Per- and poly-fluoroalkyl substances in commercial organic eggs via fishmeal in feed

Chicken eggs can be a significant source of human PFAS exposure. A survey of PFAS in commercial eggs from larger farms across Denmark showed the absence or low contents of PFAS in free-range and barn eggs. However, organic eggs from eight farms collected in September 2022 had a similar profile of nine PFASs with a predominance of odd over even carbon length PFCAs. Farm 11-13 e.g. had egg yolk ng/g concentrations of PFOA 0.07 ± 0.02; PFNA 0.37 ± 0.04; PFDA 0.13 ± 0.00; PFUnDA 0.22 ± 0.04; PFDoDA 0.06 ± 0.02; PFTrDA 0.15 ± 0.04; PFTeDA 0.02 ± 0.02; PFHxS 0.10 ± 0.04; PFOS 2.62 ± 0.11. Normalised to PFOS, the relative sum of other PFAS showed no difference between the eight organic egg samples, but significant differences between mean individual PFASs (p = 1.4E-25), reflecting a similar profile. The PFAS found in two fishmeal samples with the same origin as the fishmeal used for the organic feed production, could account for the contents in the eggs via estimated transfer from the feed. Furthermore, the estimated transfer from concentration in feed to concentration in egg increased with the carbon length of the PFCA. Exposure (95th percentile) of ∑4PFAS (PFOA, PFNA, PFHxS, PFOS) solely from consumption of 311 g ∼ 5-6 organic eggs/week was for children 4-9 years 10.4 ng/kg bw, i.e. a significant exceedance of the tolerable weekly intake of 4.4 ng/kg bw established by the European Food Safety Authority. Based on the PFAS exposures from organic egg consumption, the organic egg producers decided voluntarily to cease adding fishmeal to the feed. Since the feed-to-egg half-lives are ≤1 week for PFOA, PFOS, and PFHxS, the removal of fishmeal as a feed ingredient should eliminate PFAS after 1-2 months. This was demonstrated in analyses of ten organic egg samples collected by the authorities without PFAS in eight and with 0.1 and 0.4 ng/g ∑4PFAS in two samples.

Children’s distal forearm fractures: a population-based epidemiology study of 4,316 fractures

Aims

The aim of this study was to report a complete overview of both incidence, fracture distribution, mode of injury, and patient baseline demographics of paediatric distal forearm fractures to identify age of risk and types of activities leading to injury.

Methods

Population-based cohort study with manual review of radiographs and charts. The primary outcome measure was incidence of paediatric distal forearm fractures. The study was based on an average at-risk population of 116,950. A total number of 4,316 patients sustained a distal forearm fracture in the study period. Females accounted for 1,910 of the fractures (44%) and males accounted for 2,406 (56%).

Results

The overall incidence of paediatric distal forearm fractures was 738.1/100,000 persons/year (95% confidence interval (CI) 706/100,000 to 770/100,000). Female incidences peaked with an incidence of 1,578.3/100,000 persons/year at age ten years. Male incidence peaked at age 13 years, with an incidence of 1,704.3/100,000 persons/year. The most common fracture type was a greenstick fracture to the radius (48%), and the most common modes of injury were sports and falls from ≤ 1 m. A small year-to-year variation was reported during the five-year study period, but without any trends.

Conclusion

Results show that paediatric distal forearm fractures are very common throughout childhood in both sexes, with almost 2% of males aged 13 years sustaining a forearm fracture each year.

Cite this article: Bone Jt Open 2022;3(6):448–454.

Impact of Tellurite on the Metabolism of Paenibacillus pabuli AL109b With Flagellin Production Explaining High Reduction Capacity

Tellurium (Te) is a metalloid with scarce and scattered abundance but with an increased interest in human activity for its uses in emerging technologies. As is seen for other metals and metalloids, the result of mining activity and improper disposal of high-tech devices will lead to niches with increased abundance of Te. This metalloid will be more available to bacteria and represent an increasing selective pressure. This environmental problem may constitute an opportunity to search for microorganisms with genetic and molecular mechanisms of microbial resistance to Te toxic anions. Organisms from Te-contaminated niches could provide tools for Te remediation and fabrication of Te-containing structures with added value. The objective of this study was to determine the ability of a high metal-resistant Paenibacillus pabuli strain ALJ109b, isolated from high metal content mining residues, to reduce tellurite ion, and to evaluate the formation of metallic tellurium by cellular reduction, isolate the protein responsible, and determine the metabolic response to tellurite during growth. P. pabuli ALJ109b demonstrated to be resistant to Te (IV) at concentrations higher than reported for its genus. It can efficiently remove soluble Te (IV) from solution, over 20% in 8 h of growth, and reduce it to elemental Te, forming monodisperse nanostructures, verified by scattering electron microscopy. Cultivation of P. pabuli ALJ109b in the presence of Te (IV) affected the general protein expression pattern, and hence the metabolism, as demonstrated by high-throughput proteomic analysis. The Te (IV)-induced metabolic shift is characterized by an activation of ROS response. Flagellin from P. pabuli ALJ109b demonstrates high Te (0) forming activity in neutral to basic conditions in a range of temperatures from 20°C to 37°C. In conclusion, the first metabolic characterization of a strain of P. pabuli response to Te (IV) reveals a highly resistant strain with a unique Te (IV) proteomic response. This strain, and its flagellin, display, all the features of potential tools for Te nanoparticle production.

Maternal age at menarche and pubertal development in sons and daughters: a Nationwide Cohort Study

STUDY QUESTION

Is maternal age at menarche associated with pubertal development in sons and daughters?

SUMMARY ANSWER

Maternal age at menarche was associated with pubertal development in both sons and daughters.

WHAT IS KNOWN ALREADY

Studies have shown that age at menarche is greatly inherited from mother to daughter, but it remains largely unknown to what extent age at menarche in mothers is associated with timing of puberty in sons.

STUDY DESIGN, SIZE, DURATION

In this population-based study we used data from the Puberty Cohort nested within the Danish National Birth Cohort. Live-born singletons aged 11 were followed from 2012 to 2016.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In total, 15 822 children (7697 sons and 8125 daughters) gave half-yearly information on puberty from the age of 11 years until full sexual maturity or 18 years of age through self-administrated questionnaires (participation rate 71%). Information on maternal age at menarche was reported by the mothers during pregnancy. Maternal age at menarche was used both as a continuous and as a categorical variable (earlier, same time or later than peers). A multivariable regression model for interval-censored data was used.

MAIN RESULTS AND THE ROLE OF CHANCE

Maternal age at menarche was positively associated with timing of genital development, pubic hair development, first ejaculation of semen, voice break, axillary hair development and acne in sons, and with timing of breast development, pubic hair development, menarche, axillary hair development and acne in daughters. In sons, the associations were of similar strength for all pubertal markers, whereas in daughters, the associations were strongest for breast development and menarche.

LIMITATIONS, REASONS FOR CAUTION

Age at menarche was recalled during pregnancy. However, studies indicate that age at menarche is recalled moderately in adulthood. Information on puberty was self-reported, but inaccuracy of data would probably cause non-differential misclassification.

WIDER IMPLICATIONS OF THE FINDINGS

Early maternal age at menarche was associated with earlier pubertal development, and late maternal age at menarche was associated with later pubertal development in both sons and daughters. The largest effect-estimates were for the associations between maternal age at menarche and the daughters' age at menarche and age at breast development.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by the Danish Council for Independent Research (4183-00152). There are no competing interests.

TRIAL REGISTERATION NUMBER

N/A.

