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Recently, much research has been published on the hydrothermal liquefaction (HTL) of microalgae to form bio-crude, which can be further upgraded into sustainable 3 rd generation biofuels. However, most of these studies have been conducted in batch reactors, which are not fully applicable to large-scale industrial production. In this investigation an inexpensive laboratory scale continuous flow system was designed and tested for the liquefaction of microalgae produced during wastewater treatment. The system was operated at a range of temperatures (300 °C–340 °C) and flow rates (3–7 mL min − 1 ), with the feed being delivered using high pressure N 2 rather than a mechanical pump. The design incorporated the in-situ collection of solids through a double tube design. The algae was processed at 5 wt% and the results were compared to those from a batch reactor operated at equivalent conditions. By combining high heating rates with extended reaction times, the continuous system was able to yield significantly enhanced bio-crude yields compared to the batch system. This demonstrates the need for inexpensive continuous processing in the lab, to aid in scale up decision making. [ABSTRACT FROM AUTHOR]

Abstract: DNA microarrays have proven extraordinarily powerful for differential expression studies across thousands of genes in a single experiment. Microarrays also have the potential for clinical applications, including the detection of infectious and immunological diseases and cancer, if they can be rendered both reliable and cost-effective. Here we report the first practical application of an active microarray based on integrated circuit technology, completely obviating the need for external measurement instrumentation while employing protocols compatible with traditional fluorescence-based surface bioassays. In a gene expression biodosimetry study, we determine the differential activity of genes from leucocytes in irradiated human blood. Quantum dots are used as fluorescence labels to realize filterless, time-gated fluorescence detection on an active complementary metal-oxide-semiconductor (CMOS) microarray with 100-pM sensitivity. Improvements in surface chemistry should allow sensitivities that approach the microarray hardware limit of less than 10pM. Techniques for covalent attachment of DNA capture strands to the CMOS active microarrays allow integrated sensors to be placed in immediate proximity to hybridized analyte strands, maximizing photon collection efficiencies. [ABSTRACT FROM AUTHOR]

BACKGROUND: Interleukin (IL)-10 plays an important role in down-regulating the immune response to filarial parasites. The goal of this study was to characterize the predominant cellular source of IL-10 in human filarial infections. METHODS: Multicolor flow cytometry was used to determine the frequencies of IL-10 production from various lymphocyte populations in the circulation of 23 patients with filarial infections and 8 uninfected control subjects. RESULTS: The frequencies of cells spontaneously producing IL-10 was significantly greater in filaria-infected patients than in uninfected control subjects (geometric mean, 93 vs. 18 IL-10-producing cells/100,000 peripheral blood mononuclear cells; P = .03). Most IL-10-producing cells in filaria-infected patients were T cells, with CD4(+) and CD8(+) cells accounting for 48% and 27%, respectively, of all IL-10-producing cells; CD19(+) B cells, CD14(+) monocytes, and CD56(+) NK cells accounted for 10%, 8%, and 7%, respectively. Surprisingly, only 12% of the IL-10-producing CD3(+)CD4(+) cells were CD25(+). Seventy-seven percent of IL-10-producing CD4(+) T cells stained negatively for both IL-4 and interferon (IFN)-gamma, 22% were positive for IL-4, and <1% were positive for IFN-gamma. CONCLUSIONS: These experiments demonstrate that the most frequent producers of IL-10 in human filarial infections are CD4(+) T cells, many of which are skewed toward a type 2 phenotype and most of which are not CD25(+). Copyright © 2008 Infectious Diseases Society of America [ABSTRACT FROM AUTHOR]

A dense, homogeneous and crack-free ferroelectric PZT thin film with (100)-preferred orientation was produced using the sol-gel method. The volume fraction α(100) of (100)-oriented grains in the PZT film was calculated [α(100) ≈ 80%] from XRD of the PZT thin film and powder. The PZT thin film exhibits an open polarization vs. electric field loop and a low leakage current density from 10-8 A/cm2 to 10-7 A/cm2. The electrical conduction data were fit to a Schottky-emission model with deep traps from 100 kV/cm to 250 kV/cm. A modified capacitance model was introduced that adds electrical domain capacitance based on a metal-ferroelectric-metal (MFM) system with Schottky contacts. The model reproduces the observed non-linear capacitance vs. voltage behavior of the film. [ABSTRACT FROM AUTHOR]

