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This special section is the result of an effort by several scholars to move marketing academic research toward greater practical relevance. This initiative, called Theory + Practice in Marketing (TPM), started with a conference at Columbia Business School in 2011, and the five papers published in this special section were presented at the second TPM conference held at Harvard Business School in 2012. © 2014 INFORMS.

The article discusses issues on commercial general liability (CGL) insurance policies under New York law, particularly with regards to faulty work and the term 'occurrence.' It examines the Tenth Circuit's decision in the case Black & Veatch Corp. v. Aspen Insurance (Great Britain) Ltd., in which faulty subcontractor work could be coverable occurrence under standard CGL policy.

A novel Stenotrophomonas species was isolated as a contaminant in viral transport media at the District of Columbia Department of Forensic Sciences Public Health Laboratory. Phylogenomic and biochemical analyses of the isolate determined that it represented a novel species within Stenotrophomonas . Related strains in public genome databases suggested that this novel species is associated with clinically acquired infections, similar to closely related Stenotrophomonas maltophilia . The name Stenotrophomonas forensis sp. nov. is proposed. Comparative genomic and phylogenetic analyses of the S. maltophilia complex reveal that Stenotrophomonas africana is an independent species and is not a later heterotypic synonym of S. maltophilia . We also propose the transfer of two misclassified Pseudomonas species into Stenotrophomonas as Stenotrophomonas beteli comb. nov. and Stenotrophomonas hibiscicola comb. nov. The type strain for S. forensis sp. nov. is DFS-20110405 T (=ATCC TSD-272 T =NCTC 14893 T ).

Shiga toxin (Stx)-producing Escherichia coli (STEC) is a major cause of foodborne diarrheal illness in the United States and globally, and serotype O157:H7 is frequently associated with STEC outbreaks and sporadic cases in the United States. Severe systemic diseases associated with STEC are mediated by Stx types, particularly subtype Stx2a, encoded on inducible bacteriophages. We previously identified two STEC O157:H7 clinical isolates, JH2010 and JH2012, that exhibit a large difference in virulence in a streptomycin (Str)-treated mouse model. In this study, we aimed to identify a genetic basis for the difference in virulence between those strains. Comparison of the stx 2a phage sequences showed that JH2012 lacks the lytic genes S and R on the phage genome. We also demonstrated that compared to JH2012 cultures, cultures of JH2010 released more Stx2 into the supernatant and were more sensitive to bacterial lysis during growth with ciprofloxacin (Cip), an inducer of stx phages. We therefore generated an stx 2a phage SR deletion mutant strain of JH2010 to determine if those genes were responsible for the high virulence of that strain. We found that deletion of the SR genes from the stx2a phage in JH2010, and another O157:H7 strain, JH2016, resulted in increased cellular retention of Stx2, but there was no difference in virulence compared to the wild-type strains. Our results indicate that the stx 2a phage SR genes are involved in Stx2 localization and phage-mediated cell lysis in vitro but that they are not required in wild-type STEC strains for virulence in a mouse model. IMPORTANCE The release of Stx from STEC has been thought to be tied to phage-mediated lysis of the host bacterial cell. In this study, we found that the stx 2a phage lytic genes are not required for the virulence of pathogenic O157:H7 clinical isolates in a murine model of STEC infection or for release of Stx2a into the supernatant of bacterial cultures. These results point to an alternate mechanism for Stx2a release from STEC strains., Competing Interests: The authors declare no conflict of interest.

Matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS) is widely used for the analysis of biomolecules. Label-assisted laser desorption/ionisation mass spectrometry (LALDI-MS) is a matrix-free variant of MALDI-MS, in which only analytes covalently attached to a laser desorption/ionisation (LDI) enhancer are detected. LALDI-MS has shown promise in overcoming the limitations of MALDI-MS in terms of sample preparation and MS analysis. In this work, we have developed a series of pyrene-based LDI reagents (LALDI tags) that can be used for labelling and LALDI-MS analysis of reducing carbohydrates from complex (biological) samples without the need for additional chemical derivatisation or purification. We have systematically explored the suitability of four pyrene-based LDI enhancers and three aldehyde-reactive handles, optimised sample preparation, and demonstrated the use of LALDI tags for the detection of lactose. We have also exemplified the potential of LALDI tags for labelling carbohydrates in biological samples by direct detection of lactose in cow's milk. These results demonstrate that LALDI-MS is a promising technique for the analysis of reducing carbohydrates in biological samples, and pave the way for the development of LALDI-MS for glycomics and diagnostics., (© 2020 Wiley-VCH GmbH.)