Diamond/Porous Titanium Nitride Electrodes With Superior Electrochemical Performance for Neural Interfacing

Robust devices for chronic neural stimulation demand electrode materials which exhibit high charge injection (Q_inj) capacity and long-term stability. Boron-doped diamond (BDD) electrodes have shown promise for neural stimulation applications, but their practical applications remain limited due to the poor charge transfer capability of diamond. In this work, we present an attractive approach to produce BDD electrodes with exceptionally high surface area using porous titanium nitride (TiN) as interlayer template. The TiN deposition parameters were systematically varied to fabricate a range of porous electrodes, which were subsequently coated by a BDD thin-film. The electrodes were investigated by surface analysis methods and electrochemical techniques before and after BDD deposition. Cyclic voltammetry (CV) measurements showed a wide potential window in saline solution (between −1.3 and 1.2 V vs. Ag/AgCl). Electrodes with the highest thickness and porosity exhibited the lowest impedance magnitude and a charge storage capacity (CSC) of 253 mC/cm², which largely exceeds the values previously reported for porous BDD electrodes. Electrodes with relatively thinner and less porous coatings displayed the highest pulsing capacitances (C_pulse), which would be more favorable for stimulation applications. Although BDD/TiN electrodes displayed a higher impedance magnitude and a lower C_pulse as compared to the bare TiN electrodes, the wider potential window likely allows for higher Q_inj without reaching unsafe potentials. The remarkable reduction in the impedance and improvement in the charge transfer capacity, together with the known properties of BDD films, makes this type of coating as an ideal candidate for development of reliable devices for chronic neural interfacing.

Concentration of soluble urokinase plasminogen activator receptor (suPAR) in the pre-ovulatory follicular fluid is associated with development of ovarian hyperstimulation syndrome during ovarian stimulation

PURPOSE

Investigating whether pre-ovulatory follicular fluid (FF) levels of selected proteins differ between women who do or do not develop severe ovarian hyperstimulation syndrome (OHSS) and evaluate whether they potentially could guide a "freeze-all" strategy.

METHODS

FF was collected during a randomized controlled trial comparing OHSS in antagonist versus agonist protocol including 1050 women in their first assisted reproductive technology (ART) cycle during year 2009-2013. The present sub-study is a matched case-control study comparing FF levels of soluble urokinase plasminogen activator receptor (suPAR), C-reactive protein, placental growth factor, vascular endothelial growth factor, and angiopoietins 1 and 2 in OHSS cases (n = 25, severe OHSS, and ≥ 15 oocytes), high-risk controls (n = 25, no OHSS, and ≥ 15 oocytes), and low-risk controls (n = 25, no OHSS, and 5-8 oocytes).

RESULTS

FF level of suPAR differed significantly between the three groups (p = 0.018) with mean (SD) levels of 2.3 (0.4) μg/L, 2.6 (0.8) μg/L, and 2.8 (0.6) μg/L in OHSS cases, high-risk controls, and low-risk controls, respectively. Receiver operating characteristic curve analysis demonstrated that suPAR levels could predict severe OHSS (AUC 0.678; 95% CI 0.553-0.803) with a sensitivity of 64% and a specificity of 66%. None of the other investigated proteins differed between the three groups or between OHSS cases and combined controls.

CONCLUSION

The pre-ovulatory FF level of suPAR was significantly lower in women developing severe OHSS, indicating that the plasminogen activator system could be involved in the pathophysiology of OHSS. However, suPAR did not provide a satisfying predictive value for the prediction of OHSS.

Comparing the effect of strontium-functionalized and fluoride-modified surfaces on early osseointegration

BACKGROUND

Studies have shown that medical devices comprising strontium contribute to bone healing and osseointegration. The aim of this study was to evaluate the in vivo performance of surface-functionalized implants (Ti-Sr-O) showing predictable release characteristics of strontium and compare it to performance a commercially available fluoride-modified surface.

METHODS

Ti-Sr-O functionalized, fluoride-modified,  Grade 4 titanium implants were inserted in the femoral condyle of adult male New Zealand white rabbits. Atomic absorption spectrometry (AAS) was utilized to monitor strontium blood serum levels. Two weeks after insertion, histomorphometric evaluation was performed with respect to bone-to-implant contact (BIC%) and bone formation (BF%) using defined regions of interest.

RESULTS

Mean values for BIC% showed a comparable degree of osseointegration for Ti-Sr-O and the fluoride-modified surface, while BF% revealed a significant difference in increased BF with Ti-Sr-O. AAS measurements did not indicate any influence of the Ti-Sr-O modified implants on the strontium blood serum concentrations.

CONCLUSIONS

Within the limitations of this study, it was shown that the Ti-Sr-O coating, with sustained release characteristics of strontium, enhanced bone apposition and, thus, could find practical applications, e.g., within the field of medical implantology.

Serum Cathepsin H as a Potential Prognostic Marker in Patients with Colorectal Cancer

Cathepsin H is a lysosomal cysteine protease that may participate in tumor progression. In order to evaluate its potential as a prognostic marker, its protein levels were measured by ELISA in preoperative sera from 324 patients with colorectal cancer. The level of cathepsin H was significantly increased in patient sera, the median level was 8.4 ng/mL versus 2.1 ng/mL in 90 healthy blood donors (p<0.0001). A weak association of cathepsin H levels was found with patient age (p=0.02) but not with Dukes’ stage, sex, or the level of carcinoembryonic antigen (CEA). In survival analysis a significant difference was found between the group of patients with low cathepsin H (first tertile) who had a poor prognosis and the remaining patients (p=0.03). The risk of patients was further stratified when cathepsin H levels were combined with CEA. Patients with high CEA and low cathepsin H had the highest risk of death with a hazard ratio of 2.72 (95% CI 1.73–4.28), p<.0001. Our results show that the prognostic information of cathepsin H differs from that of the related cathepsins B and L and suggest different roles during the progression of malignant disease.

It is elemental: soil nutrient stoichiometry drives bacterial diversity

It is well established that resource quantity and elemental stoichiometry play major roles in shaping below and aboveground plant biodiversity, but their importance for shaping microbial diversity in soil remains unclear. Here, we used statistical modeling on a regional database covering 179 locations and six ecosystem types across Scotland to evaluate the roles of total carbon (C), nitrogen (N) and phosphorus (P) availabilities and ratios, together with land use, climate and biotic and abiotic factors, in determining regional scale patterns of soil bacterial diversity. We found that bacterial diversity and composition were primarily driven by variation in soil resource stoichiometry (total C:N:P ratios), itself linked to different land uses, and secondarily driven by other important biodiversity drivers such as climate, soil spatial heterogeneity, soil pH, root influence (plant-soil microbe interactions) and microbial biomass (soil microbe-microbe interactions). In aggregate, these findings provide evidence that nutrient stoichiometry is a strong predictor of bacterial diversity and composition at a regional scale.

Large-scale benchmarking reveals false discoveries and count transformation sensitivity in 16S rRNA gene amplicon data analysis methods used in microbiome studies

BACKGROUND

There is an immense scientific interest in the human microbiome and its effects on human physiology, health, and disease. A common approach for examining bacterial communities is high-throughput sequencing of 16S rRNA gene hypervariable regions, aggregating sequence-similar amplicons into operational taxonomic units (OTUs). Strategies for detecting differential relative abundance of OTUs between sample conditions include classical statistical approaches as well as a plethora of newer methods, many borrowing from the related field of RNA-seq analysis. This effort is complicated by unique data characteristics, including sparsity, sequencing depth variation, and nonconformity of read counts to theoretical distributions, which is often exacerbated by exploratory and/or unbalanced study designs. Here, we assess the robustness of available methods for (1) inference in differential relative abundance analysis and (2) beta-diversity-based sample separation, using a rigorous benchmarking framework based on large clinical 16S microbiome datasets from different sources.

RESULTS

Running more than 380,000 full differential relative abundance tests on real datasets with permuted case/control assignments and in silico-spiked OTUs, we identify large differences in method performance on a range of parameters, including false positive rates, sensitivity to sparsity and case/control balances, and spike-in retrieval rate. In large datasets, methods with the highest false positive rates also tend to have the best detection power. For beta-diversity-based sample separation, we show that library size normalization has very little effect and that the distance metric is the most important factor in terms of separation power.

