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Abstract: This article summarizes the current status of 1H MRS in detecting and quantifying a boron neutron capture therapy (BNCT) boron carrier, l-p-boronophenylalanine-fructose (BPA-F) in vivo in the Finnish BNCT project. The applicability of 1H MRS to detect BPA-F is evaluated and discussed in a typical situation with a blood containing resection cavity within the gross tumour volume (GTV). 1H MRS is not an ideal method to study BPA concentration in GTV with blood in recent resection cavity. For an optimal identification of BPA signals in the in vivo 1H MR spectrum, both pre- and post-infusion 1H MRS should be performed. The post-infusion spectroscopy studies should be scheduled either prior to or, less optimally, immediately after the BNCT. The pre-BNCT MRS is necessary in order to utilise the MRS results in the actual dose planning. [Copyright &y& Elsevier]

The paternally inherited Y chromosome is highly informative of genetic ancestry, therefore making it useful in studies of population history. In Finland, two Y-chromosomal haplogroups reveal the major substructure of the population: N1a1 enriched in the northeast and I1a in the southwest, suggested to reflect eastern and western ancestry contributions to the population. Yet, beyond these major Y-chromosomal lineages, the distribution of finer-scale Y-chromosomal variation has not been assessed in Finland. Here, we provide the most comprehensive Y-chromosomal study among the Finns to date, exploiting sequences for 1802 geographically mapped Finnish Y chromosomes from the FINRISK project. We assessed the distribution of common Y-chromosomal haplogroups (frequency ≥1%) throughout 19 Finnish regions and compared the autosomal genetic backgrounds of the Y-chromosomal haplogroups. With such high-resolution data, we were able to find previously unreported sublineages and resolve phylogenetic relationships within haplogroups N1a1 (64%), I1a (25%), R1a (4.3%), and R1b (4.8%). We further find novel geographical enrichment patterns among these Y-chromosomal haplogroups, most notably observed for haplogroup N1a1 dividing into two lineages with differing distributions. While sublineage N-Z1934 (42%) followed a northeastern enrichment pattern observed for all N1a1 carriers in general, sublineage N-VL29 (22%) displayed an enrichment in the southwest. Further, the carriers of N-VL29 showed a higher proportion of southwestern autosomal ancestry compared to carriers of N-Z1934. Collectively, these results point to distinct demographics within haplogroup N1a1, possibly induced by two distinct arrival routes into Finland. Overall, our study suggests a more complex genetic population history for Finns than previously proposed., (© 2024. The Author(s).)

Objective: This study aimed to determine the survival of class II composite restorations in premolars and molars with and without base bulk-fill composite in general dental practice., Materials and Methods: We collected data from the electronic patient files of the Public Dental Services in the City of Oulu, Finland. The timespan of data collection was from August 15th, 2002, to August 9th, 2018. The data consisted of class II composite restorations both with and without base bulk-fill composite. We compared the survival of these restorations using Kaplan-Meier survival curves, the log-rank test, survival rates, and the Wilcoxon signed ranks test., Results: We observed 297 restorations in 96 patients. The five-year survival rates for restorations with and without base bulk-fill composite were comparable in premolars (77.5% and 77.4%, respectively) but different in molars (69.9% and 57.8%, respectively, p = 0.069). In molars, the restorations with base bulk-fill composite exhibited a higher survival rate in 14 patients, whereas in 11 patients the restorations without base bulk-fill composites exhibited a higher survival rate. In 24 patients the survival rates were similar for restorations with and without the base bulk-fill composite (p = 0.246)., Conclusions: The restorations with and without base bulk-fill composite had similar longevity., Clinical Relevance: Base bulk-fill composites are safe to use in general practice due to their similar survival rates compared to conventional composites., (© 2024. The Author(s).)

Dental caries, gingivitis, and excess weight are highly prevalent, interconnected chronic conditions. The association of oral health with the development of adiposity among children is sparsely addressed. We examined the association of oral health to the development of excess weight and central obesity in early adolescence during a 2-year follow-up period. This prospective study was conducted with 2702 children aged 9-12 years at baseline from the Finnish Health in Teens study. Their weight development was followed up for 2 years. Body mass index with age- and sex-specific cut-offs and the waist-height ratio indicated weight status and central obesity. Oral health data (caries experience and gingivitis/calculus) were collected from outpatient records of public dental services. Having both caries experience and gingivitis/calculus was considered burden of oral diseases. Of the sample, 74% were caries-free but 70% exhibited gingivitis and/or calculus, and 20% had both caries experience and gingivitis/calculus. During the follow-up period, 5.3% (n = 124) and 4.7% (n = 118) of the children became overweight/obese or centrally obese, respectively. Having both caries experience and gingivitis/calculus associated with the development of excess weight in a fully adjusted model (HR 1.75, 95% CI 1.03-2.97) but not of central obesity. Caries experience or gingivitis/calculus alone did not associate with adiposity development., Conclusion: Having burden of oral diseases without excess weight at early adolescence could imply future weight gain; thus, normal-weight individuals with both caries experience and gingivitis/calculus could be targeted with preventive measures. Our findings warrant further research to explore whether oral diseases and the development of obesity merely share risk factors or if their relationship is of causal nature., What Is Known: • Association of excess weight with caries experience and gingivitis is known to exist both cross-sectionally and longitudinally in children and adolescents., What Is New: • Burden of oral diseases, that is, having both caries experience and gingivitis/calculus, was associated with becoming overweight or obese 2 years later during early adolescence. • Normal-weight individuals with burden of oral diseases at early adolescence could be targeted with preventive measures against excess weight gain., (© 2024. The Author(s).)

Background: Pubertal growth patterns correlate with future health outcomes. However, the genetic mechanisms mediating growth trajectories remain largely unknown. Here, we modeled longitudinal height growth with Super-Imposition by Translation And Rotation (SITAR) growth curve analysis on ~ 56,000 trans-ancestry samples with repeated height measurements from age 5 years to adulthood. We performed genetic analysis on six phenotypes representing the magnitude, timing, and intensity of the pubertal growth spurt. To investigate the lifelong impact of genetic variants associated with pubertal growth trajectories, we performed genetic correlation analyses and phenome-wide association studies in the Penn Medicine BioBank and the UK Biobank., Results: Large-scale growth modeling enables an unprecedented view of adolescent growth across contemporary and 20th-century pediatric cohorts. We identify 26 genome-wide significant loci and leverage trans-ancestry data to perform fine-mapping. Our data reveals genetic relationships between pediatric height growth and health across the life course, with different growth trajectories correlated with different outcomes. For instance, a faster tempo of pubertal growth correlates with higher bone mineral density, HOMA-IR, fasting insulin, type 2 diabetes, and lung cancer, whereas being taller at early puberty, taller across puberty, and having quicker pubertal growth were associated with higher risk for atrial fibrillation., Conclusion: We report novel genetic associations with the tempo of pubertal growth and find that genetic determinants of growth are correlated with reproductive, glycemic, respiratory, and cardiac traits in adulthood. These results aid in identifying specific growth trajectories impacting lifelong health and show that there may not be a single "optimal" pubertal growth pattern., (© 2023. The Author(s).)

