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Cronobacter sakazakii is an opportunistic pathogen that can cause severe infections. Serotyping provides a basis for the categorization of bacterial strains and is an important tool for epidemiological and surveillance purposes. In this study, of the 135 Cronobacter strains tested initially, 119 were identified as C. sakazakii and used. A serotyping scheme for C. sakazakii that classifies strains based on their different O antigens was developed. Seven antisera that exhibited high agglutinin titers (>640) were produced. O2 and O6 antisera were specific for their homologous strains, O4 and O7 antisera gave heterologous titers with O1 and O6 antigens, respectively, and O1, O3, and O5 antisera cross-reacted with each other and require preabsorption with the other two antigens. All of these 119 C. sakazakii strains were clearly assigned to these seven serotypes. O1 and O2 are the dominant serotypes, comprising 69.7% of the isolates. We also characterized the O-antigen gene clusters using restriction fragment length polymorphism (RFLP). The grouping of C. sakazakii strains based on their RFLP banding patterns correlated well with the grouping of strains based on our serotyping scheme. The serotype scheme presented here could prove to be a useful tool for serotyping C. sakazakii isolates.

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Tuberculous pleurisy is one of the most common types of extrapulmonary tuberculosis, but its diagnosis remains difficult. In this study, we report for the first time on the detection of cell-free Mycobacterium tuberculosis DNA in pleural effusion and an evaluation of a newly developed molecular assay for the detection of cell-free Mycobacterium tuberculosis DNA. A total of 78 patients with pleural effusion, 60 patients with tuberculous pleurisy, and 18 patients with alternative diseases were included in this study. Mycobacterial culture, the Xpert MTB/RIF assay, the adenosine deaminase assay, the T-SPOT.TB assay, and the cell-free Mycobacterium tuberculosis DNA assay were performed on all the pleural effusion samples. The cell-free Mycobacterium tuberculosis DNA assay and adenosine deaminase assay showed significantly higher sensitivities of 75.0% and 68.3%, respectively, than mycobacterial culture and the Xpert MTB/RIF assay, which had sensitivities of 26.7% and 20.0%, respectively (P Ͻ 0.01). All four of these tests showed good specificities: 88.9% for the adenosine deaminase assay and 100% for the remaining three assays. The T-SPOT.TB assay with pleural effusion showed the highest sensitivity of 95.0% but the lowest specificity of 38.9%. The cell-free Mycobacterium tuberculosis DNA assay detected as few as 1.25 copies of IS6110 per ml of pleural effusion and showed good accordance of the results between repeated tests (r ϭ 0.978, P ϭ 2.84 ϫ 10 Ϫ10 ). These data suggest that the cell-free Mycobacterium tuberculosis DNA assay is a rapid and accurate molecular test which provides direct evidence of Mycobacterium tuberculosis etiology.KEYWORDS Mycobacterium tuberculosis, cell-free DNA, pleural effusion T uberculous pleurisy (TP) is one of the most common extrapulmonary manifestations of tuberculosis, but its diagnosis is quite challenging (1). The definite diagnosis of TP is made by detecting Mycobacterium tuberculosis from the pleural effusion (PE), sputum, or pleural tissue (1, 2). However, due to the paucity of M. tuberculosis organisms in PE, culture and molecular tests like the Xpert MTB/RIF assay show poor sensitivities (3-5).Other assays for the immunochemical biomarkers mostly reported in PE are the adenosine deaminase assay (ADA), the interferon gamma (IFN-␥) assay, and IFN-␥ release assays (IGRAs). Adenosine deaminase and IFN-␥ are believed to be released during the immune response triggered by the presence of mycobacterial antigens in the pleural cavity. Recent meta-analyses show that adenosine deaminase and IFN-␥ appear to be relatively accurate biomarkers for TP diagnosis. However, a wide range of diagnostic cutoff values may cause heterogeneity (6-9). IGRAs are T-cell-based assays that measure IFN-␥ release by sensitized T cells in response to M. tuberculosis-specific antigens. The presence of IFN-␥ is a strong indicator of M. tuberculosis infection, but the value of IGRAs for the diagnosis of TP is still controversial. Some studies show that