CONCLUSIONS

Our results, generalizable to datasets from different sequencing platforms, demonstrate how the choice of method considerably affects analysis outcome. Here, we give recommendations for tools that exhibit low false positive rates, have good retrieval power across effect sizes and case/control proportions, and have low sparsity bias. Result output from some commonly used methods should be interpreted with caution. We provide an easily extensible framework for benchmarking of new methods and future microbiome datasets.

Bone regenerating effect of surface-functionalized titanium implants with sustained-release characteristics of strontium in ovariectomized rats

Since strontium (Sr) is known for its anabolic and anticatabolic effect on bone, research has been focused on its potential impact on osseointegration. The objective of this study was to investigate the performance of nanotopographic implants with a Sr-functionalized titanium (Ti) coating (Ti–Sr–O) with respect to osseointegration in osteoporotic bone. The trial was designed to examine the effect of sustained-release characteristics of Sr in poor-quality bone. Three Ti–Sr–O groups, which differed from each other in coating thickness, Sr contents, and Sr release, were examined. These were prepared by a magnetron sputtering process and compared to uncoated grade 4 Ti. Composition, morphology, and mechanical stability of the coatings were analyzed, and Sr release data were gained from in vitro washout experiments. In vivo investigation was carried out in an osteoporotic rat model and analyzed histologically, 6 weeks and 12 weeks after implantation. Median values of bone-to-implant contact and new bone formation after 6 weeks were found to be 84.7% and 54.9% (best performing Sr group) as compared to 65.2% and 23.8% (grade 4 Ti reference), respectively. The 12-week observation period revealed 84.3% and 56.5% (best performing Sr group) and 81.3% and 39.4% (grade 4 Ti reference), respectively, for the same measurements. The increase in new bone formation was found to correlate with the amount of Sr released in vitro. The results indicate that sputtered nanostructured Ti–Sr–O coatings showed sustained release of Sr and accelerate osseointegration even in poor-quality bone, and thus, may have impact on practical applications for medical implants.

Influence of fibrous encapsulation on electro-chemical properties of TiN electrodes

The aim of this study was to investigate how the electrochemical properties of porous titanium nitride stimulation electrode are affected by fibrous encapsulation in vivo. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry and voltage transient (VT) measurements were performed in vivo and in phosphate buffered saline, where the encapsulation process is absent. EIS was used as a non-invasive measurement to follow the inflammation, healing and encapsulation process. EIS showed that the healing and encapsulation process lasted 3-4 weeks. The VTs increased during the first 3-4 weeks, after which they stabilized. The charge storage capacity (CSC) decreased most during the first 3-4 weeks. The increasing VTs and decreasing CSC during the first 3-4 weeks after implantation of the in vivo electrodes seem related to healing and fibrous encapsulation. It is suggested that the charge injection pathway during the encapsulation process changes, which implies that charge injection limits are underestimated with conventional methods.

Influence of implantation on the electrochemical properties of smooth and porous TiN coatings for stimulation electrodes

OBJECTIVE

To determine whether changes in electrochemical properties of porous titanium nitride (TiN) electrodes as a function of time after implantation are different from those of smooth TiN electrodes.

APPROACH

Eight smooth and 8 porous TiN coated electrodes were implanted in 8 rats. Before implantation, voltage transients, cyclic voltammograms and impedance spectra were recorded in phosphate buffered saline (PBS). After implantation, these measurements were done weekly to investigate how smooth and porous electrodes were affected by implantation.

MAIN RESULTS

The electrode capacitance of the porous TiN electrodes decreased more than the capacitance of the smooth electrodes due to acute implantation under fast measurement conditions (such as stimulation pulses). This indicates that protein adhesion presents a greater diffusion limitation for counter-ions for the porous than for the smooth electrodes. The changes in electrochemical properties during the implanted period were similar for smooth and porous TiN electrodes, indicating that cell adhesion poses a similar diffusion limitation for smooth and porous electrodes.

SIGNIFICANCE

This knowledge can be used to optimize the porous structure of the TiN film, so that the effect of protein adhesion on the electrochemical properties is diminished. Alternatively, an additional coating could be applied on the porous TiN that would prevent or minimize protein adhesion.

Microbial diversity and dynamics throughout manufacturing and ripening of surface ripened semi-hard Danish Danbo cheeses investigated by culture-independent techniques

Microbial successions on the surface and in the interior of surface ripened semi-hard Danish Danbo cheeses were investigated by culture-dependent and -independent techniques. Culture-independent detection of microorganisms was obtained by denaturing gradient gel electrophoresis (DGGE) and pyrosequencing, using amplicons of 16S and 26S rRNA genes for prokaryotes and eukaryotes, respectively. With minor exceptions, the results from the culture-independent analyses correlated to the culture-dependent plating results. Even though the predominant microorganisms detected with the two culture-independent techniques correlated, a higher number of genera were detected by pyrosequencing compared to DGGE. Additionally, minor parts of the microbiota, i.e. comprising <10.0% of the operational taxonomic units (OTUs), were detected by pyrosequencing, resulting in more detailed information on the microbial succession. As expected, microbial profiles of the surface and the interior of the cheeses diverged. During cheese production pyrosequencing determined Lactococcus as the dominating genus on cheese surfaces, representing on average 94.7%±2.1% of the OTUs. At day 6 Lactococcus spp. declined to 10.0% of the OTUs, whereas Staphylococcus spp. went from 0.0% during cheese production to 75.5% of the OTUs at smearing. During ripening, i.e. from 4 to 18 weeks, Corynebacterium was the dominant genus on the cheese surface (55.1%±9.8% of the OTUs), with Staphylococcus (17.9%±11.2% of the OTUs) and Brevibacterium (10.4%±8.3% of the OTUs) being the second and third most abundant genera. Other detected bacterial genera included Clostridiisalibacter (5.0%±4.0% of the OTUs), as well as Pseudoclavibacter, Alkalibacterium and Marinilactibacillus, which represented <2% of the OTUs. At smearing, yeast counts were low with Debaryomyces being the dominant genus accounting for 46.5% of the OTUs. During ripening the yeast counts increased significantly with Debaryomyces being the predominant genus, on average accounting for 96.7%±4.1% of the OTUs. The interior of the cheeses was dominated by Lactococcus spp. comprising on average 93.9%±7.8% of the OTUs throughout the cheese processing. The microbial dynamics described at genus level in this study add to a comprehensive understanding of the complex microbiota existing especially on surface ripened semi-hard cheeses.

Electrochemical properties of titanium nitride nerve stimulation electrodes: an in vitro and in vivo study

The in vivo electrochemical behavior of titanium nitride (TiN) nerve stimulation electrodes was compared to their in vitro behavior for a period of 90 days. Ten electrodes were implanted in two Göttingen minipigs. Four of these were used for electrical stimulation and electrochemical measurements. Five electrodes were kept in Ringer's solution at 37.5°C, of which four were used for electrical stimulation and electrochemical measurements. The voltage transients measured in vivo were 13 times greater than in vitro at implantation and they continued to increase with time. The electrochemical properties in vivo and the tissue resistance (R_tissue) followed a similar trend with time. There was no consistent significant difference between the electrochemical properties of the in vivo and in vitro electrodes after the implanted period. The differences between the in vivo and in vitro electrodes during the implanted period show that the evaluation of electrochemical performance of implantable stimulation electrodes cannot be substituted with in vitro measurements. After the implanted period, however, the performance of the in vivo and in vitro electrodes in saline was similar. In addition, the changes observed over time during the post-implantation period regarding the electrochemical properties of the in vivo electrodes and R_tissue were similar, which indicates that these changes are due to the foreign body response to implantation.