Objectives: The aims of this randomised controlled laboratory trial were to determine the procedure time and immediate quality (surface porosity and marginal gaps) of fillings placed using the bulk-fill base technique and the conventional incremental technique in simulated clinical settings., Methods: Forty-two dentists and dental students were randomly allocated to use either the bulk-fill base technique or the conventional incremental technique to fill an identical class II disto-occlusal cavity in a maxillary left first molar typodont tooth. We recorded the time the participants used to fill the cavity and evaluated the surface porosity and marginal gaps on the approximal surfaces of the fillings using a stereomicroscope and specific probes according to the FDI criteria for restoration evaluation. Data were analysed using the Mann-Whitney U, Kruskal-Wallis, and chi-square tests., Results: The median time ± interquartile range was 186 ± 80 s for the bulk-fill base technique and 463 ± 156 s for the conventional incremental technique (p < 0.001). The quality of the fillings was better for the bulk-fill base technique than for the conventional incremental technique (X 2  = 9.5, p = 0.002). Neither operator experience nor the usual technique of choice were associated with the procedure time or the quality of the fillings., Conclusions: Compared to the conventional incremental technique, the use of the bulk-fill base technique shortened the time to fill a cavity by 59.8 % or 4 min and 36 s, and it improved the immediate surface and marginal quality of the fillings, regardless of the operator's experience or technique preference., Clinical Significance: The use of the bulk-fill base technique instead of the conventional incremental technique leads to significant time-savings when placing large class II composite fillings. Additionally, the use of the bulk-fill base technique instead of the conventional incremental technique improves the immediate quality of large class II composite fillings., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

We examined cross-sectional and longitudinal associations of dietary factors with caries experience in a population sample of 487 children aged 6-9 years at baseline examinations of the Physical Activity and Nutrition in Children (PANIC) Study. Altogether, 406 of these children attended 2-year follow-up examinations. Food consumption and eating frequency were assessed using 4-day food records, diet quality using the Baltic Sea Diet Score (BSDS) and eating behaviour using the Children's Eating Behavior Questionnaire. Caries experience was examined clinically. The cross-sectional associations of dietary factors with caries experience at baseline were analysed using linear regression and the longitudinal associations of dietary factors with a change in caries experience over follow-up using generalised mixed-effects regression adjusted for other risk factors. A higher consumption of high-fibre grain products (standardised regression coefficient β = -0·16, P = 0·003) and milk ( β = -0·11, P = 0·025) and higher BSDS ( β = -0·15, P = 0·007) were associated with lower caries experience, whereas a higher consumption of potatoes ( β = 0·11, P = 0·048) and emotional overeating ( β = 0·12, P = 0·025) were associated with higher caries experience. Higher snacking frequency (fixed coefficient β = 0·07, P = 0·033), desire to drink ( β = 0·10, P = 0·046), slowness in eating ( β = 0·12, P = 0·027) and food fussiness ( β = 0·12, P = 0·018) were associated with higher caries experience, whereas enjoyment of food ( β = -0·12, P = 0·034) and higher BSDS ( β = -0·02, P = 0·051) were associated with lower caries experience.

This study's aim is to increase insights into the characteristics and conditions of municipal health promotion strategy work. Specifically, we aim to find barriers connected to strategy work, that is, creating and formulating municipal health promotion strategy documents, with the following empirical research question: What perceptions do municipal health promotion strategy actors have on barriers connected to low citizen participation, narrow cross-departmental collaboration and weak goal orientation in health promotion strategy work? Empirical data comprised 22 thematics, individual interviews collected from municipal managers, sector managers and municipal health coordinators. Analysis was conducted using content analysis. This study's findings showed that the main barriers impeding optimal strategy work conditions were administrators' sceptical views of participation and undeveloped administrative practices in inclusive citizen participation, inadequate leadership to unite actors and facilitate collaborative strategy work practices, and challenges in integrating various views into coherent strategic goals. Also, a need for boundary-spanning leadership that strengthens mutual interaction and creates a shared understanding of health promotion to build strategic collaboration and goal-oriented strategy work was revealed. Finally, to strengthen this leadership, influencing administrators' mindsets, behaviour and administrative culture is imperative., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Excess sugar consumption-common in youth-is associated with poor health. Evidence on the relationship between sugar consumption and the oral microbiome, however, remains scarce and inconclusive. We explored whether the diversity, composition, and functional capacities of saliva microbiota differ based on the consumption of select sugary foods and drinks ("sweet treats"). Using 16S rRNA gene sequencing, we characterized saliva microbiota from 11 to 13-year-old children who participated in the Finnish Health in Teens (Fin-HIT) cohort study. The sample comprised children in the lowest ( n = 227) and highest ( n = 226) tertiles of sweet treat consumption. We compared differences in the alpha diversity (Shannon, inverse Simpson, and Chao1 indices), beta diversity (principal coordinates analysis based on Bray-Curtis dissimilarity), and abundance (differentially abundant operational taxonomic units (OTUs) at the genus level) between these low and high consumption groups. We performed PICRUSt2 to predict the metabolic pathways of microbial communities. No differences emerged in the alpha diversity between low and high sweet treat consumption, whereas the beta diversity differed between groups ( p = 0.001). The abundance of several genera such as Streptococcus , Prevotella , Veillonella , and Selenomonas was higher in the high consumption group compared with the low consumption group following false discovery rate correction ( p < 0.05). Children with high sweet treat consumption exhibited higher proportions of nitrate reduction IV and gondoate biosynthesis pathways compared with the low consumption group ( p < 0.05). To conclude, sweet treat consumption shapes saliva microbiota. Children who consume a high level of sweet treats exhibited different compositions and metabolic pathways compared with children who consume low levels of sweet treats. Our findings reveal novel insights into the relationship between sugary diets and oral microbiota., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Lommi, Manzoor, Engberg, Agrawal, Lakka, Leinonen, Kolho and Viljakainen.)