Coherent diffraction microscopy determines the three-dimensional (3D) structure of a noncrystalline sample by acquiring a set of diffraction patterns at multiple sample orientations. In order to achieve a high spatial resolution, it usually requires a large number of diffraction patterns with small increments of tilt angles. However, this is not easily attainable for biological or other radiation-sensitive samples due to the radiation damage issue. With the constraint that only a limited number of diffraction patterns is available, a new method is proposed to optimize the effect of these data for three-dimensional image reconstruction. The method combines the concepts of selecting angles with a constant slope increment, the pseudopolar Fourier transform, and the guided hybrid input-output method for direct 3D phase retrieval. Based on simulated and experimental data, it is shown that the proposed method has a better accuracy than some existing three-dimensional image reconstruction techniques. The method is also examined for its stability and consistency by reducing data points used for image reconstruction. The relationship between the number of diffraction patterns used and the accuracy of the reconstructed images is also studied. [ABSTRACT FROM AUTHOR]

Background Conformational viral proteins potentially play an important role in the immunobiology of acute hepatitis C virus (HCV) infection and may enable earlier antibody detection. Materials and Methods HCV RNA was detected using nucleic acid testing. Early antibody production was evaluated using three enzyme immunoassays (EIAs) containing antigenic proteins not present in licensed EIAs. Respectively, these contained: (1) multiple-epitope fusion antigen (MEFA) 7·1-NS3/4a, (2) F and Core, and (3) E1/E2 proteins. NS3/4a is a conformational antigen retaining protease and helicase enzymatic activities. MEFA 7·1 contains the linear epitopes used in licenced EIAs, including the latest EIA-3·0, in combination with genotype 1–3 specific epitopes. Forty-two RNA positive, EIA-3·0 negative samples, including two persistently serosilent cases, were used to evaluate these research EIAs. As controls, 54 EIA-3·0 negative/RNA negative and three HCV RNA+/antibody positive specimens were included. Results Only the MEFA 7·1-NS3/4a EIA was positive in seven (17%) of the 42 HCV RNA + specimens, in all three EIA-3·0 positive controls but in none of 54 EIA-3·0 negative/HCV RNA negative controls. Notably, six of the seven (86%) specimens had evidence of active hepatitis (ALT > 210 IU/l). The two serosilent cases were research EIA negative. Conclusion A novel EIA with conformational and linear epitopes detected HCV antibodies in 17% of viraemic specimens missed by the standard reference EIA-3·0. Our research EIA appears to detect HCV antibodies closer to the initiation of acute hepatitis. Given that the average RNA-positive, antibody-negative window period is ∼56·4 days, this 17% yield would translate into a ∼10-day earlier detection of antibodies. [ABSTRACT FROM AUTHOR]

(1 – n – m)LiCo0.8Ni0.2O2 system was synthesized using the sol–gel method. Stoichiometric weights of the LiNO3, Mn(Ac)2 · 4H2O, Co(Ac)2 · 4H2O, Ni(NO3)2 · 6H2O for preparing of 28 samples have been used as starting materials of lithium, magnesium, cobalt and nickel, in 28 samples of (1 – n – m)LiCo0.8Ni0.2O2, respectively. We exhibited "Li1.333Ni0.4Co0.267Mn0.333O2" is the best composition for cathode material among those compositions. Obviously, the used weight of cobalt in this sample is lower compared with LiCoO2 that is an advantage in view point of cost and toxic problem. Charge–discharge characteristics of the mentioned cathode materials were investigated by performing cycle tests in the range of 2.2–4.5 V. Our results confirmed, although these kind systems can help for removing the disadvantage of cobalt which mainly is its cost and toxic, the performance of these kind systems are similar to LiCoO2 cathode material. [ABSTRACT FROM AUTHOR]

Head and neck squamous cell carcinoma (HNSCC) represents the 8th most common cancer worldwide.1 However, survival rates remain low at ≈50%, despite standard first-line treatment with the immune checkpoint inhibitor (ICI) pembrolizumab (PEMBRO) ± chemotherapy.2 Recombinant interleukin-2 (IL-2) is associated with improved overall survival (OS) in HNSCC patients.3 Research has shown that high levels of tumor-infiltrating lymphocytes are prognostic of disease-free survival in this patient population. Bempegaldesleukin (BEMPEG; NKTR-214), a first-in-class immunostimulatory IL-2 cytokine prodrug, is engineered to deliver a controlled, sustained, and preferential signal to the clinically validated IL-2 pathway to selectively stimulate antitumor responses. Earlier studies of BEMPEG in combination with ICIs evaluated in patients with immune-sensitive cancers have shown the potential to increase and deepen treatment responses vs historical rates for ICIs alone.4 Here, we present the design of the PROPEL-36 study (NCT04969861) that evaluates BEMPEG + PEMBRO vs PEMBRO alone in patients with previously untreated metastatic or recurrent programmed death ligand-1 (PD-L1)-positive HNSCC (combined positive score ≥1). This phase 2/3, multicenter study is enrolling ≈500 patients with cancer of the oropharynx, oral cavity, hypopharynx, or larynx (excluding nasopharyngeal tumors) and an Eastern Cooperative Oncology Group performance status of 0 or 1. Randomization will be stratified by disease status, PD-L1 expression, and human papillomavirus status. Patients are treated with BEMPEG and/or PEMBRO every 3 weeks for up to 35 cycles (≈2 years). The primary endpoints are OS and objective response rate. Secondary endpoints include progression-free survival, time to deterioration in global health status/quality of life, pain, and swallowing, change in quality of life, and safety. This study is now enrolling. TBD TBD [ABSTRACT FROM AUTHOR]