Background: Vitros ECiQ and Architect i2000 SR are two automated instruments used to detect serology biomarkers of hepatitis A, B and C viruses, and HIV infections. We compared performance of the Architect to the Vitro EciQ after implementation at our institution., Methods: A retrospective review was performed to compare patient samples tested on the Vitros ECiQ or Architect for hepatitis and HIV serological assays. The positivity rate, frequency of equivocal results, turnaround times (TAT), and hands-on time (HOT) were analyzed., Results: There was no statistical difference in the positivity rate between the two instruments, with the exception of two assays. An increase in equivocal results was observed for the Architect (0.2% vs 0.5%). Notably, the TAT for the Architect i2000 was shorter for all except one assay (31.6 vs 33.7 hours) and demonstrated improved workflow., Conclusions: Overall, both instruments performed comparably. Architect had shorter TAT over Vitros., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In this study we compared nine Shiga toxin (Stx)-producing Escherichia coli O157:H7 patient isolates for Stx levels, stx -phage insertion site(s), and pathogenicity in a streptomycin (Str)-treated mouse model. The strains encoded stx 2a , stx 1a and stx 2a , or stx 2a and stx 2c . All of the strains elaborated 10 5 -10 6 cytotoxic doses 50% (CD 50 ) into the supernatant after growth in vitro as measured on Vero cells, and showed variable levels of increased toxin production after growth with sub-inhibitory levels of ciprofloxacin (Cip). The stx 2a + stx 2c + isolates were 90-100% lethal for Str-treated BALB/c mice, though one isolate, JH2013, had a delayed time-to-death. The stx 2a + isolate was avirulent. Both an stx 2a and a recA deletion mutant of one of the stx 2a + stx 2c + strains, JH2010, exhibited at least a three-log decrease in cytotoxicity in vitro and both were avirulent in the mice. Stool from Str-treated mice infected with the highly virulent isolates were 10- to 100-fold more cytotoxic than feces from mice infected with the clinical isolate, JH2012, that made only Stx2a. Taken together these findings demonstrate that the stx 2a -phage from JH2010 induces to higher levels in vivo than does the phage from JH2012. The stx 1a + stx 2a + clinical isolates were avirulent and neutralization of Stx1 in stool from mice infected with those strains indicated that the toxin produced in vivo was primarily Stx1a. Treatment of mice infected with Stx1a+Stx2a+ isolates with Cip resulted in an increase in Stx2a production in vivo and lethality in the mice. Our data suggest that high levels of Stx2a in stool are predictive of virulence in mice., (Copyright © 2020 Hauser, Atitkar, Petro, Lindsey, Strockbine, O'Brien and Melton-Celsa.)

Chimeric antigen receptor (CAR) T cell immunotherapy has been a major advancement in cancer therapeutics. Reprogramming of T cells is achieved by using gammaretroviral or lentiviral vectors, which may interfere with human immunodeficiency virus type 1 (HIV-1) nucleic acid amplification testing (NAAT). Here, we describe three clinical scenarios in which CAR T cell immunotherapy interfered with HIV-1 testing, including (i) routine infectious disease screening prior to stem cell transplantation in a 16-year-old female with B cell acute lymphoblastic leukemia, post CAR T cell treatment; (ii) routine infectious disease screening prior to second CAR T cell collection in a 65-year-old male with diffuse large B cell lymphoma who failed initial CAR T cell treatment; and (iii) routine infectious risk assessment following an occupational health exposure from a 58-year-old male with multiple myeloma, who received CAR T cell treatment. In each case, patients initially tested negative by the "fourth-generation" HIV-1 screening enzyme immunoassay (targeting the p24 antigen and anti-HIV-1 antibodies), but positive by the Roche Cobas AmpliPrep/Cobas TaqMan HIV-1 test v2.0 (targeting gag and the long terminal repeat [LTR]). These samples subsequently retested negative using the Abbott m2000 RealTime HIV-1 assay, which targets the integrase gene. These results indicated that cross-reactions between lentiviral vectors and LTR genomes targeted in the HIV-1 NAAT caused the HIV-1 NAAT false-positive results., (Copyright © 2019 American Society for Microbiology.)