Background: The concept of minimal intervention dentistry (MID) includes both delayed restorative treatment and conservative caries removal, and is now recognised as an evidence-based approach for dental caries management. In order to determine if dental professionals in Russia are incorporating this concept into their clinical practice, we investigated the restorative treatment decisions of Russian dentists and dental students, and the factors associated with these decisions., Methods: We included 171 general dental practitioners and dental therapists (collectively referred to here as "dentists") from North-West Russia, and 76 dental undergraduate students from the Northern State Medical University in Arkhangelsk (response rate of 11.5% and 67.9%, respectively). Participants completed a questionnaire, which collected background information (sex, region of work, place of dental school graduation, practice type, years of working experience, working in an urban or rural area, and specialisation in restorative dentistry) and information on restorative treatment decisions for proximal and occlusal carious lesions of permanent teeth. Treatment options in accordance with MID were defined as intervention at dentin level and minimally invasive cavity preparation. Multinomial logistic regression was used for statistical analysis., Results: For the proximal carious lesion, 9.4% of participants said they would employ both MID treatment options; 60.7% said they would choose only one; and 29.9% said they would use neither option. For the occlusal carious lesion, the corresponding figures were 37.2%, 52.1%, and 10.7%. No differences in restorative treatment options were observed among general dental practitioners, dental therapists, and dental students. For the proximal carious lesion, dentists from regions outside Arkhangelsk had 4.15 (95% confidence interval [CI] 1.13-15.27) times higher odds of following one versus both MID treatment options. For the occlusal carious lesion, working experience above 15 years was associated with higher odds of using only one versus both MID treatment options (adjusted odds ratio = 3.04, 95% CI 1.33-6.91). Almost all respondents preferred tooth-coloured materials for restorations; more than 75% chose resin-based composite., Conclusions: The majority of Russian dentists and dental students do not apply the MID concept when treating dental caries in permanent teeth. Clinical protocols on dental caries treatment and dental school curriculums should be updated to place an enhanced focus on evidence-based practice and preventive strategies. Further studies with larger samples of Russian dentists and dental students and alternative methods of recruitment are needed to validate our results., (© 2021. The Author(s).)

The Global Alliance for Genomics and Health (GA4GH) supports international standards that enable a federated data sharing model for the research community while respecting data security, ethical and regulatory frameworks, and data authorization and access processes for sensitive data. The GA4GH Passport standard (Passport) defines a machine-readable digital identity that conveys roles and data access permissions (called "visas") for individual users. Visas are issued by data stewards, including data access committees (DACs) working with public databases, the entities responsible for the quality, integrity, and access arrangements for the datasets in the management of human biomedical data. Passports streamline management of data access rights across data systems by using visas that present a data user's digital identity and permissions across organizations, tools, environments, and services. We describe real-world implementations of the GA4GH Passport standard in use cases from ELIXIR Europe, National Institutes of Health, and the Autism Sharing Initiative. These implementations demonstrate that the Passport standard has provided transparent mechanisms for establishing permissions and authorizing data access across platforms., Competing Interests: A.A.P. is a venture partner at GV and an employee of Alphabet Corporation and has received funding from MSFT, Verily, IBM, Intel, Bayer, and Novartis., (© 2021 The Author(s).)

Objectives: The aim of this retrospective data collection study was to determine the effect size of dry mouth on the survival of restorations and teeth., Methods: The data were collected from the electronic patient files of City of Oulu Public Dental Services (Finland). Study population consisted of 71 dry mouth patients and 142 control patients. The survival of 3208 restorations were analyzed using Kaplan-Meier survival curves and multivariate Cox regression analysis with shared frailty for patients. Separate analyses were performed for the survival of the teeth., Results: The hazard ratio of restorations in dry mouth patients was 2.08 (95% CI: 1.65-2.63) compared to the control patients. For the dry mouth patients, the fixed prosthetic crowns outlasted composite fillings of all sizes, but the difference increased concomitantly with the filling size. The dry mouth patients had hazard ratio of 1.98 (95% CI: 1.02-3.82) for tooth extractions compared to the control patients. The teeth with fixed prosthetic crowns outlasted the teeth with direct restorative materials., Conclusions: The survival time of restorations and teeth are severely shortened in patients with dry mouth. Especially the survival time of the large composites is short in dry mouth patients whereas fixed prosthetic crowns have acceptable survival time also in dry mouth patients., Clinical Significance: When informing a dry mouth patient on the expected survival of a restoration or tooth, one should take into account that dry mouth patients´ restorations and teeth have severely shortened survival time., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objectives: This study aimed to compare the knowledge attained by third-year dental students in physical ergonomics altering live lectures and videos in teaching. The second aim was to investigate implementation of the theoretical knowledge on ergonomics into practice., Material and Methods: Forty-five students divided into two groups attended a live lecture (45 min) or viewed videos (45 min). After the first teaching session, the groups changed parts. All students answered a questionnaire with 13 true or false-questions on ergonomics at baseline and immediately after both teaching sessions. Friedman's test and Wilcoxon signed rank test were used to compare questionnaire scores of the student groups. Additionally, we photographed 17 randomly selected students 3 months after baseline during a simulation workshop on endodontics. We analyzed the photographs for ergonomic postures using a specific 12-point checklist., Results: At baseline, no difference in the knowledge between the two groups was discovered, when both scored 72%. After the first teaching session, significant improvement in both groups (p < .05) was found; and there was no statistically significant difference in the scores between the groups (88% in the lecture-first and 82% in the video-first group). After the second teaching session, the scores were similar in both groups. Overall all improvement in both groups was significant (p < .001). The photograph analysis showed half of the postures being in accord with the ergonomic guidelines., Conclusions: Both live lectures and videos showed similar outcomes in teaching ergonomics. Implementation of the knowledge on ergonomics is insufficient. Videos provide an easy-to-organize alternative to live lectures in teaching dental ergonomics. New means are needed to have dental students implement their knowledge on ergonomics into practice., (© 2020 The Authors. Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

Erosive tooth wear is defined as irreversible loss of dental tissues due to intrinsic or extrinsic acids, exacerbated by mechanical forces. Recent studies have suggested a higher prevalence of erosive tooth wear in males, as well as a genetic contribution to susceptibility to erosive tooth wear. Our aim was to examine erosive tooth wear by performing a genome-wide association study (GWAS) in a sample of the Northern Finland Birth Cohort 1966 (n = 1,962). Erosive tooth wear was assessed clinically using the basic erosive wear examination. A GWAS was performed for the whole sample as well as separately for males and females. We identified one genome-wide significant signal (rs11681214) in the GWAS of the whole sample near the genes PXDN and MYT1L. When the sample was stratified by sex, the strongest genome-wide significant signals were observed in or near the genes FGFR1, C8orf86, CDH4, SCD5, F2R, and ING1. Additionally, multiple suggestive association signals were detected in all GWASs performed. Many of the signals were in or near the genes putatively related to oral environment or tooth development, and some were near the regions considered to be associated with dental caries, such as 2p24, 4q21, and 13q33. Replications of these associations in other samples, as well as experimental studies to determine the biological functions of associated genetic variants, are needed., (© 2018 S. Karger AG, Basel.)

(Beginning of WHAT, WHEN, WHERE Summary Box:) What: The work-shop gathered almost 50 scientists from Europe and the United States to discuss the progress towards developing electromagnetic scattering databases for ice and snow particles in the microwave region, their applications, the physical approximations used to compute these scattering properties, and how remote sensing and in situ observations can be used to validate scattering datasets. One of the main priorities of the workshop was to foster communication between users and developers of scattering databases, and to define standards and conventions for scattering data structures and variables. When: 28-30 June 2017. Where: Cologne, Germany (END of what, when, where summary box) .