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(high resistance) processes of unipolar switching devices depend on the amplitude of the applied voltage rather than its polarity. This occurs because the formation and rupture of the metal nanofi lament (MNF) in unipolar switching is triggered by Joule heating (which is polarity-insensitive). For bipolar switching devices on the other hand, the polarity of the applied voltage must be opposite for SET and RESET, as this mode operates via the reversible voltage-dependent drift of oxygen vacancies and ions. [9][10][11][12][13] Hence, understanding the fundamental microstructural and compositional evolution of the fi lament and conduction path (mainly oxygen vacancies) in the dielectric layers is the key to controlling and optimizing RRAM devices both in terms of performance and reliability.Previous studies using physical microscopy techniques have shown that the shape of MNFs can be conical or hyperboloidal and the number of MNFs formed in the dielectric stack can vary from one device to another. [14][15][16][17] The structural and compositional evolution of the conduction paths and fi laments has been studied in various materials systems, including TiO 2 /Pt, ZnO/Pt, SiO 2 /Ag, a-TaO 2-x /Pt, and SrTiO 3 /Ag. [18][19][20][21][22] Our study on Ni/HfO 2 /SiO x /n + Si-based (i.e., MIS) RRAM is crucial because this material system is the most obvious potential candidate for commercial RRAM devices, as it is based on the established silicon device CMOS platform. In this study, we designed an asymmetric test structure for in situ transmission electron microscope (TEM) characterization, electrical testing, and chemical analysis with nanometer spatial precision. The test structure comprises a Ni top electrode and HfO 2 /SiO x dielectric layers on an n + doped Si substrate (doping concentration N D ≈10 19 cm −3 ). For our sample, the conventional (100) Si wafers were used as the starting substrate. The HfO 2 / SiO x dielectric layers were fabricated through a precisely controlled rapid thermal annealing process under 700 °C and N 2 ambient. Based on this test structure, we carried out a structural and compositional nanoscale characterization of the stressed devices in both the SET and RESET states. Our study provides suffi cient evidence to quantify the role of the top Ni electrode and its partial migration toward the dielectric and Si substrate for SET and RESET sweep conditions. The evolution of the MNF shape and its chemical composition in the dielectric layers is studied here, as these fi laments are the critical features that determine RRAM device reliability and scalability.The layout of the fabricated test structure is shown in Figure 1 a,b. The Ni (100 nm)/HfO 2 (3 nm)/SiO x (3 nm)/n + Si stack blanket wafer was prepared into a comb-shaped structure by focused ion beam (FIB) milling with in situ liftoff and low-energy ion cleaning. The resultant test structures have multiple "isolated" test units which were mounted to a grounded Although the resistive switching phenomenon in dielectric layers was fi rst documented...

Parasitic infections are a major public health concern affecting millions of people universally. This review elaborates on the potential impacts of plants and their bioactive components that have been widely used in the cure of several parasitic infections of poultry. The medicinal importance of natural herbs depends upon their bioactive ingredients, which are originated from crude plants, consequently leading to the specific action on the body. Due to the limited availability of effective drugs and high cost, the development of drug resistance in several harmful parasites and microbes leads to huge economic losses in the poultry industry. This will impose the development of innovative sources for drugs to overwhelm the therapeutic failure. Moreover, the environment-friendly feed additives which can be applied as a substitute to antibiotic growth promoters (AGP) for broilers were proven. The application of natural products with therapeutic characteristics is an ancient practice that is appropriately gaining more acceptance. Globally, it is assessed that some 20,000 species of higher plants are used medicinally, although traditional medicine has a scarcity of knowledge on its efficiency and wellbeing. This review explores the usage of medicinal herbs for parasitic infections, emphasizing the recent knowledge available while detecting the research gaps which may be explored to find the usage of herbal medicines for parasitic infections in poultry. In conclusion, herbal medicines are the effective source of prime components for drug detection and the formation of phytopharmaceuticals in the control of devastating parasitic infections. There is a prerequisite to applying the traditional medicine information in clinical applications via value addition.