Ligand-directed protein labelling allows the introduction of diverse chemical functionalities onto proteins without the need for genetically encoded tags. Here we report a method for the rapid labelling of a protein using a ruthenium-bipyridyl (Ru(II)(bpy) 3 )-modified peptide designed to mimic an interacting BH3 ligand within a BCL-2 family protein-protein interactions. Using sub-stoichiometric quantities of (Ru(II)(bpy) 3 )-modified NOXA-B and irradiation with visible light for 1 min, the anti-apoptotic protein MCL-1 can be photolabelled with a variety of functional tags. In contrast with previous reports on Ru(II)(bpy) 3 -mediated photolabelling, tandem mass spectrometry experiments reveal that the labelling site is a cysteine residue of MCL-1. MCL-1 can be labelled selectively in mixtures with other proteins, including the structurally related BCL-2 member, BCL-x L . These results demonstrate that proximity-induced photolabelling is applicable to interfaces that mediate protein-protein interactions, and pave the way towards future use of ligand-directed proximity labelling for dynamic analysis of the interactome of BCL-2 family proteins., Competing Interests: Competing interests The authors declare no competing interests.

Scholarship on child health indicates that the early years of life are vital for all aspects of health and development. In particular, a solid health foundation predicts good life outcomes; therefore, systematic strategies for combating diseases are needed to ensure optimal health of young children in early care environments. This study examined strategies used by 48 preschool teachers from 10 pre-schools in the US Midwest in order to combat diseases. The following results emerged: Participants noted that children should not attend childcare if they are vomiting, have a fever or have diarrhea. They should be symptom-free for at least one day before returning to school. It is recommended that children be sent home if they have any disease deemed to have adverse effects on their health during the school day. Participants noted further that children must not share hats in their childcare environments to avoid transfer of head lice. Since no strategies were mentioned to help children cope with emotional distress and illness, it is recommended that teachers develop strategies that will address emotional childhood diseases in order to help all children.

2-Cyanobenzothiazoles (CBTs) are useful building blocks for: 1) luciferin derivatives for bioluminescent imaging; and 2) handles for bioorthogonal ligations. A particularly versatile CBT is 6-amino-2-cyanobenzothiazole (ACBT), which has an amine handle for straight-forward derivatisation. Here we present an economical and scalable synthesis of ACBT based on a cyanation catalysed by 1,4-diazabicyclo[2.2.2]octane (DABCO), and discuss its advantages for scale-up over previously reported routes.

Streptococcus pneumoniae produces a protective capsular polysaccharide whose production must be modulated for bacterial survival within various host niches. Capsule production is affected in part by a phosphoregulatory system comprised of CpsB, CpsC, and CpsD. Here, we found that growth of serotype 2 strain D39 under conditions of increased oxygen availability resulted in decreased capsule levels concurrent with an ∼5-fold increase in Cps2B-mediated phosphatase activity. The change in Cps2B phosphatase activity did not result from alterations in the levels of either the cps2B transcript or the Cps2B protein. Recombinant Cps2B expressed in Escherichia coli similarly exhibited increased phosphatase activity under conditions of high-oxygen growth. S. pneumoniae D39 derivatives with defined deletion or point mutations in cps2B demonstrated reduced phosphatase activity with corresponding increases in levels of Cps2D tyrosine phosphorylation. There was, however, no correlation between these phenotypes and the level of capsule production. During growth under reduced-oxygen conditions, the Cps2B protein was essential for parental levels of capsule, but phosphatase activity alone could be eliminated without an effect on capsule. Under increased-oxygen conditions, deletion of cps2B did not affect capsule levels. These results indicate that neither Cps2B phosphatase activity nor Cps2D phosphorylation levels per se are determinants of capsule levels, whereas the Cps2B protein is important for capsule production during growth under conditions of reduced but not enhanced oxygen availability. Roles for factors outside the capsule locus, possible interactions between capsule regulatory proteins, and links to other cellular processes are also suggested by the results described in this study.