Objectives/aims: This cross-sectional study aimed to examine oral health and oral health-related habits among prisoners at the Pelso Prison in Finland., Materials and Methods: Participants in this cross-sectional study comprises 100 inmates. A calibrated dentist recorded the decayed, filled and missed teeth as well as periodontal status (bleeding-on-probing, pocket probing and Community Periodontal Index) among the participants ( n =100). Fifty inmates were also interviewed for marital status, education and oral health-related habits. The Ethical Committee of the Northern Ostrobothnia Hospital District and the Criminal Sanctions Agency approved the study protocol., Results: The participants were on average 35 years old and had 5 (s.d. 5.1) decayed teeth in need of restorative treatment, whereas DMFT was 17 (s.d. 8.9). Half of the study population had periodontal disease in need of professional treatment. Almost all reported brushing their teeth daily. Two-third ate sweets, one-third drank fizzy drinks and majority smoked every day. Almost two-third had used illicit drugs at some point of their lives. Almost all drunk alcohol once a week or more often. No statistically significant associations were discovered between dental treatment need and explanatory factors., Discussion: Prisoners appear to be a homogenous group with poor oral health and harmful health behaviours., Competing Interests: The authors declare no conflict of interest.

Background: The cardiac sodium channel Nav 1.5, encoded by the gene SCN5A, is associated with a wide spectrum of hereditary arrhythmias. The gain-of-function mutation p.I141V in SCN5A was identified in a large multigenerational family with exercise-induced polymorphic ventricular arrhythmias. The purpose of this study was to evaluate the molecular and clinical effects of flecainide administration on patients with this syndrome., Methods: Eleven p.I141V carriers who exhibited frequent multiformic premature ventricular complexes (PVCs) during exercise were subjected to exercise stress tests, both before and after intravenous infusion of 2 mg/kg flecainide. The in vitro effects of flecainide were evaluated using the patch-clamp technique with HEK293 cells expressing the Nav 1.5 channel., Results: The flecainide treatment significantly reduced the frequency of PVCs during and after exercise. Next, the sensitivity of the p.I141V mutant channel to flecainide was compared to that of the wild type channel. Perfusion of flecainide inhibited the peak and window currents in both groups., Conclusion: The clinical investigations of the affected patients, as well as the molecular and pharmacological characterization of the SCN5A p.I141V mutation, provide new evidence supporting the association of this mutation with exercise-induced polymorphic ventricular arrhythmias. These data also demonstrate that flecainide may serve as an effective treatment for the defect in Nav 1.5 that leads to an increased sodium window current., (© 2015 Wiley Periodicals, Inc.)

The capability to detect the state of snowflake riming reliably from remote measurements would greatly expand the understanding of its global role in cloud-precipitation processes. To investigate the ability of multifrequency radars to detect riming, a three-dimensional model of snowflake growth was used to generate simulated aggregate and crystal snowflakes with various degrees of riming. Three different growth scenarios, representing different temporal relationships between aggregation and riming, were formulated. The discrete dipole approximation was then used to compute the radar backscattering properties of the snowflakes at frequencies of 9.7, 13.6, 35.6, and 94 GHz. In two of the three growth scenarios, the rimed snowflakes exhibit large differences between the backscattering cross sections of the detailed three-dimensional models and the equivalent homogeneous spheroidal models, similarly to earlier results for unrimed snowflakes. When three frequencies are used simultaneously, riming appears to be detectable in a robust manner across all three scenarios. In spite of the differences in backscattering cross sections, the triple-frequency signatures of heavily rimed particles resemble those of the homogeneous spheroids, thus explaining earlier observational results that were compatible with such spheroids.

Background: Over the past 15 years, a myriad of mutations in genes encoding cardiac ion channels and ion channel interacting proteins have been linked to a long list of inherited atrial and ventricular arrhythmias. The purpose of this study was to identify the genetic and functional determinants underlying exercise-induced polymorphic ventricular arrhythmia present in a large multigenerational family., Methods and Results: A large 4-generation family presenting with exercise-induced polymorphic ventricular arrhythmia, which was followed for 10 years, was clinically characterized. A novel SCN5A mutation was identified via whole exome sequencing and further functionally evaluated by patch-clamp studies using human embryonic kidney 293 cells. Of 37 living family members, a total of 13 individuals demonstrated ≥50 multiformic premature ventricular complexes or ventricular tachycardia upon exercise stress tests when sinus rate exceeded 99±17 beats per minute. Sudden cardiac arrest occurred in 1 individual during follow-up. Exome sequencing identified a novel missense mutation (p.I141V) in a highly conserved region of the SCN5A gene, encoding the Nav1.5 sodium channel protein that cosegregated with the arrhythmia phenotype. The mutation p.I141V shifted the activation curve toward more negative potentials and increased the window current, whereas action potential simulations suggested that it lowered the excitability threshold of cardiac cells., Conclusions: Gain-of-function of Nav1.5 may cause familial forms of exercise-induced polymorphic ventricular arrhythmias., (© 2014 American Heart Association, Inc.)

Fondaparinux, indirect factor Xa (FXa) inhibitor, is recommended for thromboprophylaxis for high-risk patients undergoing major orthopedic surgery. We evaluated the prothrombotic state and anticoagulant intensity of fondaparinux (2.5 mg daily) after total hip replacement (THR). Twenty patients underwent THR - seven bilateral and 13 unilateral. Blood samples were collected preoperatively and at 6 h, 8 h (2 h after fondaparinux), 1 day (12-14 h after fondaparinux), and 4 weeks (12-14 h after fondaparinux) postoperatively. Antithrombin (AT), fibrinogen, factor VIII activity, coagulation times, thrombin-AT (TAT) complex, D-dimer, C-reactive protein, prothrombinase-induced clotting time (PiCT) and anti-Xa activity were measured. The latter two were also tested after plasma spiking with fondaparinux 0-1.25 μg/ml. In spiked prophylactic fondaparinux samples (0-0.25 μg/ml), PiCT and anti-Xa activity correlated (r = 0.84) better than in the patient samples (r = 0.35). On the first day, anti-Xa activity and PiCT dissociated, and PiCT lost sensitivity for fondaparinux. AT decreased but stayed within the normal range, whereas TAT complex and D-dimer peaked at 6 h as signs of thrombin generation. On the first postoperative day, TAT and D-dimer halved. Bilateral THR associated with higher TAT and D-dimer levels up to 4 weeks. Perioperative FVIII levels were not affected, but were elevated in both groups (range 191-211%) after 4 weeks. Anti-Xa activity detected prophylactic fondaparinux with higher sensitivity than PiCT in vitro, but even more so in vivo. Thus, PiCT is not the method of choice to assess fondaparinux at least in association with THR. THR, bilateral more than unilateral, increased thrombin generation and D-dimer 7-11-fold early after surgery. Factor VIII activity and D-dimer remained elevated even after 4 weeks despite the compliant thromboprophylaxis with fondaparinux.

