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Experimental research has shown the extraordinary potential of the addition of short fibers to cement‐based materials by improving significantly the behavior of concrete structures for serviceability and ultimate limit states. Software based on the finite element method has been used for the simulation of the material nonlinear behavior of fiber‐reinforced concrete (FRC) structures. The applicability of the existing approaches has often been assessed by simulating experimental tests with structural elements, in general of a small scale, where the parameter values of the material constitutive laws are adjusted for the aimed predicting level, which constitutes an inverse technique of arguable utility for structural design practice. For assessing the predictive performance of these approaches, a blind simulation competition was organized. Two twin T‐cross section steel FRC beams, flexurally reinforced with steel bars and without conventional shear reinforcement in the critical shear span, were experimentally tested up to failure. Despite the experimental data provided for the definition of the relevant model parameters, inaccuracies on the load capacity, deflection, and strain at peak load attained 40, 113, and 600%, respectively. Inadequate failure modes and highly different results were estimated with the same commercial software, indicating the need for deeper analysis and understanding of the models and influence of their parameters on their predictive performance. [ABSTRACT FROM AUTHOR]

This paper describes the 3rd Blind Simulation Competition (BSC) organized by the fib WP 2.4.1 which aims to assess the predictive performance of models based on the finite element method (FEM) for analysis and design of fiber reinforced concrete (FRC) structures submitted to loading and support conditions that promote punching failure mode. Fiber reinforcement is used in an attempt to eliminate conventional punching reinforcement and provide technical and economic advantages. The two tested real‐size prototypes represent a column‐slab interior region of an elevated steel‐fiber reinforced concrete (E‐SFRC) slab where anti‐progressive collapse reinforcement is disposed in the alignment of columns/piles. Despite a punching failure surface being formed in both experimentally tested prototypes at the rupture stage, fiber reinforcement was able to mobilize the yield capacity of the conventional flexural reinforcement, providing high deformation capacity, and ductility to the prototypes. The average post‐peak load‐carrying capacity of the tested prototypes at a deflection seven times higher than the deflection at yield initiation of the conventional reinforcement was still 90% of the average peak load. Regarding the BSC, a total of 26 proposals were received and involved 94 participants from 29 institutions and 17 countries, with 53.9% using smeared crack models (SCMs), 30.8% a concrete damage plasticity (CDP) model, 3.8% discrete crack models (DCMs) and 11.5% considered as “other models.” From these simulations it was verified, in average terms, that SCM assured the best predictive performance apart from the average strain in the SFRC and the maximum crack width which were better predicted by DCM. More accurate predictions were obtained by using in‐house software than by adopting commercial software. [ABSTRACT FROM AUTHOR]

THIOMAB antibody technology utilizes cysteine residues engineered onto an antibody to allow for site-specific conjugation. The technology has enabled the exploration of different attachment sites on the antibody in combination with small molecules, peptides, or proteins to yield antibody conjugates with unique properties. As reported previously ( Shen , B. Q. , et al. ( 2012 ) Nat. Biotechnol. 30 , 184 - 189 ; Pillow , T. H. , et al. ( 2017 ) Chem. Sci. 8 , 366 - 370 ), the specific location of the site of conjugation on an antibody can impact the stability of the linkage to the engineered cysteine for both thio-succinimide and disulfide bonds. High stability of the linkage is usually desired to maximize the delivery of the cargo to the intended target. In the current study, cysteines were individually substituted into every position of the anti-HER2 antibody (trastuzumab), and the stabilities of drug conjugations at those sites were evaluated. We screened a total of 648 THIOMAB antibody-drug conjugates, each generated from a trastuzamab prepared by sequentially mutating non-cysteine amino acids in the light and heavy chains to cysteine. Each THIOMAB antibody variant was conjugated to either maleimidocaproyl-valine-citrulline-p-aminobenzyloxycarbonyl-monomethyl auristatin E (MC-vc-PAB-MMAE) or pyridyl disulfide monomethyl auristatin E (PDS-MMAE) using a high-throughput, on-bead conjugation and purification method. Greater than 50% of the THIOMAB antibody variants were successfully conjugated to both MMAE derivatives with a drug to antibody ratio (DAR) of >0.5 and <50% aggregation. The relative in vitro plasma stabilities for approximately 750 conjugates were assessed using enzyme-linked immunosorbent assays, and stable sites were confirmed with affinity-capture LC/MS-based detection methods. Highly stable conjugation sites for the two types of MMAE derivatives were identified on both the heavy and light chains. Although the stabilities of maleimide conjugates were shown to be greater than those of the disulfide conjugates, many sites were identified that were stable for both. Furthermore, in vitro stabilities of selected stable sites translated across different cytotoxic payloads and different target antibodies as well as to in vivo stability.

