even with 40% segregation, phytase production continued to rise

even with 40% segregation, phytase production continued to rise. After two and a half hours’ induction, phytase production rose again to 1000 U/L, while segregation increased to 80%. It was only after this point that phytase activity started to drop [33]. The data presented in Fig. 5 show that after 4 h induction the fraction of plasmid-bearing cells stood at around 45%,

while the yield factor was still rising. However, as shown by other authors [33], if segregation were to rise even higher, the yield factor could start to fall. High levels of a soluble form of ClpP were expressed in all the experiments from the experimental design used. Plasmid segregation was identified in the system throughout the kanamycin concentration range tested. The lowest concentration of IPTG (0.1 mM) tested in this Forskolin study resulted in greater plasmid ABT263 stability. The statistical analyses made of the procedures used to determine plasmid segregation confirmed that they are reproducible. By using experimental design it was possible to conclude that the optimal point of the system was with 0.1 mM IPTG and 0 μg/mL kanamycin, which yielded 247.3 mg/L ClpP; this optimal condition was validated with success. It should therefore be possible to reduce the inducer concentration tenfold and eliminate the antibiotic from the system while still keeping

protein expression at similar levels and reducing overall process costs. It is also important to highlight the importance of the study of plasmid segregation in recombinant systems, since plasmid stability is one of the lynchpins of recombinant protein production. Experimental design proved to be a powerful tool for determining the optimal conditions for expressing recombinant Dichloromethane dehalogenase protein in E. coli using a minimum number of experiments, enabling an assessment to be made of the effect of each of the

variables, their interactions and experimental errors. It is still common practice in molecular biology for each variable to be evaluated separately, which may result in misinterpretations of the data obtained, because it fails to take account of their interactions. Experimental design enables the selection of the best test conditions for detecting the interactions between the variables, which is not possible empirically by adopting the methods usually used in the area that treat variables independently. These techniques have universal application in the production of recombinant proteins. This work received financial support from Bio-Manguinhos and PAPES V (Programa Estratégico de Apoio à Pesquisa em Saúde) from Fundação Oswaldo Cruz (FIOCRUZ). Karen Einsfeldt and João B. Severo Júnior received scholarships from CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior) and CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico), respectively.

75 mg/kg/hr for the duration of the procedure The interventional

75 mg/kg/hr for the duration of the procedure. The interventional strategy, utilization of adjunct pharmacotherapy, such as glycoprotein IIb/IIIa inhibitors,

and device choice were at the operator’s discretion. Dual antiplatelet therapy was recommended for ≥ 12 months for all patients post procedure. Clinical, procedural, and follow-up data learn more were prospectively collected and stored in a central database. A dedicated data coordinating center performed all data management and analyses. Pre-specified clinical and procedural data and in-hospital complications were obtained from hospital charts reviewed by independent research personnel blinded to the study objectives. Primary source documents were obtained for all events and were used to adjudicate STEMI cases by physicians not involved in the procedures, and who were unaware of the study objectives. The time points and time intervals Veliparib supplier pertaining to STEMI management and system performance were adjudicated and verified by physicians not involved in the study. The institutional review boards at MedStar Washington Hospital Center (Washington, DC) and the MedStar Health Research Institute (Washington, DC) approved this study. Statistical analysis was performed using SAS version

9.1 (SAS Institute Inc., Cary, NC). Continuous variables are presented as mean ± standard deviation (SD) if normally distributed, or median ± interquartile range (IQR) if non-normally distributed. Student’s t test and Wilcoxon rank-sum test were used for comparisons of normally and non-normally distributed continuous data, respectively. Categorical variables are expressed as frequencies and percentage, and compared using chi-square test or Fisher’s exact test through as appropriate. A multivariate logistic regression model was used to determine the independent correlates of DTB > 90 minutes, expressed as odds ratio, with 95% confidence interval. Variables were selected on the basis of overall clinical relevance, with particular attention given to clinical and procedural

factors that may delay time to reperfusion. Variables included self-transport (versus EMS), off-hours presentation (versus on hours), age, female gender, body mass index, diabetes, peripheral vascular disease, prior PCI, prior coronary artery bypass grafting, placement of intra-aortic balloon pump, and American College of Cardiology/American Heart Association type C lesion. A p value < 0.05 is considered statistically significant. A total of 309 consecutive STEMI patients who underwent primary PCI were analyzed, of which 226 arrived by self-transport, and 83 were transported by EMS. The baseline and procedural characteristics in both groups were similar. (Table 1 and Table 2). The majority of patients from both groups presented to the ED during off hours. A significantly higher percentage of EMS-transported patients achieved the time goals of DTB < 90 minutes and DTB < 120 minutes compared to self-transported patients. (Fig.