The PyTMatrix package was designed with the objective of providing a simple, extensible interface to T-Matrix electromagnetic scattering calculations performed using an extensively validated numerical core. The interface, implemented in the Python programming language, facilitates automation of the calculations and further analysis of the results through direct integration of both the inputs and the outputs of the calculations to numerical analysis software. This article describes the architecture and design of the package, illustrating how the concepts in the physics of electromagnetic scattering are mapped into data and code models in the computer software. The resulting capabilities and their consequences for the usability and performance of the package are explored.

Carbonic anhydrase VI (CAVI) is the only secreted isozyme of the α-carbonic anhydrase family, which catalyzes the reversible reaction [Formula in text]. It appears that CAVI protects teeth and gastrointestinal mucosa by neutralizing excess acidity. However, the evidence for this physiological function is limited, and CAVI may have additional functions that have yet to be discovered. To explore the functions of CAVI more fully, we generated Car6 (-/-) mice and analyzed Car6 (-/-) mutant phenotypes. We also examined transcriptomic responses to CAVI deficiency in the submandibular gland, stomach, and duodenum of Car6 (-/-) mice. Car6 (-/-) mice were viable and fertile and had a normal life span. Histological analyses indicated a greater number of lymphoid follicles in the small intestinal Peyer's patches. A total of 94, 56, and 127 genes were up- or down-regulated in the submandibular gland, stomach, and duodenum of Car6 (-/-) mice, respectively. The functional clustering of differentially expressed genes revealed a number of altered biological processes. In the duodenum, the significantly affected biological pathways included the immune system process and retinol metabolic processes. The response to oxidative stress and brown fat cell differentiation changed remarkably in the submandibular gland. Notably, the submandibular gland, stomach, and duodenum shared one important transcriptional susceptibility pathway: catabolic process. Real-time PCR confirmed an altered expression in 14 of the 16 selected genes. The generation and of Car6 (-/-) mice and examination of the effects of CAVI deficiency on gene transcription have revealed several affected clusters of biological processes, which implicate CAVI in catabolic processes and the immune system response.

This paper estimates and interprets empirical shifts in the gender composition of immigrants to add to scholarship about the gendering of international migrations over time. We map shifts in gender ratios using micro-level data that permit us to create age-standardized estimates among adult foreign born stock living in the United States since 1850 and in 26 other nations worldwide since 1960. We examine regional and national variations in these shifts, and ask whether and how the gendered composition of foreigners from diverse origins in the United States – the nation that has received the largest populations of migrants for over a century – differs from other nations that receive large numbers of immigrants. We also examine recent variations in gender ratios among immigrants living in six regional destination countries. Results show substantial variation in the gender composition of foreign-born populations, and they offer a starting point for examining causes and consequences in future research.

Human glandular kallikrein (KLK2) is a highly prostate-specific serine protease, which is mainly excreted into the seminal fluid, but part of which is also secreted into circulation from prostatic tumors. Since the expression level of KLK2 is elevated in aggressive tumors and it has been suggested to mediate the metastasis of prostate cancer, inhibition of the proteolytic activity of KLK2 is of potential therapeutic value. We have previously identified several KLK2-specific linear peptides by phage display technology. Two of its synthetic analogs, A R R P A P A P G (KLK2a) and G A A R F K V W W A A G (KLK2b), show specific inhibition of KLK2 but their sensitivity to proteolysis in vivo may restrict their potential use as therapeutic agents. In order to improve the stability of the linear peptides for in vivo use, we have prepared cyclic analogs and compared their biological activity and their structural stability. A series of cyclic variants with cysteine bridges were synthesized. Cyclization inactivated one peptide (KLK2a) and its derivatives, while the other peptide (KLK2b) and its derivatives remained active. Furthermore, backbone cyclization of KLK2b improved significantly the resistance against proteolysis by trypsin and human plasma. Nuclear magnetic resonance studies showed that cyclization of the KLK2b peptides does not make the structures more rigid. In conclusion, we have shown that backbone cyclization of KLK2 inhibitory peptides can be used to increase stability without losing biological activity. This should render the peptides more useful for in vivo applications, such as tumor imaging and prostate cancer targeting., (Copyright (c) 2007 European Peptide Society and John Wiley & Sons, Ltd.)

The molecular mechanism governing the regulated secretion of most exocrine tissues remains elusive, although VAMP8/endobrevin has recently been shown to be the major vesicular SNARE (v-SNARE) of zymogen granules of pancreatic exocrine acinar cells. In this article, we have characterized the role of VAMP8 in the entire exocrine system. Immunohistochemical studies showed that VAMP8 is expressed in all examined exocrine tissues such as salivary glands, lacrimal (tear) glands, sweat glands, sebaceous glands, mammary glands, and the prostate. Severe anomalies were observed in the salivary and lacrimal glands of VAMP8-null mice. Mutant salivary glands accumulated amylase and carbonic anhydrase VI. Electron microscopy revealed an accumulation of secretory granules in the acinar cells of mutant parotid and lacrimal glands. Pilocarpine-stimulated secretion of saliva proteins was compromised in the absence of VAMP8. Protein aggregates were observed in mutant lacrimal glands. VAMP8 may interact with syntaxin 4 and SNAP-23. These results suggest that VAMP8 may act as a v-SNARE for regulated secretion of the entire exocrine system.

Purpose: To estimate the repeatability of refractive error measurement (REM) in a clinical environment in cataractous, pseudophakic and healthy eyes., Methods: The refractive error of patients referred for cataract surgery or consultation measured by ophthalmic professionals was re-examined and the measurement results were compared. A total of 99 eyes from 99 persons (41 cataractous, 36 pseudophakic and 22 healthy eyes) with visual acuity (VA) of 0.3-1.3 (logMAR 0.52 to - 0.11) were included. The differences between measurements 1 and 2 were calculated as 3-dimensional vector values and spherical equivalents (SEs) and expressed as the coefficient of repeatability (CR). The mean time interval between the first and second examinations was 45 days., Results: The CRs for all eyes for vertical (V), torsional (T) and horizontal (H) vectors were 0.74 D, 0.34 D and 0.93 D, respectively. The CR of SE for all eyes was 0.74 D. Eyes with lower VA (0.3-0.45) had larger variability in vector and SE values but the differences between VA groups were not statistically significant. The difference in the mean defocus equivalent (DE) between measurements 1 and 2 was, however, significantly greater in the group with lower VA. In all VA groups the mean difference vector was very close to the zero vector, which means that there was no systematic difference., Conclusions: Repeatability of refractive error measurements in clinical settings has a certain degree of variability. In this series, the variability in eyes with better VA was not great and was in accordance with earlier findings in healthy eyes. Eyes with lower VA had greater variability due to greater tolerance to defocus. Thus, conclusions concerning changes in the refractive state and the need to make changes in the refractive correction of eyes with poorer vision should be made with caution.