A randomized pilot study on single-port versus conventional laparoscopic rectal surgery: effects on postoperative pain and the stress response to surgery

BACKGROUND

Potential benefits of single-port laparoscopic surgery may include improved cosmetic results, less postoperative pain, surgical trauma and faster recovery. Results of randomized prospective studies with a focus on single-port rectal surgery have not yet been presented. The aim of the present study was to compare single-port and conventional laparoscopic surgery for rectal cancer in terms of short-term outcomes including postoperative pain and trauma-induced changes in certain bioactive substances.

METHODS

Patients with non-metastasized rectal cancer were prospectively randomized to single-port (n = 20) or conventional laparoscopic rectal surgery (n = 20). Postoperative pain was assessed at rest, at coughing and during mobilization, with a numeric pain ranking score and was recorded at 6 h after the operation and subsequently every morning daily for 4 days. Levels of C-reactive protein (CRP), interleukin-6 (IL-6) and tissue inhibitor of metalloproteinases-1 (TIMP-1) were determined. Blood samples were collected preoperatively (baseline), and 6, 24, 48, 72 and 96 h after skin incision.

RESULTS

Pain scores were significantly reduced in the single-port group on postoperative days 2, 3 and 4 during coughing and mobilization. In addition, the patients in the single-port group suffered significantly less pain at rest at 6 h after surgery and on postoperative days 1, 3 and 4. The levels of the three markers increased significantly after surgery. The increase was similar between groups for plasma IL-6 and TIMP-1 at all time points, while the CRP levels were significantly lower in the single-port group at 6 (p < 0.001) and 24 h (p < 0.05) after skin incision. Abdominal incisions lengths were significantly shorter in the single-port group (p = 0.001). There was no significant difference between groups in operating time and blood loss, morbidity or mortality rate. The short-term oncological outcome in the two groups was similar.

CONCLUSIONS

Single-port rectal surgery may reduce postoperative pain. Although CRP levels were lower at some time points, results of the present randomized, pilot study suggest that the trauma-induced inflammatory response of single-port operations may be similar to the trauma-induced inflammatory response of conventional laparoscopic surgery.

Enhanced osseointegration of endosseous implants by predictable sustained release properties of strontium

Studies have shown that strontium (Sr) incorporated into surfaces may enhance osseointegration. Thus, we suggested that a sustained Sr release from implant surfaces could improve bone healing. This study verifies and further investigates the effect of a novel Ti-Sr-O functionalized implant surface prepared from a magnetron co-sputtering platform with a continuous release of Sr.

MATERIALS AND METHODS

Four experimental Ti-Sr-O groups, which differed from each other in Sr contents and pre-wash procedures, were tested. Implants were prepared with a Ti-Sr-O coating by means of magnetron co-sputtering and compared to Grade 4 titanium. Composition, morphology and mechanical stability were analyzed; Sr-release data were gained from in vitro washout experiments. In vivo investigations were carried out in a rat model and analyzed histologically regarding bone-to-implant contact and new bone formation 30 days after implantation.

RESULTS

Structural differences were detected between the two basis Ti-Sr-O coatings with 6.7 at.% and 8.9 at.% Sr, respectively. Different release profiles were observed with 8.9 at.% Sr coating exhibiting the highest long-term release of Sr. Median values of new bone formation and bone-to-implant contact was found to be 60.1% and 91.6%, respectively, for the best group compared to 16.6% and 70.6% for the Grade 4 titanium reference. The increase in new bone formation was found to correlate with the amount of Sr released in vitro.

CONCLUSION

The results show that sputtered Ti-Sr-O coatings with sustained release of Sr may improve osseointegration, and could thus have impact on practical applications for medical implants.

Synbiotic Lactobacillus acidophilus NCFM and cellobiose does not affect human gut bacterial diversity but increases abundance of lactobacilli, bifidobacteria and branched-chain fatty acids: a randomized, double-blinded cross-over trial

Probiotics, prebiotics, and combinations thereof, that is synbiotics, have been reported to modulate gut microbiota of humans. In this study, effects of a novel synbiotic on the composition and metabolic activity of human gut microbiota were investigated. Healthy volunteers (n = 18) were enrolled in a double-blinded, randomized, and placebo-controlled cross-over study and received synbiotic [Lactobacillus acidophilus NCFM (10(9) CFU) and cellobiose (5 g)] or placebo daily for 3 weeks. Fecal samples were collected and lactobacilli numbers were quantified by qPCR. Furthermore, 454 tag-encoded amplicon pyrosequencing was used to monitor the effect of synbiotic on the composition of the microbiota. The synbiotic increased levels of Lactobacillus spp. and relative abundances of the genera Bifidobacterium, Collinsella, and Eubacterium while the genus Dialister was decreased (P < 0.05). No other effects were found on microbiota composition. Remarkably, however, the synbiotic increased concentrations of branched-chain fatty acids, measured by gas chromatography, while short-chain fatty acids were not affected.

Prospective study evaluating performance of first-trimester combined screening for trisomy 21 using repeat sampling of maternal serum markers PAPP-A and free β-hCG

OBJECTIVE

To prospectively evaluate the performance of first-trimester combined screening for trisomy 21 using the biochemical markers pregnancy-associated plasma protein-A (PAPP-A) and free beta-human chorionic gonadotropin (free β-hCG) obtained before and at the time of the nuchal translucency (NT) scan.

METHODS

Three fetal medicine departments in Denmark participated in the study. Screening for trisomy 21 was set up as a two-step approach with blood sampling performed before the NT scan (early sample) and again at the time of the NT scan (late sample). PAPP-A and free β-hCG were measured on both the early and late samples. Age-standardized detection and false-positive rates for different screening protocols were calculated.

RESULTS

We collected two blood samples in 27 pregnancies affected by trisomy 21 and in 3891 control pregnancies. The early samples were taken between gestational ages 8 + 0 and 13 + 6 weeks, and the late samples between 11 + 3 and 14 + 6 weeks. The median interval between the samples was 17 (range, 1-40) days. We found a significantly better estimated screening performance when using early sampling vs late sampling (P < 0.05). With a risk cut-off of 1 in 100, at the time of the risk assessment the estimated detection and false-positive rates when using the early sample were 91% (95% CI, 81-98%) and 1.6% (95% CI, 1.3-2.0%), respectively. For fixed false-positive rates the highest detection rates were achieved using both blood samples. When comparing early sampling vs double sampling there was no significant difference in screening performance.

CONCLUSION

In combined first-trimester screening for trisomy 21, use of early sampling with measurement of PAPP-A and free β-hCG before the time of the NT scan can optimize screening performance. Using maternal serum markers obtained both before and at the time of the NT scan has the potential to further improve performance, but larger studies are needed to confirm this potential.

Profiling of the metabolically active community from a production-scale biogas plant by means of high-throughput metatranscriptome sequencing

Structural composition and gene content of a biogas-producing microbial community from a production-scale biogas plant fed with renewable primary products was recently analyzed by means of a metagenome sequencing approach. To determine the transcriptionally active part of the same biogas community and to identify key transcripts for the biogas production process, the metatranscriptome of the microorganisms was sequenced for the first time. The metatranscriptome sequence dataset generated on the Genome Sequencer FLX platform is represented by 484,920 sequence reads. Taxonomic profiling of the active part of the community by classification of 16S ribosomal sequence tags revealed that members of the Euryarchaeota and Firmicutes account for the dominant phyla. Only smaller fractions of the 16S ribosomal sequence tags were assigned to the phyla Bacteroidetes, Actinobacteria and Synergistetes. Among the mRNA-derived sequence tags from the metatranscriptome dataset, transcripts encoding enzymes involved in substrate hydrolysis, acidogenesis, acetate formation and methanogenesis could be identified. Transcripts for enzymes functioning in methanogenesis are among the most abundant mRNA tags indicating that the corresponding pathway is very active in the methanogenic sub-community. As a frame of reference for evaluation of metatranscriptome sequence data, the 16S rDNA-based taxonomic profile of the community was analyzed by means of high-throughput 16S rDNA amplicon sequencing. Processing of the obtained amplicon reads resulted in 18,598 high-quality 16S rDNA sequences covering the V3-V4 hypervariable region of the 16S rRNA gene. Comparison of the taxonomic profiles deduced from 16S rDNA amplicon sequences and the metatranscriptome dataset indicates a high transcriptional activity of archaeal species. Overall, it was shown that the most abundant species dominating the community also contributed the majority of the transcripts. In the future, key transcripts for the biogas production process will provide valuable markers for evaluation of the performance of biogas-producing microbial communities with the objective to optimize the biotechnology of this process.