The capsular polysaccharide (CPS) is essential for Streptococcus pneumoniae virulence. Its synthesis requires multiple enzymes, and defects that block completion of the pathway can be lethal in the absence of secondary suppressor mutations. In this study, we examined the functions of three capsular glycosyltransferases (Cps2F, Cps2G, and Cps2I) involved in serotype 2 CPS synthesis, whose deletions select for secondary mutations. We demonstrate that Cps2F is a rhamnosyltransferase that catalyzes addition of the third and fourth sugars in the capsule repeat unit, while Cps2G adds the fifth sugar (glucose). Addition of the terminal residue (glucuronic acid) could not be detected; however, activities of the other glycosyltransferases together with bioinformatic analyses suggest that this step is mediated by Cps2I. Most of the secondary suppressor mutations resulting from loss of these enzymes occur in cps2E, the gene encoding the initiating glycosyltransferase. Examination of the 69 S. pneumoniae serotypes containing Cps2E homologues yielded a consensus amino acid sequence for this protein and demonstrated that there is a highly significant association between the residues that are 100% conserved and those altered by suppressor mutations. Cps2E contains an extracytoplasmic loop whose function is unknown. Among our collection of mutants, six contained missense mutations affecting amino acids in the extracytoplasmic loop. These residues are highly conserved among S. pneumoniae Cps2E homologues, and mutations therein severely reduced CPS synthesis and Cps2E activity. The critical functions of these amino acids suggest a role for the Cps2E extracytoplasmic loop in initiation, and possibly regulation, of capsule synthesis.

Three measures of workload were tested during 11 routine missions conducted by the NASA Kuiper Airborne Observatory: communications performance, subjective ratings, and heart rate. The activities that contributed to crewmember workload varied; the commander was responsible for aircraft control and navigation whereas the copilot handled communications with ATC and the astronomers. Ratings of workload, stress, and effort given by the two crewmembers were highly correlated and varied across flight segments, peaking during takeoff and landing. Since the pilots performed different tasks during each segment, their ratings appeared to reflect overall crew workload, rather than experiences specific to each pilot. Subjective fatigue increased significantly from takeoff to landing for all flights, although the increase was significantly greater as landing times shifted from 10:00 p.m. to 9:00 a.m. The type, source, number, and frequency of communications varied significantly across flight segments, providing an objective indicator of pilot workload. Heart rate was significantly higher for the aircraft commander than for the copilot. Although heart rate peaked for both positions during takeoff and landing, the amount of change was significantly greater for the aircraft commander. Subjective ratings of stress, workload, and mental effort were significantly correlated with heart rate and communications frequency but were unrelated to mission duration, rated fatigue, or pilot evaluation of performance.

Treatment of intact toxoplasma tachyzoites with individual mouse monoclonal antibodies to toxoplasma which are directed against individual membrane-associated antigenic determinants facilitated the phagocytosis of toxoplasma and also prepared the toxoplasma for intracellular destruction by nonelicited mouse peritoneal macrophages. In instances in which the organisms survived intracellularly, their multiplication was significantly reduced. Such monoclonal antibodies should be useful in further elucidating the role of antibody in resistance to toxoplasma and other facultative and obligate intracellular organisms.