Human kallikrein 2 (hK2) is a serine protease produced by the secretory epithelial cells in the prostate. Because hK2 activates several factors participating in proteolytic cascades that may mediate metastasis of prostate cancer, modulation of the activity of hK2 is a potential way of preventing tumor growth and metastasis. Furthermore, specific ligands for hK2 are potentially useful for targeting and imaging of prostate cancer and for assay development. We have used enzymatically active recombinant hK2 captured by a monoclonal antibody exposing the active site of the enzyme to screen phage display peptide libraries. Using libraries expressing 10 or 11 amino acids long linear peptides, we identified six different peptides binding to hK2. Three of these were shown to be specific and efficient inhibitors of the enzymatic activity of hK2 toward a peptide substrate. Furthermore, the peptides inhibited the activation of the proform of prostate-specific antigen by hK2. Amino acid substitution analyses revealed that motifs of six amino acids were required for the inhibitory activity. These peptides are potentially useful for treatment and targeting of prostate cancer.

Purpose: To estimate the random measurement error in visual acuity (VA) determination in the clinical environment in cataractous, pseudophakic and healthy eyes., Methods: The VAs of patients referred for cataract surgery or consultation by ophthalmic professionals were re-examined and the VA results for distance using projector acuity charts were compared. Refractive errors were also remeasured. A total of 99 eyes (41 cataractous, 36 pseudophakic and 22 healthy eyes) were examined. The healthy comparison group consisted of hospital staff. Only one eye of each person and eyes with Snellen VAs of 0.3-1.3 (logMAR 0.52 to - 0.11) were included. The mean time interval between the first and second examinations was 45 days., Results: The estimated standard deviation of measurement error (SDME) of repeated VA measurements of all eyes was logMAR 0.06. Eyes with the lowest VA (0.3-0.45) had the largest variability (SDME logMAR 0.09), and eyes with VA > or = 0.7 had the smallest (SDME logMAR 0.04). The variability may be partly explained by the line size progression in lower VAs, partly by the difference in the remeasurement of the refractive error. The difference in the average VA between examinations 1 and 2 (logMAR 0.15 versus 0.12) was considered to be of some interest because it indicates that some learning effect is possible., Conclusion: Visual acuity results in clinical settings have a certain degree of inherent variability. In this series variability ranged from SDME logMAR 0.04 (eyes with good vision) to logMAR 0.09 (in the lower vision group) in the Snellen VA range of 0.3-1.3. Changes should be judged with caution, especially in cases of decreased VA.

Prostate-specific antigen (PSA), a member of the kallikrein sub-group of the trypsin serine protease family, is a widely used marker for prostate cancer. Several sequences with specific binding to PSA have been identified by using phage display peptide libraries. The GST-fusion proteins of the characterized sequences have been shown to increase the enzyme activity of PSA to a synthetic substrate. The corresponding three cyclic synthetic analogues CVFTSNYAFC (A-1), CVFAHNYNYLVC (B-2) and CVAYCIEHHCWTC (C-4) have similar PSA promoting activity. Despite differences in the amino acid sequences, all three peptides bind to the same region of PSA. The conformation of the peptides was investigated by proton NMR spectroscopy. In addition, alanine replacement was used to characterize the prerequisites for binding. It is proposed that interactions with PSA are based on the aromatic and hydrophobic features of the amino acid side chains. Furthermore, it is suggested that peptides form beta-turn structures forced by cysteine bridges directing important aromatic side chains to the same side of the turn-structure.

Prostate specific antigen (PSA) is the most important marker for prostate cancer. Antibodies against minor variants of PSA may be useful in the development of novel diagnostic tests for prostate cancer, but it has been difficult to produce such antibodies by protein immunization. In this study, we have compared the characteristics of monoclonal antibodies (MAbs) obtained by genetic immunization with those obtained by protein immunization. The whole coding region of PSA-cDNA was cloned in a mammalian expression vector pCDNA-3. Six mice were immunized four times by intra-muscular (i.m.) injection of the PSA-pCDNA3 plasmid. The MAbs produced were characterized with respect to subclass, epitope specificity, binding to various molecular forms of PSA and affinity. After intra-muscular injection of DNA, anti-PSA antibodies were detected in the serum of all mice, but the antibody titers were markedly lower than after protein immunization. After fusion of the spleen cells from the mice, five hybridomas producing MAbs to PSA were obtained. The MAbs were of IgG1 and IgG2a isotype and they all recognized equally different forms of free PSA, namely enzymatically active, nicked and proPSA. Epitope mapping showed that these MAbs reacted with the same antigenic regions as those obtained by protein immunization. Thus, genetic immunization leads to production of anti PSA MAbs with similar characteristics to those obtained by immunizing with PSA protein. As applied in the present study, it is less efficient than protein immunization, but it is a useful technique when the antigen is not available in the quantities needed for immunization.

This study evaluated the applicability of the family economic stress model (FESM) in understanding the influences of economic hardship on child mental health during a nationwide economic recession in Finland. The information was gathered from 527 triads of 12-year-olds and their mothers and fathers from a population sample. The structural equation models showed that the FESM fit the data well, indicating its generalizability in Finnish society. The results confirmed that a reduction in disposable family income constitutes a risk for child mental health through increased economic pressure and negative changes in parental mental health, marital interaction, and parenting quality. Controlling the children's prerecession mental health substantiated that economic hardship can lead to deterioration in children's mental health. Alternative models based on fully recursive analyses revealed reciprocal influences between parents and their children over time: Children's prerecession mental health problems predicted compromised parenting, which in turn contributed to children's internalizing and externalizing symptoms during the recession.

Background: Prostate-specific antigen (PSA) is a serine protease with highly prostate-specific expression and an important marker for prostate cancer. We have previously identified novel PSA-binding peptides that enhance the enzymatic activity of PSA when produced as fusion proteins., Method: PSA-binding peptides and derivatives with a spacer were chemically synthesized and used to prepare an affinity column, which was used to fractionate PSA in seminal plasma, serum, and LNCap cell culture medium., Results: Approximately 67% of seminal plasma PSA bound to the peptide affinity column and was eluted under mild conditions. Eluted PSA was intact and enzymatically active while the unbound fraction mainly contained various nicked forms. ProPSA from LNCap cells bound to the peptide column only after activation by trypsin., Conclusions: PSA-binding peptides can be used to separate enzymatically active and inactive forms of PSA. Thus the peptides are potentially useful as ligands for development of methods for specific detection of active free PSA., (Copyright 2003 Wiley-Liss, Inc.)

Background: Determinations of certain forms of prostate-specific antigen (PSA) have been shown to increase the specificity for prostate cancer (PCa). One such variant, proteolytically active PSA, is a potentially useful tumor marker, but it is not specifically recognized by antibodies. Using phage display libraries, we previously identified a "family" of peptides that bind specifically to active PSA. We used these to develop an immunopeptidometric assay (IPMA) that specifically detects this form of PSA., Methods: Microtitration plates coated with a PSA antibody were used to capture PSA, and a PSA-binding glutathione S-transferase (GST) fusion peptide was used as a tracer. Bound tracer was detected with an antibody to GST labeled with a europium chelate. PSA isoenzymes with high and low enzymatic activity were used to study binding specificity., Results: The IPMA detected enzymatically active PSA but not internally cleaved PSA and pro-PSA, which are enzymatically inactive. The assay detected 1-10% of free PSA in serum from PCa patients., Conclusions: Peptides identified by phage display can be used to develop assays with unique specificities for enzymatically active PSA. IPMA represents a new assay principle with wide potential utility.