Strontium and bone nanostructure in normal and ovariectomized rats investigated by scanning small-angle X-ray scattering

The effect of SrCl(2) treatment on bone nanostructure in a rat ovariectomy model was studied using scanning small-angle X-ray scattering (sSAXS). Twelve 6-month-old female Wistar rats were used. Six animals were ovariectomized (+ovx) and six were left intact after sham surgery (-ovx). Six animals, three +ovx and three -ovx, were treated with 4 mmol SrCl(2) (aq)/kg/day (+Sr), whereas the remaining six received placebo (-Sr) for 140 days. Rats were labeled with flourochromes at days 7, 126, and 136. Femoral cross sections were studied using fluorescence microscopy, scanning electron microscopy including energy-dispersive X-ray analysis, and sSAXS. The SAXS data comprised about 5,500 measurements and provided information about mineral crystal thickness and orientation in new and old bone. The newly formed bone contained higher levels of Sr(2+) in +Sr than in -Sr animals, indicating that the Sr(2+) was incorporated into the new bone. Mineral plates were significantly thicker in old bone, 2.62 nm (95% CI 2.58-2.66), than in new bone, 2.41 nm (95% CI 2.36-2.46). Surprisingly, mineral plates in new bone were significantly thicker (2.52 [95% CI 2.47-2.57] nm vs. 2.41 [95% CI 2.36-2.46] nm, P = 0.017) in +ovx rats than in -ovx rats. However, no significant effect of SrCl(2) on mineral plate thicknesses in new bone was observed. The statistical model yielded estimates of the difference in bone mineral plate thickness induced by Sr. The estimated effect of Sr was -0.09 (95% CI -0.21 to 0.03) and 0.02 (95% CI -0.10 to 0.14) nm for new bone in -ovx and +ovx rats, respectively.

Biological variation and reference intervals for circulating osteopontin, osteoprotegerin, total soluble receptor activator of nuclear factor kappa B ligand and high‐sensitivity C‐reactive protein

OBJECTIVE

Monitoring inflammatory diseases and osteoclastogenesis with osteopontin (OPN), osteoprotegerin (OPG), total soluble receptor activator of nuclear factor kappa B ligand (total sRANKL) and high-sensitivity C-reactive protein (hsCRP) has recently attracted increased interest. The purpose of our study was to determine reference intervals, variability caused by sampling time, biological variation and stability after repeated freeze-thaw cycles of circulating levels of OPN, OPG, total sRANKL and hsCRP.

MATERIAL AND METHODS

Plasma OPN and plasma OPG concentrations were determined with sandwich ELISA; serum total sRANKL concentration was determined using a two-site sandwich ELISA; and hsCRP was analysed by turbidimetry in 300 Danish blood donors (183 M and 117 F) with a median age of 43 years (range 18-64 years). Variability due to biological variation and sampling time was studied in serial samples from 38 healthy subjects.

RESULTS

The 95th percentiles in the donors were 76 microg/L for OPN, 4.2 pmol/L for OPG, 40.2 nmol/L for total sRANKL and 12 mg/L for hsCRP. The overall medians for both genders were 51 microg/L, 2.2 pmol/L, 0.66 nmol/L and 1.0 mg/L, respectively. We found a significant correlation between hsCRP and OPN (rho = 0.173; p<0.003). The biological within-subject variations were calculated to be 8.2 % for OPN, 8.8% for total sRANKL and 50% for hsCRP.

CONCLUSIONS

Reference intervals have been established with a high analytic performance for OPN and an acceptable analytic performance for OPG and total sRANKL. The study revealed low biological variation for OPN and total sRANKL and high biological variation for hsCRP.

Effect of syncytiotrophoblast microvillous membrane treatment on gene expression in human umbilical vein endothelial cells

OBJECTIVE

Syncytiotrophoblast membrane fragments (STBM) exist in the peripheral circulation in pregnant women and it has been shown that the level of circulating STBM is significantly increased with pre-eclampsia compared with uncomplicated pregnancies. STBM could be one of the factors which directly causes the endothelial cell dysfunction of pre-eclampsia. This study investigates the effect of STBM on endothelial cell gene expression.

DESIGN

Human umbilical vein endothelial cells were cultured in the presence and absence of STBM. At specified time points, total RNA was purified from the cultures and analysed on microarrays.

SETTING

A laboratory investigation using placentas obtained from a hospital delivery ward.

SAMPLE

Placentas from nine healthy women were obtained. STBM vesicles were isolated from the placentas and umbilical vein endothelial cell cultures were established from the umbilical cords.

METHODS

Gene expression was screened by Affymetrix GeneChips and confirmed with real-time polymerase chain reaction or enzyme-linked immunosorbent assay.

MAIN OUTCOME MEASURES

Fold changes in gene expression levels between treated and control cultures were calculated from the microarray results.

RESULTS

Overall, the results do not show any great changes in gene expression in endothelial cells after STBM treatment (28 genes changed two-fold or more out of approximately 10,000 genes examined by microarray). In general, the changes observed are consistent with inhibition of proliferation of endothelial cells by exposure to STBM. The unfolded protein response in particular may be involved.

CONCLUSIONS

STBM may influence endothelial cell function during pregnancy but STBM alone cannot account for the entire range of endothelial dysfunctions observed in pre-eclampsia.

Real-time absorption and scattering characterization of slab-shaped turbid samples obtained by a combination of angular and spatially resolved measurements

We present a fast and accurate method for real-time determination of the absorption coefficient, the scattering coefficient, and the anisotropy factor of thin turbid samples by using simple continuous-wave noncoherent light sources. The three optical properties are extracted from recordings of angularly resolved transmittance in addition to spatially resolved diffuse reflectance and transmittance. The applied multivariate calibration and prediction techniques are based on multiple polynomial regression in combination with a Newton--Raphson algorithm. The numerical test results based on Monte Carlo simulations showed mean prediction errors of approximately 0.5% for all three optical properties within ranges typical for biological media. Preliminary experimental results are also presented yielding errors of approximately 5%. Thus the presented methods show a substantial potential for simultaneous absorption and scattering characterization of turbid media.