001) (Fig  3) Comparisons of individual components of DTB (media

001) (Fig. 3). Comparisons of individual components of DTB (median, IQR) are shown in Fig. 4. Door-to-ECG and ECG-to-call intervals were significantly shorter in EMS-transported patients, whereas call-to-lab, lab-to-case start, and case start-to-balloon intervals were similar in both groups. The overall ED processing interval (door-to-call) was shorter in EMS-transported patients, but the cath Alpelisib solubility dmso lab processing interval (call-to-balloon) was similar compared to self-transported patients. (Fig. 3) Compared with EMS-transported patients, self-transported patients took longer to arrive at the ED

from symptom onset (symptom-to-door, 2.3 versus 1.2 hours, p < 0.001), and had a significantly delayed symptom-to-balloon time (4.3 versus 2.5 hours, p < 0.001) (Fig. 5). In-hospital clinical outcomes were similar in both groups, although there was a non-statistical reduction of mortality in the EMS-transported group. (Table 3) On multivariate analysis, (Table 4) self-transport compared with EMS-transport correlated significantly with a DTB > 90 minutes (odds ratio 5.30, 95% confidence

interval 2.56–11.00, p < 0.001). (Table 4) Presentation during off hours was also found to correlate independently with DTB > 90 minutes (odds ratio 3.09, 95% confidence interval 1.63–5.87, p = 0.001). We did not find any significant interaction between self-transport and off-hours presentation. None of the other variables included in the multivariate model correlated

with DTB > 90 minutes. With continued emphasis on shortening the symptom-to-treatment time in patients SB203580 research buy presenting with acute myocardial infarction, the present study detects important findings that may impact this mission: 1) compared to self-transport, EMS transport leads to faster in-hospital ED processing time, translating to reduction in DTB time in STEMI patients undergoing primary PCI; 2) EMS-transported patients experienced shorter delays to hospital care from symptom onset; and 3) self-transport and off hours presentation predicts delayed DTB times. The use of EMS has been recommended as a vital component in STEMI care [6]. The findings from our study were consistent with those from the National Chlormezanone Cardiovascular Data Registry [11], demonstrating that EMS transport in STEMI care reduces not only symptom-to-door times, but also DTB times. Our study was distinct in that we were able to collect data dividing DTB times into component times. This enables us to tease out the impact of EMS transport on specific time intervals, and hence evaluate the in-hospital systems processes leading to eventual reperfusion. Moreover, as one of three primary PCI centers within an urbanized area covered by a single EMS provider, it allowed us to evaluate the impact of different transport modes on system processes with greater consistency.

Here, other initiatives, such as www physiotherapyexercises com,

Here, other initiatives, such as www.physiotherapyexercises.com, are useful. This website, which is appraised in detail in this issue of the journal, allows free online access to definitions of a wide array of exercises used in rehabilitation. Each exercise is described using text, diagrams, and photographs, in some cases supplemented

by video. It therefore provides comprehensive definitions of over 900 exercises. Physiotherapists wishing to describe an exercise can refer to the site knowing that the exercise they name will not be misinterpreted. Other see more aspects (such as resistance, repetitions, and any modifications) still need to be defined, but at least the basic description can be unambiguously agreed upon by reference to the site. Other sites do much to standardise even more complex interventions, such as pulmonary rehabilitation on the Australian Lung Foundation’s Pulmonary Rehabilitation Toolkit website. Physiotherapists should consider using and supporting initiatives such as those described above. Increasing standardisation of the terms we use clinically and in research has the potential to improve communication within the profession. “
“Interest in the therapeutic alliance between clinician and patient began in the fields of medical care (Stewart 1995) and psychotherapy (Hovarth and Symonds 1991, Martin et al Dasatinib cost 2000). The therapeutic alliance, also referred to in the literature as the working

alliance, therapeutic bond, or helping alliance, is a general construct that usually includes in its theoretical definition the collaborative nature, the affective bond, and the goal and task agreement between patients