Incubation of murine peritoneal and spleen natural killer cells with amphotericin B at concentrations of 2.5, 5 and 10 mg/l in vitro, resulted in depression of their tumoricidal activity which had been augmented in vivo by infection with Toxoplasma gondii. In contrast, amphotericin B at the same concentrations had little or no effect on spontaneous natural killer cell activity in vitro. These in-vitro data suggest amphotericin B may have adverse effects on natural killer cell function in vivo.

The ability of sonicates of Toxoplasma gondii and of subcellular fractions of the organism to enhance natural killer (NK) cell activity in mice was examined. Treatment of BALB/c mice with the sonicate preparations enhanced peritoneal and splenic NK activity to the level obtained with intact tachyzoites. Similar augmentation of NK activity in A/J, C57BL/6, and C3H/HeJ mice was also observed. Administration of Toxoplasma sonicate intraperitoneally, intravenously, or subcutaneously enhanced both peritoneal and splenic NK activity. Treatment of mice with a sonicate of L929 fibroblast failed to enhance their NK activity. Concentrations of sonicates ranging from 400 to 4 micrograms of protein enhanced both peritoneal and splenic NK activity. Both the soluble and particulate fractions of the sonicate obtained by differential centrifugation were capable of enhancing peritoneal NK activity, whereas splenic NK activity was enhanced only by the particulate fraction. Heat, protease, and sodium periodate treatment of the Toxoplasma sonicate completely abolished its capacity to augment NK activity. Gel filtration studies revealed that the NK augmenting activity of the Toxoplasma sonicate is distributed over a wide molecular weight range.

Murine spleen natural killer (NK) cells from normal and Toxoplasma-infected BALB/c mice were examined for their reactivity against RH strain tachyzoites in vitro. First, the effect of suspending medium on survival of extracellular RH tachyzoites was determined. Optimal parasite viability (by ethidium bromide-acridine orange staining) was observed when tachyzoites were incubated in phosphate-buffered saline (PBS) containing 10% horse serum (HS) for as long as 5 hr. In addition, parasite viability in PBS-HS correlated with subsequent infectivity, because freshly harvested and PBS-HS-incubated tachyzoites were equivalent in their ability to cause lethal infections in normal mice and to survive within normal mouse macrophages. Furthermore, viability and tumoricidal capacity of murine spleen NK cells incubated in PBS-HS was comparable to that of NK cells incubated in a standard cytotoxicity medium. Incubation of effector NK cells and target tachyzoites in PBS-HS in vitro revealed that spleen NK cells from 3-day Toxoplasma-infected mice had significantly greater cytotoxicity for extracellular RH tachyzoites than did control cells from uninfected mice. Moreover, Toxoplasma gondii-induced spleen NK cell toxoplasmacidal activity was significant at all effector to target cell ratios tested, and appeared to be mediated by direct contact between the host cell and the parasite. These in vitro results suggest that NK cells may be important in host defense against T. gondii.

We describe here a new tissue culture method for prolonged laboratory maintenance of tachyzoites of the highly virulent RH strain of Toxoplasma gondii. Using a rapidly proliferating murine tumor cell line (YAC-1), the method described is easy to perform and is as or more efficient (both in terms of yield and cost) than other traditional methods for maintenance of the parasite. Furthermore, upon prolonged maintenance (greater than 160 days) in YAC-1 tissue culture, the pathogenicity of the parasite, as well as its capacity to elicit an immune response, are comparable to that of organisms maintained in mice. We conclude therefore, that the method described herein is a suitable alternative to the traditional method of maintenance of virulent RH strain T. gondii tachyzoites.

Ion implanted p-n junction photodiodes in epitaxially grown (Ga(x) In(1-x))As material are reported on here. Photoresponse in these diodes was investigated for approximately the entire composition range of 0 < x < 1. High values for quantum efficiency were obtained for the devices with a high value of x. Peak D(*)(lambda,f) of greater than 10(11) [cm(Hz)(1/2)/W] at room temperature was obtained at 0.8-microm wavelength, while a peak D(*)(lambda,f) of 5 x 10(10) [cm(Hz)(1/2)/W] was obtained at 165 K at 1.4-microm wavelength.