Background: A major portion of prostate-specific antigen exists in circulation as a complex with alpha(1)-antichymotrypsin (PSA-ACT), whereas a minor part is free (fPSA). The proportion of PSA-ACT is increased in prostate cancer (PCa), but immunologic determination of PSA-ACT is hampered by a background produced by nonspecific adsorption of ACT to the solid phase. To reduce the nonspecific interference, we produced an antibody specific for complexed ACT and developed immunofluorometric assays (IFMAs) for simultaneous measurement of fPSA + PSA-ACT (fPSA/PSA-ACT) and PSA-ACT + total PSA (tPSA, PSA-ACT/tPSA)., Methods: Monoclonal antibodies (MAbs) were produced by immunization with PSA-ACT. The dual-label time-resolved IFMAs for fPSA/PSA-ACT and PSA-ACT/tPSA used a capture MAb to tPSA, an Eu(3+)-labeled MAb to fPSA or complexed ACT, and an Sm(3+)-labeled MAb to complexed ACT or to tPSA as tracer antibodies. The clinical utility was evaluated using serum samples from individuals with or without PCa with PSA concentrations of 2.0-20.0 micro g/L., Results: One MAb (1D10) showed low cross-reactivity with free ACT and cathepsin G-ACT. A sandwich assay for PSA-ACT with 1D10 as tracer had a detection limit of 0.05 micro g/L, and with this assay, PSA-ACT was undetectable in female sera. The detection limit for fPSA was 0.004 micro g/L. Determinations of the ratio of fPSA to PSA-ACT and the proportions of fPSA/tPSA and PSA-ACT/tPSA provided the same clinical specificity for PCa and provided significantly better clinical specificity than did tPSA., Conclusions: Background problems observed in earlier PSA-ACT assays are eliminated by the use of a MAb specific for complexed ACT as a tracer. The same clinical validity can be obtained by determination of fPSA or PSA-ACT together or in combination with tPSA.

Background: Prostate-specific antigen (PSA) is the most important marker for prostate cancer, but PSA concentrations determined by various assays can differ significantly because of differences in specificity of the antibodies used. To identify epitopes recognized by various monoclonal antibodies (MAbs) to PSA, we have isolated peptides that react with the paratopes of these., Methods: Six anti-PSA MAbs representing three major epitope groups were screened with five cyclic phage display peptide libraries. After selection, the peptide sequences were determined by sequencing of the relevant part of viral DNA. Binding of the phage peptides to the MAbs was monitored by immunoassay., Results: For each MAb, several paratope-binding peptides with distinct sequence motifs were identified, but only approximately 10% showed similarity with the PSA sequence. Some of these correctly predicted the location of the epitopes. By sequential panning of the library with two closely related MAbs, we identified peptides reacting equally with both MAbs. When analyzed against a large panel of PSA MAbs, the peptides generally showed restricted specificity toward the MAb used for selection, but some peptides bound to several related MAbs., Conclusions: Most of the cyclic peptides selected with PSA MAbs are specific for the MAb used for selection and do not resemble any sequence on the antigen. Peptides reactive with two MAbs recognizing the same epitope can be obtained by sequential panning. This method can be used to predict the location of some epitopes, but additional methods are needed to confirm the result.

Semenogelin plays an important role in sperm clotting and is degraded into smaller fragments by prostate-specific antigen (PSA) during clot liquefaction. Semenogelin and its fragments inhibit sperm motility in vitro. We studied the expression of semenogelin I mRNA and its localization in various tissues of the male genital tract. We also studied semenogelin concentrations with respect to sperm parameters and the outcome of in vitro fertilization. Semenogelin protein was detected by immunohistochemical staining and semenogelin I mRNA was detected by Northern blot analysis in the seminal vesicles and ampullary part of the vas deferens, whereas specimens from the prostate, epididymis, testis, and the female genital tract were negative. Using monoclonal antibodies against semenogelin, an immunofluorometric assay was developed to measure semenogelin levels in seminal plasma and to evaluate possible correlations with sperm parameters and fertilization in vitro. No correlation was found between the semenogelin concentration and the volume of the ejaculate, sperm concentration, sperm motility, or in vitro fertilization rate. Semenogelin levels were positively correlated with the total protein concentration in seminal plasma, and there was an inverse correlation between the concentration of semenogelin and that of PSA. The levels of semenogelin appear to bear no relationship to the in vitro fertilization capacity of the spermatozoa.

Purpose: We investigate the validity of prostate specific antigen (PSA) as a screening test for prostate cancer., Materials and Methods: A registry of serum samples drawn from 1968 to 1976 from 21,387 men was linked to the Finnish Cancer Registry. During followup from 1968 to 1991, 104 prostate cancers were identified. A matched case control design with incidence density sampling and nested in the serum sample bank was applied, and PSA was assessed., Results: The estimated sensitivity of the test was 44% and specificity 94% at a cutoff of 4.0 microg./l. in the total material. The sensitivity had improved to 86% in patients diagnosed in 5 years after the sample drawing. The test had a better sensitivity (93%) and specificity (96%) in men younger than 65 years at the time of the sample drawing compared to those older. The sensitivity further improved to 100% with a cutoff of 2.5 microg./l., Conclusions: PSA is a valid screening test for prostate cancer, which compares favorably with mammography for breast cancer. However, until an effect on mortality has been shown, routine screening cannot be recommended.

In addition to essential nutrients, human milk contains several classes of bioactive factors such as enzymes, hormones, and growth factors, many of which are implicated in infantile growth and development. Secretory carbonic anhydrase isoenzyme VI (CA VI) has been identified earlier as an essential component of mammalian saliva, and we demonstrate here by using biochemical and immunohistochemical techniques that it is also an elementary component of milk. The 42-kDa glycopolypeptide purified from human milk in CA inhibitor affinity chromatography shared 100% homology with salivary CA VI in the protein sequence analysis (40% coverage), and its digestion with PNGase F resulted in a polypeptide backbone similar in size to salivary CA VI. Quantification of CA VI in milk by using a time-resolved immunofluorometric assay revealed an approximately eight-times-higher concentration in human colostrum than in mature milk, the latter corresponding to the levels previously detected in human saliva. The high concentration in the colostrum, in particular its functional and structural stability in an acidic milieu, and its growth-supporting role in the taste buds suggest that milk CA VI is an essential factor in normal growth and development of the infant alimentary tract.