and clinicians (Martin et al 2000). Other constructs, such as trust (Hall et al 2002) Suplatast tosilate and empathy (Mercer et al 2004), may overlap with this definition and are also used to assess the quality of the alliance. More recently, this concept has been considered in the field of physical rehabilitation, including physiotherapy settings (Hall et al 2010). The evidence has shown that a good therapeutic alliance can positively influence treatment outcomes such as improvement in symptoms and health status and satisfaction with care (Hall et al 2010). A good example comes from musculoskeletal rehabilitation. Patients undergoing physiotherapy for chronic low back pain with a strong therapeutic alliance showed an increase as high as four points on a 0–10 scale of global perceived effect compared to those with a weak therapeutic alliance (Ferreira et al 2009). In the field of physiotherapy, the nature of most interventions is usually long-term. Hence, patients’ adherence to longterm treatment regimens is vital to achieve effective clinical practice (WHO 2003). More broadly, it has been recognised that lack of adherence to long-term therapies results in poor clinical outcomes and unnecessarily high costs of health care (WHO 2003).

Our study does not include antigenic and genetic data of circulat

Our study does not include antigenic and genetic data of circulating strains so we cannot comment on suboptimal antigenic match between the 2011–2012 vaccine and circulating strains in Valencia. Further studies should be conducted over several influenza seasons to assess the variability of Bioactive Compound Library order comparative vaccine effectiveness with the degree of antigenic match between vaccine and circulating viruses. We are grateful to Julián Librero for

his comments on the various drafts of the manuscript, Isabel Muñoz and Manuel Escolano for their continuous support to the research team during the conduct of this study, the Microbiological Surveillance Network in the Valencia Autonomous Community (redMIVA) for their assistance and for sharing their data and to all the members of the Valencia Hospital Network for the Study of Influenza and Respiratory Virus Diseases. Conflict of interest: JPB, ANS, SMU and JDD work in FISABIO’s Vaccines Research Area, FISABIO has received funding for GSK, Novartis, Pfizer, SanofiPasteur, SanofiPasteur MSD for conducting epidemiological studies on infectious disease epidemiology, vaccine effectiveness, pharmacoeconomics, and safety studies. The Vaccines Research Area is and has been involved in various randomized clinical trials

with CT99021 research buy GSK, Novartis, Pfizer and MSD vaccines. No conflicts related to

the submitted paper are declared by the rest of the authors. Funding: This work was supported by a grant from the Spanish Ministry of Health to support independent clinical research, Order SPI/2885/2011, October 20, 2011 [grant number EC11-480]. “
“Neonatal vitamin A supplementation (NVAS) is currently under investigation as a public health intervention to combat vitamin A deficiency and mortality in areas afflicted by vitamin A deficiency. We have studied the effect of NVAS on infant mortality in three randomized trials in Guinea-Bissau. One trial randomized normal birth weight neonates (≥2500 g) 1:1 to 50,000 IU vitamin A or placebo (VITA I, 2002–2004) [1]. A second trial randomized low birth weight neonates Parvulin (<2500 g) 1:1 to 25,000 IU vitamin A or placebo (VITA II, 2005–2008) [2]. A third trial randomized normal birth weight neonates 1:1:1 to 50,000 IU vitamin A, 25,000 IU vitamin A or placebo (VITA III, 2004–2007) [3]. We observed that NVAS interacted with subsequent routine vaccinations in a sex-differential manner; the effect of NVAS tended to be negative in females once they started receiving the diphtheria–tetanus–pertussis vaccine (DTP) recommended at 6 weeks of age [2] and [4]. From 2003 to 2007 a trial randomizing children to early measles vaccine (MV) at 4.