Preanalytical handling of samples for measurement of plasma lactate in HIV patients

Lactic acidosis is a feared side effect of nucleoside analog treatment, one of the cornerstones in the management of HIV infection. Precise and reliable lactate measurements are prerequisites for the diagnosis of hyperlactatemia. The effects of venous stasis, time to measurement and storage temperature on p-lactate levels, p-glucose levels, anion gap and pH were investigated. Ten HIV patients (n=8 on highly active antiretroviral therapy) and 4 healthy control subjects were studied. Blood was drawn without stasis at time 0 and with stasis for 2 and 8 min into heparin-preserved test tubes. The tubes were placed at a room temperature (25 degrees C) and on crushed ice and consecutively monitored for up to 360 min. The mean increases in p-lactate in blood kept in test tubes at 25 degrees C, measured from 0 to 60 min and from 240 to 360 min, were increased in HIV patients compared with controls (0.78 mmol/Lh +/- 0.02 vs. 0.63 mmol/Lh +/- 0.05, (p=0.009) and 0.65 mmol/Lh +/- 0.03 vs. 0.53 mmol/Lh +/- 0.05, (p=0.042)). It was found that placing the tubes on crushed ice rather than keeping them at 25 degrees C controlled glycolysis and lactate production measured over a 6-h period (0.033 mmol/Lh +/- 0.006 vs. 0.32 mmol/Lh +/- 0.01, (p<0.0001) and 0.064 mmol/Lh +/- 0.008 vs. 0.64 mmol/Lh +/- 0.02, (p<0.0001)). The total increases in lactate levels in the test tubes placed on crushed ice for 4 h and in those kept at 25 degrees C for 15 min were comparable (0.28 +/- 0.03 mmol/L vs. 0.20 +/- 0.03). Compared with storage at 25 degrees C, keeping the test tubes on crushed ice also preserved pH and anion gap over a 6-h measurement period (pH: 0.026 +/- 0.004 vs. 0.12 +/- 0.01 and anion gap: -0.8 +/- 0.4 mmol/L vs. 4.1 +/- 0.4). Two minutes of venous stasis had no influence on p-lactate levels (0.02 +/- 0.04 mmol/L, p=0.70), whereas 8 min of stasis increased p-lactate levels by 0.11 +/- 0.04 mmol/L, p=0.009. It is concluded that major errors in measurements of p-lactate, anion gap and pH can be prevented by placing test tubes on crushed ice for up to 4 h until measurement.

Tele-monitoring of home blood pressure in treated hypertensive patients

AIM

To compare the accuracy of clinic blood pressure (CBP) and telemedical home blood pressure (HBP) measurement in the assessment of antihypertensive effect.

METHODS

362 patients on antihypertensive medication performed HBP measurement (5 days, duplicate measurements, four times daily) and ambulatory blood pressure (ABP) monitoring in random order. Main outcome measure was the agreement of CBP and HBP with daytime ABP.

RESULTS

CBP was much higher than ABP and average HBP (p < 0.001). There was a progressive decline in HBP over the course of the study, achieving the level of daytime ABP on the last 2 monitoring days. The correlation between CBP and ABP was weak (systolic: r = 0.343, diastolic r = 0.430), whereas strong correlations existed between HBP and ABP (systolic r = 0.804, diastolic r = 0.776). A progressive improvement in the strength of the correlation between average HBP of single days and ABP was obtained over the 5 monitoring days. The HBP readings taken in the afternoon showed a stronger correlation with ABP than the values measured in the morning, at noon and in the evening. Averaging more HBP readings taken on succeeding days resulted in a progressive improvement in the agreement with ABP with a further benefit when readings of day 1 were included.

CONCLUSIONS

The accuracy of telemedical HBP measurement is substantially better than that of CBP. The results suggest, that HBP should be measured for 5 days, and afternoon measurements should be preferred in assessing control of hypertension.

Accuracy of telemedical home blood pressure measurement in the diagnosis of hypertension

This study was conducted to compare the accuracy of clinic blood pressure (CBP) and telemedical home blood pressure (HBP) measurement in the diagnosis of hypertension in primary care. The study subjects were 411 patients with average CBP > or =140 mmHg systolic or > or =90 mmHg diastolic, who performed telemedical HBP measurement (5 days, four times daily) and ambulatory blood pressure (ABP) monitoring in random order. Main outcome measure was the agreement of CBP and HBP with daytime ABP. CBP was much higher than daytime ABP and average HBP (P<0.001) with no difference between the latter two. The correlation between CBP and ABP was weak (systolic: r=0.499, diastolic: r=0.543), whereas strong correlations existed between HBP and ABP (systolic: r=0.847, diastolic: r=0.812). A progressive improvement in the strength of the linear regression between average HBP of single days and ABP was obtained from day 1 to day 4, with no further benefit obtained on the fifth day. The HBP readings taken at noon and in the afternoon showed significantly stronger correlations with ABP than the blood pressures measured in the morning and in the evening. In conclusion, the accuracy of telemedical HBP measurement was substantially better than that of CBP in the diagnosis of hypertension in primary care. HBP most accurately reflected ABP on the fourth day of monitoring, and the readings at noon and in the afternoon seemed to be most accurate.

Expression of nitric oxide synthases and effects of L-arginine and L-NMMA on nitric oxide production and fluid transport in collagenous colitis

BACKGROUND AND AIMS

Luminal nitric oxide (NO) is greatly increased in the colon of patients with collagenous and ulcerative colitis. To define the source and consequence of enhanced NO production we have studied expression of NO synthase (NOS) isoforms and nitrotyrosine in mucosal biopsies from these patients. In addition, effects on colonic fluid transfer caused by manipulating the substrate of NOS were studied in patients with collagenous colitis.

PATIENTS

Eight patients with collagenous colitis, nine with active ulcerative colitis, and 10 with uninflamed bowel were included.

METHODS

Expression of NOS isoforms was quantified by western blotting. Inducible NOS (iNOS) and nitrotyrosine were localised by immunohistochemistry. Modulation of NOS activity by topical N(G)-monomethyl-L-arginine (L-NMMA) or L-arginine was assessed during perfusion of whole colon. Plasma and perfusate nitrite/nitrate (NOx) was measured by Griess' reaction.

RESULTS

Both in collagenous and ulcerative colitis, expression of iNOS was 10(2)-10(3) higher (p<0.001) than in uninflamed bowel and localised primarily to the epithelium. Endothelial NOS was evenly expressed in all groups while neuronal NOS was undetectable. Nitrotyrosine was markedly expressed in active ulcerative colitis but rarely detected in collagenous colitis and never in uninflamed bowel. In collagenous colitis, the output of NOx was markedly increased compared with uninflamed bowel (283 (58) v <37 nmol/min; p<0.01) and fluid was net secreted. L-NMMA reduced the output of NOx by 13-66% (95% confidence intervals) and secretion of fluid by 25-109% whereas L-arginine increased the output of NOx by 3-39% and secretion of fluid by 15-93%.

CONCLUSIONS

In collagenous colitis, as opposed to ulcerative colitis, upregulation of iNOS occurs in the absence of nitrotyrosine formation and mucosal damage. Excess generation of NO may be the primary cause of diarrhoea in this condition.

zeta-, epsilon-, and gamma-Globin mRNA in blood samples and CD71(+) cell fractions from fetuses and from pregnant and nonpregnant women, with special attention to identification of fetal erythroblasts

BACKGROUND

Information about the appearance of gamma-, epsilon-, and zeta-globin mRNAs in fetal erythroblasts during gestation and about the presence and amounts of these mRNAs in pregnant and nonpregnant women is important from the perspective of using these molecules as a marker of fetal erythroblasts. A specific marker is necessary for isolation and identification of fetal nucleated red blood cells from maternal blood samples for use in antenatal diagnosis of fetal genetic or chromosomal abnormalities.

METHODS

We used a very sensitive reverse transcription-PCR (RT-PCR) method, coamplification analysis of gamma- and epsilon-globin cDNA, and quantitative analysis of gamma-globin mRNA based on competitive RT-PCR to investigate these aspects.

RESULTS

All adult whole-blood samples were negative for epsilon- and zeta-globin mRNA. Analyses of CD71(+) cell fractions showed that specimens from 19 of 20 nonpregnant and 10 of 14 pregnant women (at 9-13 weeks of gestation) were positive for gamma-globin mRNA (Fisher's exact test, P = 0.13), and those from 3 of 20 nonpregnant and 5 of 14 pregnant women were positive for zeta-globin mRNA (Fisher's exact test, P = 0.23). No epsilon-globin mRNA was detected in CD71(+) cell fractions from 1-mL blood samples from adults. CD71(+) cell fractions from eight fetal blood samples (at 17-20 weeks of gestation) were positive for all three globin mRNAs. We found no statistically significant difference between the amounts of gamma-globin mRNA in pregnant and nonpregnant women.