Modulation of semiconductor–halfmetal–metal transition in the antiferromagnetic (AF) ordering of bilayer zigzag graphene nanoribbons (BZGNRs) on hexagonal boron nitride (h-BN) heterostructure using the external force field F ext and transverse electric fields E ext (in the presence of interaction with the substrate) was performed within the framework of the density functional theory (DFT). We established critical values of E ext and interlayer distance in the bilayer providing for semiconductor–halfmetal–metal transition in one of electron spin configurations. Our calculations also show that the energy gap E g in the AF-BZGNR/h-BN(0001) heterostructure can be controlled in a wide range of the F ext and E ext . This makes the AF-8-ZGNR/h-BN(0001) heterostructure being potentially promising for application in spintronic devices. [ABSTRACT FROM AUTHOR]

Background: The genome of Hepatitis A Virus (HAV) consists of a singlestranded, linear, 7.5 kb RNA molecule encoding a polyprotein that is processed to yield the structural proteins and enzymatic activities required for viral replication. Although HAV is usually acquired by fecal-oral mute, recent reports have raised concerns about the potential for HAV transmission by pooled plasma products. The development of sensitive and specific diagnostic assays to identify HAV viremic samples to exclude them from transfusion and from the preparation of plasma and blood derivatives represents an important challenge for the Blood Industry. HAV expresses three capsid proteins (B, C and D) which contain the major antigenic domains recognized by antibodies of infected individuals. In addition to the capsid proteins, antigenic domains have been reported for the nonstructural protein 2A and for the junction between precursor P1 and 2A. Methods: DNA of the cloned HAV genome was used to amplify, clone and express the capsid proteins B, C and D and the P1-2A viral precursor in Saccharomyces cerevisiae. The initiation ATG codon was incorporated as needed and the HAV nucleotide sequences were cloned in the yeast expression vector pBS24.1. This vector uses the a-factor terminator to ensure transcriptional termination and the yeast gene, leu2-d and ura3, for selection. The vector also contains 2m sequences for autonomous replication in yeast and the b-lactamase gene for selection in bacteria. Yeast pellets containing the HAV recombinant antigens were used for protein purification. Results: The three HAV capsid proteins were cloned and expressed at high levels in Saccharomyces cerevisiae. A recombinant HAV polyprotein consisting of capsid precursor P1 fused with the nonstructural protein 2A was also cloned and expressed in yeast. The immuno-reactivity of each recombinant antigen with a panel of HAV positive samples was evaluated and results showed that P1-2A was the most efficient protein in detecting HAV antibodies in the sera of infected individuals. Conclusion: The availability of the yeast expressed recombinant proteins and the cloned HAV nucleotide sequences will help develop antibody, antigen and nucleic acid tests to identify HAV positive specimens. The resulting assays may have important applications in blood testing and clinical diagnostics. [ABSTRACT FROM AUTHOR]

Reports on developments concerning employees from/in different industries. Background: Parvovirus B19 is a blood borne, single stranded DNA, nonenveloped virus which is not inactivated by the current solvent detergent treatment of plasma. As such, some plasma component manufacturers have adopted Parvovirus B19 DNA testing as an in process quality control test. A Parvovirus B19 nucleic acid detection test set at an appropriate detection level would facilitate removal of donated units with high genomic copy numbers from the blood supply. Methods: A Parvovirus B19 TMA DNA Assay has been developed which involves three major steps: magnetic target capture, amplification by transcription-mediated amplification (TMA), and detection with chemiluminescent probes. The assay is carried out in a single tube using a 500 mL plasma specimen in the standard sample preparation format. The Parvovirus B19 TMA assay was designed to target Parvovirus B19 sensitivity of approximately 500 copies/mL DNA. As a confirmatory method, a Parvovirus B19 quantitative PCR assay using Taqman technology was also developed. Results: To determine assay specificity and prevalence of Parvo B19 DNA in a normal blood donor population, the TMA assay was used to test 468 random blood donor specimens from the Kansas City Community Blood Center. 0.6% (3 of 468) were strongly reactive in the Parvovirus B19 DNA assays. Sensitivity of the TMA assay was estimated based on a Parvovirus B19 DNA specimen obtained from the American Red Cress and quantified by National Genetics Institute. Reactivity of the 500 copy/mL and a 200 copy/mL Parvovirus DNA standard in the assay was 100% (10/10) and 80% (8/10), respectively. The NIBSC Parvovirus B19 standard (99/736) at 1000 gen.eq./mL was also reactive in the assay. Six of 6 Parvovirus specimens reactive by PCR were also reactive in the Parvovirus TMA assay at a 1 to 10 dilution into negative human plasma. None of the six commercially available anti-Parvovirus B19 plasma specimens (obtained from Bioclinical Partners) were reactive in the assay. The Taqman assay showed sensitivity sufficient to confirm TMA reactives. The specificity of the Taqman assay was confirmed by testing 50 random blood donor specimens none of which were positive in the assay. Conclusion: A TMA assay for the detection of Parvovirus B19 DNA showed the sensitivity and specificity required for a blood-screening environment. Confirmation of TMA reactivity by an alternate PCR based NAT will be useful. [ABSTRACT FROM AUTHOR]