High throughput protein production from transient transfection of mammalian cells is used in multiple facets of research and development studies. Commonly used formats for these high number expressions are 12-, 24- and 96-well plates at various volumes. However there are no published examples of a 96-deep well plate microscale (1,000 μL) suspension process for mammalian transient expression. For this reason, we aimed to determine the optimal operating conditions for a high producing, microscale HEK293 transient system. We evaluated the hydrodynamic flow and measured the oxygen transfer rate (OTR) and transient protein expression for 96-deep well plates of different well geometries filled at 600-1,000 μL working volumes and agitated at various speeds and orbital diameters. Ultimately, a round well-round bottom (RR) 96-deep well plate with a working volume of 1,000 µL agitated at 1,000 RPM and a 3 mm orbital diameter yielded the highest and most consistent total transient protein production. As plate cultures are subject to evaporation, water loss from different plate seals was measured to identify an optimal plate sealing method. Finally, to enable higher capacity protein production, both expression and purification processes were automated. Functionality of this end-to-end automation workflow was demonstrated with the generation of high levels of human IgG1 antibodies (≥360 µg/mL) with reproducible productivity, product quality and ≥78% purification recovery., (© 2015 Wiley Periodicals, Inc.)

Transient transfection of mammalian cells provides a rapid method of producing protein for research purposes. Combining the transient transfection protein expression system with new automation technologies developed for the biotechnology industry would enable a high throughput protein production platform that could be utilized to generate a variety of different proteins in a short amount of time. These proteins could be used for an assortment of studies including proof of concept, antibody development, and biological structure and function. Here we describe such a platform: a semi-automated process for PEI-mediated transient protein production in tubespins at a throughput of 96 transfections at a time using a Biomek FX(P) liquid handling system. In one batch, 96 different proteins can be produced in milligram amounts by PEI transfection of HEK293 cells cultured in 50 mL tubespins. Methods were developed for the liquid handling system to automate the different processes associated with transient transfections such as initial cell seeding, DNA:PEI complex activation and DNA:PEI complex addition to the cells. Increasing DNA:PEI complex incubation time resulted in lower protein expression. To minimize protein production variability, the methods were further optimized to achieve consistent cell seeding, control the DNA:PEI incubation time and prevent cross-contamination among different tubespins. This semi-automated transfection process was applied to express 520 variants of a human IgG1 (hu IgG1) antibody., (Published by Elsevier B.V.)

Although mass screening for cervical cancer has been operational for more than 2 decades in the Netherlands, 700 women are still diagnosed with this cancer each year (9 per 100,000). We investigated these cases, in order to evaluate opportunities to further increase the effectiveness of the programme. We analyzed the screening history of women diagnosed with cervical cancer between 1994-1997 using the Dutch national pathology file that includes cervical cytology and histological results. More than half of the cases did not have previous preventive cervical smears, and another 30% had never been invited to the programme because of their age. In the future, we estimate that two thirds of all Dutch women with invasive cervical cancer will be unscreened or under-screened, based on current screening participation of more than 70%. We conclude that increasing screening participation has much more potential for further reducing cervical cancer incidence than reducing the screening interval, increasing the age range or having a screening test with higher sensitivity.