meningitidis The DNA content of N meningitidis was somewhat hig

meningitidis. The DNA content of N. meningitidis was somewhat higher at the highest applied growth rate. The phospholipid and lipopolysaccharide

contents in N. meningitidis varied with growth rate but no specific trends were identified. The cellular fatty acid composition and the amino acid buy Staurosporine composition did not vary significantly with growth rate. Additionally, the PorA content in the OMV was significantly lower at the highest growth rate. The metabolic fluxes at different growth rates were calculated using flux balance analysis. Errors in these calculations were detected using Monte Carlo Simulation. Thus the reliability of these calculated values of flux distribution could be specified, which are not reported for this type of analysis. The yield of biomass on the substrate (Y(x/s)) and the maintenance coefficient (m(s)) were determined as 0.44 (±0.04) g/g and 0.04 (±0.02) g/(g h), respectively. The growth associated energy requirement (Y(x/ATP)) selleck chemicals llc and the non-growth associated ATP requirement for maintenance (m(ATP)) were estimated 0.13 (±0.04) mol/mol and 0.43 (±0.14) mol/mol h, respectively. These authors found the split ratio between the Entner–Doudoroff and the pentose phosphate pathways. The pathways utilizing glucose alone in N. meningitidis, had a minor effect on ATP formation rate but a major effect

on the fluxes going through, for instance, the citric-acid cycle. Therefore, they presented flux values in ranges for the underdetermined parts of metabolic network

rather than presenting single values, which is the more common practice in literature. The studies aiming biomass or OMV production reported in previous literature and cited above were performed employing glucose as principal carbon source, instead lactate as in the present study. So no comparisons can be performed between them and the present one. The empirical expression proposed by Luedeking & Piret [35] was used for analysis of the main cultivation product. It relates the specific product formation rate (μP) with the specific growth rate of microorganism (μX) by the equation μP = α·μX + β. Metalloexopeptidase This equation, where α and β are empirical constants, indicates the existence of two mechanisms of production of the product. The first is associated with bacterial growth (represented by α·μX) while the other is independent of the growth of microorganisms (represented by β) [36]. A computer program (Logiciel du Lissage), based on polynomial fit by the Spline method [37] was employed for OMV curve fitting and calculation of specific product formation rate. In the present study, product formation is non-growth associated. The values of β = μP obtained for each assay are presented in Table 1. Series C assays presented the highest values of β, signifying the best cultivation condition among those studied for production of OMV.

5 μl, 1 μl,

2 μl, and 4 μl) DMSO solution of 100 mM NHS-d

5 μl, 1 μl,

2 μl, and 4 μl) DMSO solution of 100 mM NHS-dPEG12-biotin. 100 μl of the suspension was kept for auto fluorescence reference. The cells in each tube were washed with 150 μl of PBS buffer three times, suspended in 20 μl of PBS and supplemented with 15 μl of 5 μM AV – Probe 1-Eu3+. After incubation at room temperature for 20 min, the cells were washed with 100 μl of PBS buffer and suspended in 50 μl of the same buffer. One microliter of Poly-l-lysine was spread onto a fused silica microscope substrate into an area of 0.3 cm2 and removed. One microliter of the cell suspension of labeled cells (E. coli or CHO cells) containing 109–1010 cells cm−3 in PBS buffer was spread into the same area and left to air dry for 15 min. Excitation and emission fluorescence spectra in the continuous excitation mode were recorded using QuantaMaster 1 (Photon Technology International) digital fluorometer at ambient temperature. Time-resolved Dabrafenib price and gated luminescence selleck screening library measurements were performed using the previously described home-built experimental set-up [13]. A Hacker Instruments Zetopan microscope was equipped with an ICCD Camera (PI-MAX, Princeton Instruments). In the experiments, the images were taken in luminescence light using evanescent wave excitation at 351 nm as well as in scattered light using standard top illumination by xenon lamp. In the evanescent excitation, a right angle fused silica prism was illuminated

with laser light (351 nm) from a XeF laser (OPTEX, Lambda Physik). The sample was located on the hypotenuse side of the prism positioned horizontally. Images taken in scattered light from a xenon lamp were taken before and after first the luminescent images collected in the photon counting mode. Online thresholding mode was used to discriminate photon pulses from the readout noise as well as the “cosmic events”. The 1024 × 1024 camera pixels were 8 × 8 binned resulting in 128 × 128 pixel2 images.

The microscope used an objective with the magnification of ×56 and the numerical aperture of 0.90. Combined with the intermediate “ocular” lens with the magnification of ×10 it provided the field of view of 14 × 14 μm2. In some experiments, an ×5 intermediate “ocular” lens was used resulting in the 28 × 28 μm2 field of view. The cells labeled with avidin carrying multiple probes (Probe 1-Eu3+ and Probe 4-Tb3+) were placed on the hypotenuse side of the prism mounted at the microscope base. The excitation of probes occurred in the evanescent wave by laser light totally internally reflected from the hypotenuse side inside the prism. The probes with Eu3+ have emission lifetime of ca. 0.5 ms, while the probes with Tb3+ have emission lifetime of ca. 1.5 ms. Therefore, for samples labeled with Eu3+ probes we used a gate width of 1 ms and the gate delay of 50 μs and for samples labeled with Tb3+ probes 2 ms gate width and 100 μs gate delay were used.