Salivary carbonic anhydrase VI (CA VI) appears to contribute to taste function by protecting taste receptor cells (TRCs) from apoptosis. The serous von Ebner's glands locating in the posterior tongue deliver their saliva into the bottom of the trenches surrounding the TRC-rich circumvallate and foliate papillae. Because these glands deliver their saliva directly into the immediate vicinity of TRCs, we investigated whether CA VI is secreted by the von Ebner's glands, using immunochemical techniques. The immunohistochemical results showed that CA VI is present in the serous acinar cells, ductal cells, and ductal content of von Ebner's glands and in the demilune and ductal cells plus ductal content of rat lingual mucous glands. More importantly, CA VI was also detected in taste buds and in the taste pores. Western blotting of saliva collected from the orifices of human von Ebner's glands and CAs purified from rat von Ebner's glands confirmed that CA VI is expressed in these glands and secreted to the bottom of the trenches surrounding the circumvallate and foliate papillae. These findings are consistent with the hypothesis that locally secreted CA VI is implicated in the paracrine modulation of taste function and TRC apoptosis. (J Histochem Cytochem 49:657-662, 2001)

Purpose: We assess whether the complex between prostate specific antigen (PSA) and alpha1-protease inhibitor in serum can be used to reduce further the number of false-positive PSA screen results independent of total and free PSA., Materials and Methods: Sera from 304 consecutive screen positive subjects, including 78 with and 226 without prostate cancer, and serum PSA of 4 to 10 microg./l. or higher in the Finnish, randomized, population based prostate cancer screening trial were analyzed for PSA-alpha-protease inhibitor, and total and free PSA. Main outcome measures were specificity, sensitivity and area under receiver operating characteristics curve for proportions of free PSA and PSA-alpha 1-protease inhibitor, and for a combination of these among screen positive cases., Results: The proportion of serum PSA-alpha 1-protease inhibitor of total PSA was lower in cancer cases than in controls (0.9% versus 1.6%, p <0.001). Logistic regression analysis of total PSA, free PSA and PSA-alpha 1-protease inhibitor showed that PSA-alpha 1-protease inhibitor in serum was an independent variable for discrimination between subjects with and without prostate cancer (p = 0.006) in the PSA range of 4 to 10 microg./l. The proportion of PSA-alpha 1-protease inhibitor alone improved specificity less than the proportion of free PSA but when these were combined by logistic regression they performed better than the proportion of free PSA alone at sensitivities of 85% to 95% (p <0.001)., Conclusions: Serum PSA-alpha 1-protease inhibitor improves the specificity of total and free PSA in a screening population with total PSA 4 to 10 microg./l.

Prostate-specific antigen (PSA) is a serine protease with highly prostate-specific expression. Measurement of PSA in serum is widely used for diagnosis and monitoring of prostate cancer. PSA dissolves the seminal gel forming after ejaculation. It has been suggested to mediate invasion and metastasis of prostate cancer but also to exert antiangiogenic activity. We have identified peptides specific for PSA by screening cyclic phage display peptide libraries. PSA-binding peptides were isolated from four different libraries and produced as a fusion protein with glutathione S-transferase (GST). The phage and fusion proteins were shown to bind to PSA specifically as indicated by lack of binding to other serine proteinases. A peptide with four cysteines showed the highest affinity for PSA. Zn2+, an inhibitor of PSA activity, increased the affinity of the peptides to PSA. The binding specificity was characterized by cross-inhibition using monoclonal anti-PSA antibodies of known epitope specificities. The peptides bound to the same region as mAbs specific for free PSA indicating that they bind close to the active site of the enzyme. The peptides enhanced the enzyme activity of PSA against a chromogenic substrate. These results show that peptides binding to PSA and modulating its enzyme activity can be developed by phage display technique. The peptides have the potential to be used for identification of PSA variants and for imaging and targeting of prostatic tumors.

Prostate-specific antigen (PSA) is a tissue-specific serine protease which forms complexes with protease inhibitors such as alpha 1-antichymotrypsin and alpha 2-macroglobulin. We have studied the interaction between PSA and alpha 1-protease inhibitor (API) in vitro and found that 15% of the added PSA binds to API while the majority of API is cleaved between Met358 and Ser359 when PSA is incubated with a 5-fold excess of API at 37 degrees C for 7 days. The complex between PSA and API (PSA-API) formed in vitro displays the same chromatographic behavior, molecular size and immunoreactivity as endogenous PSA-API occurring in serum, indicating that they are identical. PSA-API can be detected in serum by a time-resolved immunofluorometric assay (IFMA), in which a monoclonal antibody to PSA is used as a catcher and a polyclonal antibody to API labeled with a Eu-chelate is used as a tracer. Purified PSA-API formed in vitro is used as a calibrator. PSA-API in serum represents 1.0-7.9% (median 2.4%) of total PSA (tPSA) in prostate cancer (PCa, n = 82) and 1.3-12.2% (median 3.6%, p < 0.01) in patients with benign prostatic hyperplasia (BPH, n = 66). The IFMA for PSA-API in serum is hampered by a variable background, which is caused by non-specific adsorption of the huge excess of API in serum to the solid phase. The background can be determined by an assay using the same tracer as in the IFMA for PSA-API but PSA-unrelated antibody on the solid phase. The background signal is subtracted from the PSA-API signal. The clinical utility of PSA-API in serum has been evaluated in PSA-positive subjects from the Finnish PCa screening trial. After subtraction of the background, the proportion of PSA-API in relation to tPSA is lower in PCa than in controls, 0.9% vs. 1.6%, respectively (p < 0.001). Logistic regression analysis showed that the concentration of PSA-API was independent of the proportion of free PSA as a diagnostic variable among subjects with a tPSA of 4-10 micrograms/l (p = 0.009). The probability of PCa calculated by logistic regression using the concentration of PSA-API and the proportion of free PSA in serum significantly improved cancer specificity at high sensitivity levels (85-95%) as compared to the proportion of free PSA alone.

The measurement of serum prostate-specific antigen (PSA) is widely used for the detection and management of patients with prostate cancer. Many studies on the validity of PSA as a marker for prostate cancer are performed on clinical samples that have been stored frozen for years. We have studied the stability of free (F), total (T) and complexed (C) PSA immunoreactivity and the proportion of free to total PSA (F/T) in serum after melting sera stored at -20 degrees C for 2 years and 2 weeks, respectively. In contrast to the decrease in PSA-F and F/T observed in fresh samples, PSA-C decreased and PSA-F increased in a time-dependent fashion after thawing samples that had been kept frozen for 2 years. This caused a net decrease in PSA-T and an increase in F/T. These results suggest that even though serum PSA is fairly stable during short-term storage, long-term storage at -20 degrees C reduces the stability of PSA immunoreactivity. Thus, results obtained on samples stored for prolonged times at -20 degrees C should be interpreted with caution. Because of the changes in PSA-F and F/T in both fresh and archival samples stored unfrozen, it is recommended that sera are melted only for the period required for pipetting the samples., (Copyright 2000 S. Karger AG, Basel)