJECTIVE: To evaluate the role of cytopathology in endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for lung tumor diagnosis and staging. METHODS: Two-hundred consecutive cases of lung tumor with EBUS-TBNA performed during the period from April, 2009 to September, 2010 in Shanghai Cancer Hospital were retrospectively reviewed. The cytologic diagnoses were categorized as non-diagnostic, negative, suspicious and malignant. When available, cell block preparation and immunohistochemistry were performed. On the 22 positive cases diagnosed by on-site evaluation, epidermal growth factor receptor (EGFR) mutation study was carried out. RESULTS: In the 200 cases of cytology specimens, 122 cases (69.3%) were diagnosed as malignant, 42 cases (23.9%) as benign and 12 cases (6.8%) as suspicious for malignancy. The non-diagnostic rate was 12.0% (24/200). Amongst the 200 cases studied, 140 cases (70.0%) had histologic correlation available (via core biopsy, mediastinoscopic biopsy or surgical excision). The sensitivity and specificity of EBUS-TBNA cytologic diagnoses were 94.4% and 100%, when using histopathologic findings and clinical follow-up data as gold standard. The cell block preparation and immunohistochemistry were useful in subtyping and diagnosis of extrathoracic malignancy. EGFR mutations were detected in 8 cytology samples (36.4%). CONCLUSIONS: EBUS-TBNA is a sensitive and specific tool for diagnosis and staging of lung cancer. The cytology samples can be used for further ancillary investigations including cell block preparation, immunohistochemistry and molecular studies.