CONCLUSIONS

This study indicates that epsilon-globin mRNA might function as a marker for fetal CD71(+) cells early in pregnancy. Although gamma-globin mRNA can be detected in CD71(+) cell fractions from most adults, these transcripts also may be of use because of a marked difference between adult and fetal values.

Increased levels of specific leukocyte- and platelet-derived substances during normal anti-tetanus antibody synthesis in patients with inactive Crohn disease

BACKGROUND

Crohn disease is considered a consequence of inappropriate upregulation of immune reactions evoked by the intestinal microflora or luminal antigens. Since the intestinal mucosa is continuously exposed to tetanus toxoid we studied the antibody response to tetanus toxoid booster immunization in patients with Crohn disease and the subsequent release of various inflammatory mediators and growth factors in blood.

METHODS

Ten patients with inactive disease and no concurrent medication and 12 age-and gender-matched healthy volunteers with anti-tetanus antibody levels less than 0.1 IU/ml were inoculated with 1 ml (6 Lf units) of tetanus toxoid vaccine. The anti-tetanus antibody levels were determined in serum obtained before inoculation and after 7, 14 and 28 days, respectively. C-reactive protein (CRP), interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha), histamine, vascular endothelial growth factor (VEGF), tissue inhibitor of metalloproteinases-1 (TIMP-1), plasminogen activator inhibitor type-1 (PAI-1) and myeloperoxidase (MPO) were determined in serum or plasma obtained on the same days.

RESULTS

After inoculation anti-tetanus antibody levels were equally raised in patients and healthy volunteers. Pre-inoculation CRP levels were below the upper level of the normal range (<10 mg/l) in all inoculated patients/volunteers. No differences in IL-6, TNF-alpha, MPO or histamine levels between patients and healthy volunteers were observed. CRP levels were within the normal range and IL-6, TNF-alpha, MPO and histamine levels were unchanged in patients and volunteers during the study period. The levels of VEGF, TIMP-1 and PAI-1 were unchanged in the healthy volunteers during the study period, but were significantly (P < 0.05) increased at day 14 in patients with Crohn disease. At day 28 the levels had fallen to pre-inoculation levels, apart from PAI-1, which was still significantly (P<0.05) increased.

CONCLUSIONS

In patients with inactive Crohn disease, booster immunization against tetanus toxoid seems to result in normal anti-tetanus antibody synthesis, but it may cause inappropriate release of certain bioactive substances, which are known to play a major role in modulation of the inflammatory response.

Serial measurements of serum human placental lactogen (hPL) and serial ultrasound examinations in the evaluation of fetal growth

Serial serum hPL measurements and serial ultrasound fetometry were compared in the evaluation of fetal growth by relating these two parameters to size at birth and to clinical factors known to influence size at birth. The data were from a prospective study of 1000 consecutive pregnant women considered to be at risk for fetal growth retardation with retrospective analysis. Serum hPL was measured by radioimmunoassay and fetal weight estimated by ultrasound every 3 weeks during the last trimester. hPL values were expressed as multiples of the median (MoM) and linear regression analysis of the hPL MoM values was carried out for each pregnancy to find the slope of the line (hPL-slope); at least 3 serum hPL values were required. The estimated fetal weight and weight-for-age at birth was expressed in Z-scores. The individual intrauterine growth velocity was calculated by regression analysis and expressed as change in Z-score for 12 weeks. At least two ultrasound measurements over an interval of at least 42 days were used to estimate the fetal growth velocity. In 588 women the file was complete. The main outcome measures were the individual mean hPL, hPL-slope, fetal growth velocity, birth weight deviation, smoking in pregnancy and diagnosis of preeclampsia. A significant correlation was found between the hPL-slope and the intrauterine fetal growth velocity (r=0.34), and between hPL-slope and birth weight deviation (r=0.32). Mean hPL was correlated to birth weight deviation (r=0.27), but only very weakly to intrauterine growth velocity (r=0.08). hPL-slope and intrauterine growth velocity independently predicted birth weight deviation. Heavy smoking which was stopped before the third trimester was not associated with low intrauterine growth velocity, but with a low hPL-slope. Preeclampsia was associated with a trend towards low and decreasing hPL and with an increasing intrauterine growth velocity and birth weight deviation. In conclusion the rate of change of serial hPL measurements correlated well to intrauterine fetal growth velocity in the third trimester as estimated by ultrasound and to the deviation in birth weight, but hPL seems to have a separate physiological significance, since it did not pick up when smoking was stopped and growth velocity was normalised and it did not at all detect the increased growth associated with preeclampsia.

Preoperative plasma plasminogen activator inhibitor type-1 and serum C-reactive protein levels in patients with colorectal cancer. The RANX05 Colorectal Cancer Study Group

BACKGROUND

Preoperative plasma plasminogen activator inhibitor-1 (PAI-1) is a prognostic variable in patients with colorectal cancer. It has been suggested, however, that plasma PAI-1 is a nonspecific prognostic parameter similar to the acute-phase reactant C-reactive protein (CRP). In the present study we analyzed the association between plasma PAI-1 and serum CRP in patients scheduled for elective resection of colorectal cancer. In addition, the prognostic value of PAI-1 and CRP was studied in this patient cohort.

METHODS

PAI-1 and CRP were analyzed in citrated plasma and serum, respectively, obtained preoperatively from 594 patients. Patients who required preoperative blood transfusion received SAGM blood, in which soluble PAI-1 is not present. None of the patients received pre- or postoperative adjuvant chemotherapy, and all were followed in the outpatient clinic for at least 5 years or until death. The association of PAI-1 and CRP, respectively, with survival was tested using the median value of PAI-1 and the upper normal limit for CRP. Analyses were performed by inclusion of all patients, and in the subgroup of patients, who underwent curative resection.

RESULTS

The median follow-up period was 6.8 (5.4-7.9) years. The median value of plasma PAI-1 was 35.8 ng/ml, and values greater than 94 nmol/L identified patients with increased CRP levels. Comparison of the molecules showed that PAI-1 was weakly correlated with CRP (r = .26; P <.0001). Both molecules showed a Dukes independent distribution. In univariate survival analyses high levels of PAI-1 were found associated with poor prognosis and low levels with good prognosis (P = .02, HR: 1.3). Similarly, high levels of CRP were found associated with poor prognosis and low levels with good prognosis (P <.0001, HR: 1.9). In a multivariate statistical analysis including Dukes classification, gender, age, tumor location, perioperative blood transfusion, PAI-1 and CRP, plasma PAI-1 was a dependent prognostic variable, while serum CRP (P <.0001; HR: 1.4; 95% CI: 1.3-1.5) was found to be a Dukes independent prognostic variable. Similar analyses, excluding patients with Dukes' D disease showed serum CRP to be an independent prognostic variable (P <.0001; HR: 1.3: 95% CI: 1.2-1.5).

CONCLUSIONS

This study did not show a strong correlation between plasma PAI-1 and serum CRP in patients with colorectal cancer. Serum CRP was found to be a Dukes independent prognostic variable in this patient cohort, and was found to identify a subgroup of curatively resected patients at risk for short survival.

Supercritical fluid chromatography as a method of analysis for the determination of 4-hydroxybenzylglucosinolate degradation products

In the present study analytical and preparative supercritical fluid chromatography (SFC) were used for investigation of myrosinase catalysed degradation of 4-hydroxybenzylglucosinolate (sinalbin). Sinalbin occurs as a major glucosinolate in seeds of Sinapis alba L., in various mustards and other food products. The degradation products were identified and quantified by analysis based on a developed SFC method using a bare silica column. Determinations comprised transformation products of sinalbin, produced both during degradation of isolated sinalbin, and during autolysis of meal from S. alba seeds. The conditions in the developed SFC method were used as basis for the preparative SFC procedure applied for isolation of the components prior to their identification by nuclear magnetic resonance (NMR) spectroscopy. Myrosinase catalysed sinalbin hydrolysis resulted in the reactive 4-hydroxybenzyl isothiocyanate as an initial product at pH values from 3.5 to 7.5 whereas 4-hydroxybenzyl cyanide was one of the major products at low pH values. 4-Hydroxybenzyl isothiocyanate was found to disappear from the aqueous reaction mixtures in a few hours, as it reacted easily with available nucleophilic reagents. 4-Hydroxybenzyl alcohol was found as the product from reaction with water, and with ascorbic acid, 4-hydroxybenzylascorbigen was produced.