Background: Nucleic acid testing (NAT) has been performed on virtually all blood collected in the US since early 1999. Due to the absence of a licensed HCV supplemental NAT assay (SupNAT), an in-house assay was developed with 100 copies/mL (100% detection rate) sensitivity. Methods: The HCV supplemental NAT assay incorporated a guanidinium based lysis of 0.5mL of plasma followed by concentration of RNA using magnetized silica beads. HCV RNA was detected using the Roche COBAS Amplicor HCV version 2.0 reagents. This assay was employed primarily to confirm seronegative (EIA)/NAT positive and seropositive (EIA+)/NAT negative index samples identified in the Chiron Procleixä Clinical Trial as well as F/U samples. Some concordant samples were also tested. Results: From 8/25/00 through 4/30/01, 1,941,285 samples were evaluated using the Chiron Procleixä HIV-1/HCV Assay in both clinical (high prevalence) and donor (low prevalence) settings. The Supplemental NAT laboratory received and tested a total of 523 (0.03%) samples [205(40%) clinical and 318(60%) donor]. SupNAT confirmed Procleixä in 99% of all clinical samples received [12.1% HCV EIA-/SupNAT+ and 87.9% were EIA+/SupNAT+]. In comparison 99% of all samples received from donor sites were confirmed by SupNAT [4% HCV EIA-/SupNAT+ and 96% were EIA+/SupNAT-]. A total of 35 (8 donor and 27 clinical) F/U samples had enough volume for NAT testing. SupNAT results on clinical index samples were confirmed by F/U in 26/27 cases. In all 8 donor cases with F/U samples the index NAT/SupNAT results could not be confirmed by F/U, indicating the initial NAT result was due to tube contamination at the blood center. Conclusions: These data indicate that the Sup NAT assay was appropriate for confirmation of screening NAT assay results. [ABSTRACT FROM AUTHOR]

Background: All blood in the US is currently screened for HIV-1 and HCV RNA. In addition, most plasma houses as well as Germany and Japan have introduced HBV DNA testing of plasma. To meet the needs for nucleic acid amplification testing (NAT) in blood centers, the Transcription-Mediated Amplification (TMA) Triplex Assay has been developed which allows simultaneous detection of HIV-1, HCV, and HBV nucleic acid. Methods: The TMA Triplex Assay involves three major steps: magnetic target capture, amplification by TMA, and detection with chemiluminiscent probes. The assay is carried out in a single tube using a 0.5 mL plasma specimen in the standard sample preparation format. These studies used human plasma sensitivity panels for HIV-1, HCV and HBV, including genetic variants for each virus. For testing of HBV clinical specimens, a panel of samples from chronically infected, HBsAg positive patients and seroconversion panels from BBI and Impath were tested. Negative human plasma was used for specificity studies. Results: Sensitivity of the Triplex Assay was similar to the PROCLEIXäHIV1/HCV Assay for detection of HIV-1 type B and HCV type 1. Sensitivity for detection of HIV-1 and HCV genetic variants was equivalent or better than the PROCLEIX HIV-1/HCV Assay. Specificity for the Triplex Assay was comparable to that seen for the HIV-1/HCV Assay. Using an HBV sensitivity panel calibrated against the WHO International Standard for HBV DNA (97/ 746), we demonstrated approximately 95% detection of HBV DNA at 15 IU/ mL as well as detection of genotypes A, B, C, D, E, F, and G. The Triplex Assay detected 94% (N = 167) of samples from chronically infected, HBsAg positive patients. Five commercially available seroconversion panels were tested and compared to the Abbott PRISM HBsAg assay. The TMA Triplex test detected HBV 8 to 25 days earlier than the antigen test. Conclusion: The sensitivity and specificity results presented here demonstrate the feasibility of amplifying and detecting three unique viral targets (including one DNA and two RNA viruses) in a single TMA assay format without compromising sensitivity for any target. [ABSTRACT FROM AUTHOR]