Objective: To determine whether the 1996 implementation of new guidelines for the classification and management of cervical smears in the Dutch population screening programme for cervical cancer (i.e. inflammatory symptoms are no longer classified as moderate dysplasia and women with two smears with moderate dysplasia are referred directly to the gynaecologist) was followed by a reduction in both the number of women with repeat smears and the length of follow-up., Methods: The results of all smears of women aged 35-54 years from 1990 onwards, were retrieved from the Dutch Network and National Database for Pathology (PALGA). The percentage of smears with moderate dysplasia was analysed with respect to time. The percentage of women with a histological examination during the follow-up phase of the population screening programme (1990 and 1991) was compared with that for the new screening programme (1996)., Results: Following the implementation of the new guidelines, the percentage of smears with moderate dysplasia was reduced from 10% to 2%. The percentage of women with a histological examination during the follow up of two smears with moderate dysplasia remained the same. The new recommendations for additional smears were not followed: for 28% no repeat smear was available after 2.25 years versus 10% in 1992. There were indications that the referral of women with two cases of moderate dysplasia to a gynaecologist was not strictly adhered to either. Since the introduction of the new guidelines, the estimated percentage of women that should be referred to the gynaecologist following smears with moderate dysplasia has not changed., Conclusion: The new recommendations have lead to fewer smears being classified as moderate dysplasia. The long-term effects, such as a reduction in the length of the follow-up period, can only be analysed in a few years time.

Up to 1995, programme screening for cervical cancer in The Netherlands was targeted at women between 35 and 54 years of age at 3-yearly intervals. Spontaneous screening in addition to programme screening was common practice. Our aim was to compare the underlying risk for cervical neoplasia for women involved in both types of screening. From the national pathological database, we retrieved all primary smears (n=693318) taken in 1994 in The Netherlands. Among the smears registered for screening purposes (39%), 79% was taken within the mass screening programme and 21% was taken for spontaneous screening. The underlying risk was studied from the detection rates of histologically confirmed severe dysplasia or worse, using a multivariate loglinear model, including age and screening history. The detection rate of at least severe dysplasia, adjusted for age and screening history, was equal for women who had a spontaneous smear and for those who had a programme smear (odds ratio (OR): 0.97; 95% Confidence Interval (CI): 0.84-1.14). In our data, women participating in spontaneous screening were not at a higher risk for cervical cancer than women who used programme screening. Therefore, all asymptomatic women in the Netherlands should follow the general guidelines for age-range and screening-interval.

The clinical relevance of the lack of endocervical cells was never well established in a longitudinal study with histologically proven cervical cancer as an end point. From the Dutch Network and National Database for Pathology, results for all negative smears obtained in 1990 and 1991 in the Netherlands were retrieved, as were data for all cytologic and histologic examinations performed after the negative smears before April 1998. There were no significant differences between the proportion of preinvasive lesions (cervical intraepithelial neoplasia 1, 2, and 3) detected after negative smears without endocervical cells compared with negative smears with endocervical cells. The proportion of women in whom invasive cancer developed was the same in both groups. These data suggest there is no reason to advise women with negative smears without endocervical cells to undergo an additional smear.

Objectives: To assess computer-assisted (neural network based) cervical smear screening as a primary tool for the early detection of cervical dysplasia., Design: Longitudinal cohort study., Setting: Cytology laboratory reviewing cervical smears taken by general practitioners in a mass screening program in the Netherlands., Subjects: 846 women who developed (pre-)neoplasia of the cervix in the seven years after the baseline smear, and 5217 controls., Interventions: Cervical smears were evaluated both by conventional light microscopy and with use of the PAPNET Testing System by the same cytotechnologists., Main Outcome Measures: Seven year histological and cytological follow-up results were obtained for all women from a nation-wide pathology database., Results: Conventional screening diagnosed dysplasia or carcinoma in the baseline smears of 458 (54.1%) of the 846 women who were diagnosed with (pre-)neoplasia during follow-up, whereas computer-assisted PAPNET analysis detected such lesions in 462 (54.6%) of these women. In the control population of 5217 (86.0%) women, in whom follow-up revealed no cervical dysplasia, conventional screening gave false positive results in 210 (4.0%) and computer-assisted PAPNET analysis gave false positive results in 207 (4.0%) smears. The areas under the receiver operation curves (AUC) were 80% (95% confidence interval, 78 to 82%) and 79% (95% confidence interval, 77 to 81%) for conventional and PAPNET-assisted screening, respectively., Conclusions: The PAPNET Testing System has similar diagnostic value as the conventional screening of Pap smears when used for primary screening.