In order to further characterize HPV antibody responses in a 2- v

In order to further characterize HPV antibody responses in a 2- vs. 3-dose randomized controlled Q-HPV vaccine trial, we adapted and implemented the National Institutes of Health pseudovirus neutralizing antibody (PsV NAb) assay [9], in which a red fluorescent

protein (RFP) reporter plasmid was incorporated into the PsV [10]. Neutralizing antibodies block PsV entry into susceptible cells and prevent expression of the RFP which is visualized by fluorescence microscopy. While PsV NAb assays are technically complex and have not been standardized, they provide an alternative to vaccine manufacturers’ assays by detecting type-specific antibodies that block HPV infection of susceptible cells. We previously reported HPV 16 and 18 PsV CHIR-99021 manufacturer NAb and cLIA responses for the 2- vs. 3-dose trial at 7 months post-vaccination [11]. We now report HPV 16 and HPV

18 PsV NAb, Merck cLIA and Merck TIgG antibody responses through to 36 months Ku-0059436 datasheet post-vaccine. The study population consisted of 824 females aged 9–26 years at three study sites in Canada (British Columbia, Québec and Nova Scotia), who were enrolled into one of three study arms as previously described [12]. Younger subjects (9–13 yr) were randomly assigned to receive two or three doses of Q-HPV vaccine, whereas older subjects (16–26 yr) received only the standard three dose regimen. Distribution among the study arms was: Group 1 (n = 259), 9–13 yr (mean age 12.4 yr), received two doses at months 0 and 6; Group 2 (n = 260), too 9–13 yr (mean age 12.3 yr), received three doses at months 0, 2 and 6; and Group 3 (n = 305), 16–26 yr (mean age 19.3 yr), received three doses at months 0, 2 and 6 ( Fig. 1). Sera were collected from the entire cohort at baseline, months 7 and 24; in addition, half the cohort was randomly selected for serum collection at month 18, and the other half had serum collected at month 36. Group 3 subjects also provided self-collected vaginal swabs (HC™ Female Swab Specimen Collection Kit; Qiagen) to determine if HPV 16 or HPV 18 DNA positivity

at baseline impacted the respective antibody responses. Informed consent was obtained for all subjects after explaining the nature and possible consequences of the study. The study was approved by the University of British Columbia Clinical Research Ethics Board and by local research ethics boards at the other sites. The clinical trial was registered with ClinicalTrials.gov (NCT00501137). The PsV NAb assay was performed as previously described [10]. Briefly, HPV 16 and 18 PsV incorporating RFP were prepared by transfection of 293TT cells with HPV 16 or 18 L1 and L2 plasmids together with RFP plasmids. PsV preparations were purified and titrated in 293TT cells. The PsV L1 protein concentrations were estimated by comparing polyacrylamide gel electrophoresis L1 band densities for each PsV preparation with the densities of known concentrations of HPV 16 and 18 Merck vaccine VLPs.

3A) This weakens the effectiveness of the nearby synaptic connec

3A). This weakens the effectiveness of the nearby synaptic connection, and reduces the firing of neurons that generate the mental representations needed for top-down control. In contrast, high levels of catecholamines strengthen the affective responses of the amygdala, the habitual responses of the striatum, and primary sensory cortical function. Cortisol has been shown to accentuate the effects of catecholamines in the PFC and the amygdala (Barsegyan et al., 2010), thus creating a coordinated stress response. The following reviews catecholamine actions in the PFC and amygdala, and the effects of stress on NE and DA neurons. Pyramidal cell circuits in the dlPFC interconnect on dendritic spines through glutamatergic,