Supercritical fluid chromatography as basis for identification and quantitative determination of indol-3-ylmethyl oligomers and ascorbigens

Indol-3-ylmethylglucosinolate (glucobrassicin) occurs in most plants of the Brassicaceae family together with hydroxy and methoxy derivatives of glucobrassicin. These compounds and products produced therefrom have been the subject of considerable research interest due to their potential anticarcinogenic effects, and thereby a need for techniques to work with the individual compounds. A method using normal-phase supercritical fluid chromatography (SFC) with methanol as modifier has been developed for determination and quantification of the various indol-3-ylmethyl derivatives including ascorbigens formed from the glucobrassicin degradation product, indol-3-ylmethanol, under acidic conditions (pH 2-6) with and without the presence of ascorbic acid. The SFC method had detection limits in the 10-100-pmol range. In the absence of ascorbic acid a range of oligomers were formed, whereas the presence of ascorbic acid favoured the formation of ascorbigen and products thereof. Quantitatively important indol-3-ylmethyl oligomers consisting of up to five indol rings have been purified with preparative SFC and identified from MS and 1D and 2D NMR experiments with complete assignment of chemical shifts to all of the atoms. Investigation of the autolysis products of white cabbage showed that ascorbigens were the quantitatively dominating degradation products of indol-3-ylmethylglucosinolates.

Determination of ascorbigens in autolysates of various Brassica species using supercritical fluid chromatography

A new method of analysis based on normal phase supercritical fluid chromatography (SFC) has been developed for investigation of ascorbigens [2-C-(indol-3-ylmethyl)-beta-L-xylo-3-hexulofuranosonic acid gamma-lactone derivatives]. This method has been adapted to preparative isolation and quantitative determinations of individual ascorbigens comprising ascorbigen, neoascorbigen, and 4-methoxyascorbigen. The structures of these compounds have been revealed from 1D ((1)H, (13)C) and 2D (COSY, HMQC, HMBC) NMR experiments. The developed SFC method had an acceptable linearity for the ascorbigens with correlation coefficients (R(2)) > 0.9995 (n = 10) in the range of 0.13-4.9 nmol injected, detection limits were below 13 pmol, retention time stabilities were excellent, and relative response factors have been determined. The SFC method has been used for determination of ascorbigens produced during autolysis of indol-3-ylmethylglucosinolates in various Brassica vegetables and rapeseed seedlings. Generally, 30-60% of the indol-3-ylmethylglucosinolates in the plants were transformed into ascorbigens, with the concentration in autolysates varying from 0.51 +/- 0.002 to 3.72 +/- 0.21 micromol/g of dry weight (DW) for ascorbigen, from 0.05 +/- 0.01 to 2.42 +/- 0.23 micromol/g of DW for neoascorbigen, and from 0.03 +/- 0.002 to 0.84 +/- 0.07 micromol/g of DW for 4-methoxyascorbigen.

Subcellular distribution of urokinase and urokinase receptor in human neutrophils determined by immunoelectron microscopy

A high-affinity receptor for urokinase-type plasminogen activator (uPAR) has been identified on the plasma membrane of a number of different cell types, and has been shown to be important for plasminogen activation, cell adhesion, and possibly signal transduction. uPAR and uPA cosediment with secretory vesicles and specific granules by subcellular fractionation and translocate to the plasma membrane upon activation of neutrophils. Here the subcellular distribution of uPAR and uPA is studied by electron microscopy of neutrophils using immunogold double labeling for uPAR and uPA and a set of markers for well-defined subtypes of granules: matrix metalloproteinase type-9 (MMP-9) for gelatinase granules, lactoferrin (LF) for specific granules, and myeloperoxidase (MPO) and neutrophil elastase (NE) for primary granules. With this technique uPAR colocalizes with uPA in 71% of labeled granules. In granules containing uPAR the degree of coexpression with MMP-9, MPO and NE was 19, 66, and 74%, respectively. In granules labeled for uPA the corresponding overlap with MMP-9, MPO and NE was 24, 64, and 51%, respectively. Low levels of co-localization were found for uPAR and LF (7%) and for uPA and lactoferrin (5%). The results indicate that uPAR and uPA are present in gelatinase granules and primary granules, but rarely in specific granules. The demonstration of uPAR and uPA in primary granules is of particular interest, and may indicate that uPAR and uPA participate in the activation of latent hepatocyte growth factor of neutrophils.

Polymorphism in the regulatory region located more than 1.1 kilobases 5' to the start site of transcription, the promoter region, and exon 1 of the HLA-G gene

The non-classic Human Leucocyte Antigen class Ib molecule, HLA-G, is expressed on the invasive, extra-villous cytotrophoblast in human placenta. HLA-G protects against natural killer (NK)-cell-mediated lysis and may modulate the secretion of cytokines. Aberrant expression of HLA-G has been reported in certain disorders of pregnancy. We have studied the DNA sequences of the putative regulatory region located more than 1.1 kilobases 5' from the start site of transcription (a 244 bp HindIII/EcoRI fragment) of the HLA-G gene and of the promoter region to detect any possible polymorphism. We detected one nucleotide substitution in the HindIII/ EcoRI region and one in the promoter region in the alleles G*01012, G*01013, G*0104, and G*0105N compared to G*01011. Several nucleotide substitutions were detected in the region between the 1.1 kb 5' regulatory region and the promoter region. Alleles can be divided into two groups based on the detected polymorphism. The nucleotide substitutions may have implications for the binding of nuclear factors to the regulatory regions. To our knowledge this is the first study of any polymorphism in the 5'-flanking sequences to the HLA-G gene. Further studies are needed to elucidate the exact impact of the detected polymorphism on levels or developmental regulation of HLA-G expression.

Plasma urokinase receptor levels in patients with colorectal cancer: relationship to prognosis

BACKGROUND

The proteolytic enzyme plasmin, which is generated from the precursor plasminogen by the action of urokinase plasminogen activator, is thought to play a role in tumor cell invasion and metastasis. Urokinase plasminogen activator receptor (uPAR) is functionally involved in the cell surface activation (i.e., cleavage) of plasminogen. Increased tumor tissue levels of uPAR are associated with poor prognosis in several types of cancer. This retrospective study was undertaken to test the relationship between preoperative plasma levels of soluble uPAR (suPAR) and survival in patients with colorectal cancer.

METHODS

suPAR levels in preoperative plasma from 591 patients with colorectal cancer were determined by use of a kinetic enzyme-linked immunosorbent assay and analyzed with respect to associations with postoperative survival, Dukes' stage, age, and serum carcinoembryonic antigen level. Plasma suPAR measurements were log transformed for survival analysis, which employed the Kaplan-Meier method and the Cox proportional hazards model. All P values reported are two-sided.

RESULTS

Univariate analysis, using the log-transformed suPAR concentrations, demonstrated that there was an increasing risk of mortality with increasing plasma suPAR level (P<.0001). An arbitrary cut point, the median for all patients (1.37 ng/mL), divided patients with Dukes' stage B, C, or D disease into statistically different prognostic groups. In multivariate Cox analysis including Dukes' stage, age, and carcinoembryonic antigen level, the suPAR concentration independently predicted survival (P<.0001).

CONCLUSIONS

The preoperative plasma suPAR level independently predicted survival of patients with colorectal cancer. Further studies of plasma suPAR in patients with cancer are needed to evaluate the utility of plasma suPAR measurements and cut points in identifying high-risk patients among those with early stage disease.