Background: To assess the interobserver and intraobserver variation of Papanicolaou (Pap) smear screening with the computer-assisted (neural network based) PAPNET Testing System in diagnosing cervical smear abnormalities, results of agreement were compared with the interobserver and intraobserver variation of conventional smear analysis., Methods: Cervical smears obtained from women in 1996 were reevaluated both by conventional light microscopy and with use of the PAPNET Testing System by the same four investigators, and results were compared with the original screening diagnoses obtained by both methods., Results: The interobserver results for epithelial abnormalities (the degree of agreement between the cytologists), characterized by weighted kappa statistics, were 0.71 (95% CI: 0. 68-0.73) for PAPNET screening and 0.69 (95% CI: 0.66-0.72) for conventional screening. No significant differences were found among the individual results obtained by the four cytotechnologists (intraobserver variation) with conventional screening versus PAPNET reviewing., Conclusions: Pap smear grading with the PAPNET Testing System has interobserver and intraobserver variation similar to that of conventional screening of Pap smears in routine use. Cancer (Cancer Cytopathol), (Copyright 1999 American Cancer Society.)

In The Netherlands, early detection of cervical cancer by programme and spontaneous screening has been common practice for more than two decades. Both types of screening are mainly performed by general practitioners. Therefore, the question is raised of whether programme screening still enhances screening uptake. To answer this question, we analysed the national health interview survey in the years 1992-1996. The coverage rate, defined as the percentage of women with at least one smear taken in the previous 5 years, was 91% for women invited for programme screening compared with 68% for women not invited. The performance of the organised programme in reducing excessive screening, i.e. smears taken in excess of the recommended age and interval range, was not clear and the effect seemed small. Furthermore, we found that half the non-attenders were 'protected' by a recent smear or a hysterectomy, and of the unprotected women, 72% showed a positive attitude towards the programme. We conclude that even after a long history of cervical cancer screening, an organised programme is still required to ensure a high coverage.

Background: Salmeterol is a new inhaled selective beta 2-adrenergic receptor agonist with a long duration of action. We studied the duration of the bronchodilation and the protective effect against methacholine-induced airway obstruction of a single dose of salmeterol in a double-blind, randomized, placebo-controlled, crossover design., Methods: Seventeen boys and three girls with mild-to-moderate asthma participated in the study. On two separate days either 50 micrograms salmeterol or placebo was inhaled. FEV1 and PD20 methacholine were determined before and 1, 4, 8, 12, and 24 hours after inhalation., Results: Salmeterol resulted in a significant bronchodilation compared with placebo, up to 12 hours (p = 0.0001). At 24 hours there was a residual effect that approached significance; mean FEV1 being 8.3% +/- 2.4% above baseline (p = 0.06). Significant protection against airway sensitivity to methacholine after salmeterol inhalation was found at all time points (p < 0.005). Twenty-four hours after administration mean PD20 was still 1.22 +/- 0.29 doubling dose above baseline. No important adverse effects were noted., Conclusion: We conclude that a single dose of 50 micrograms salmeterol in children with asthma gives a long-lasting bronchodilation, exceeding 12 hours, which is comparable to the results in adult studies. The duration of the protection against airway sensitivity to methacholine exceeds 24 hours.