NMDA receptor synapses (Fig. 3; Wang et al., 2013). The functional strength of these synapses is dynamically modulated to rapidly enhance or weaken connections, and thus help to shape the contents and strength of working memory. These Cell Cycle inhibitor very rapid changes in synapse

strength, called Dynamic Network Connectivity, are mediated by feedforward, cAMP-Ca2+ signaling events, which open K+ channels near the synapse to weaken the connection (Fig. 3A; Arnsten et al., 2012). Catecholamines can either inhibit or activate these signaling events to strengthen (e.g. when we are safe) or weaken (e.g. when we are stressed) PFC network function. Epigenetic inhibitor nmr This contrasts with cAMP-Ca2+ signaling actions in more primitive circuits, where increases in cAMP-Ca2+ generally strengthen synaptic connections, e.g. via long-term potentiation. These opposing actions in different brain circuits may help begin to explain why dendrites retract in PFC, but hypertrophy in amygdala,

in response to chronic stress. Thus, understanding the cellular effects of the catecholamines may be especially Phosphatidylinositol diacylglycerol-lyase important for treatment strategies. The following provides a brief review of DA and NE actions in the PFC. Initial studies of stress effects on PFC function focused on the role of DA, revealing that increased DA stimulation of D1 receptors in the PFC impaired working memory (Arnsten, 1998 and Murphy et al., 1996). Mild stress preferentially increases DA release in the PFC but not in striatum (Deutch and Roth, 1990), likely involving release from “salience” DA neurons that fire to aversive as well as rewarding events (Matsumoto and Hikosaka, 2009 and Bromberg-Martin et al., 2010). Indeed, even a very mild stress such as receiving water instead of juice increases DA release in the primate dlPFC (Kodama et al., 2014). Studies in rats showed that the levels of DA release in PFC during stress exposure correlated with the degree of working memory impairment (Murphy et al., 1996), and that treatments that blocked DA D1 receptors or reduced DA release protected cognitive performance from the detrimental effects of stress in both rats and monkeys (Arnsten and Goldman-Rakic, 1998 and Murphy et al., 1996).

1), by means of computer generated random numbers, printed and pl

1), by means of computer generated random numbers, printed and placed in opaque envelopes, sealed and numbered. After signing the consent form the envelopes were opened in the order of presentation of the volunteers. Randomization used permutation blocks of size 6, ratio of 1:1. The codes were opened after statistical analysis. Each vial of vaccine was used in only one participant. The MMR vaccine was administered according to routine immunization services, Z-VAD-FMK manufacturer without interference

from the study. The number of participants was calculated using the following parameters: beta = 0.2, alpha = 0.05 (two-tailed test), 90% seroconversion in one group (p1), and minimum difference between the groups (p1 − p2) of 5 percentage points [11]. The sample size with a 20% correction for loss of follow up was 1740 children, 870 in each comparison group. A questionnaire was administered before vaccination with items on age, sex, birth weight and weight at vaccination, immunization history and history

of allergies to food and drugs. We asked the children’s parents to record daily, in a diary, during the 10 days after the vaccination, the adverse events expected for the yellow fever Epacadostat vaccine (fever, vomiting, pain and redness at the injection site and irritability) and any health problems observed in that period. The clinical events occurring after this period were recorded on a postvaccination questionnaire. Samples of 4 mL of blood were collected on the day of MMR vaccination and 30 days after yellow fever vaccination to titrate antibodies against yellow Oxymatrine fever, rubella, measles and mumps. Thus, subgroups

defined by the interval between the vaccines also differed in the interval between post-vaccination blood collection and MMR: 30 days in those who received the vaccines on the same day and 60 days in those who received YFV 30 days after. The titration of antibodies against yellow fever and the antibodies against measles was performed at Virologic Technology Laboratory of Bio-Manguinhos (LATEV, FIOCRUZ, Rio de Janeiro) with Plaque Reduction Neutralization Test (PRNT). PRNT was conducted in serial twofold dilutions starting at 1:5, in 50 μL aliquots of heat inactivated (at 56 °C for 30 min) serum, in 96-well tissue culture plates. A positive monkey serum sample with yellow fever antibody content calibrated by a WHO International Reference Preparation, with 1115 mIU/mL was the standard serum for each set of tests [12]. For measles the standard serum contained 3000 mUI/mL [13]. The log10 dilution of the test sera and the standard serum, which reduced the plaque numbers by 50% relative to the virus control, was determined by linear interpolation. To convert reciprocal dilutions into mIU/mL a unitage constant was calculated for each assay run, dividing the antibody concentration in the standard serum by the reciprocal dilution of the standard serum in that assay run.