Effect of CYP2D6 and CYP2C19 genotypes on atomoxetine serum levels: A study based on therapeutic drug monitoring data

AIMS

Atomoxetine is mainly metabolized by CYP2D6 while CYP2C19 plays a secondary role. It is known that patients carrying genotypes encoding decreased/absent CYP2D6 metabolism obtain higher atomoxetine concentrations and are at increased risk of adverse effects. Here, we aimed to investigate the added effects of reduced-function CYP2C19 genotype on atomoxetine concentrations in real-world settings.

METHODS

Serum atomoxetine concentrations and CYP2D6/2C19 genotypes were included from a therapeutic drug monitoring service. Patients were first subgrouped according to CYP2D6 encoding normal, reduced or absent CYP2D6 metabolism, referred to as normal (NM), intermediate (IM) or poor metabolizers (PM). Then, the effect of reduced-function CYP2C19 genotypes was investigated. Genotyping of the CYP2D6 nonfunctional or reduced variant alleles comprised CYP2D6*3-*6, *9-*10 and *41. For CYP2C19, the CYP2C19*2 was analysed to define metabolizer phenotype. Dose-adjusted serum atomoxetine concentration was the exposure measure.

RESULTS

Using a patient cohort (n = 315), it was found that CYP2D6 IM and PM patients had 1.9-fold (95% confidence interval: 1.4-2.7) and 9.6-fold (5.9-16) higher exposure of atomoxetine compared with CYP2D6 NMs. CYP2C19*2 carriers had 1.5-fold (1.1-2.2) higher atomoxetine exposure than noncarriers regardless of CYP2D6 genotype.

CONCLUSION

CYP2D6 genotype has a great impact on atomoxetine exposure, where our real-world data suggest atomoxetine dose requirements to be around half and 1/10 in CYP2D6 IM and PM vs. NM patients, respectively. When adding CYP2C19 genotype as a factor of relevance for personalized atomoxetine dosing, CYP2C19*2 carriers should further reduce the dose by a third. These findings suggest that pre-emptive CYP2D6/CYP2C19 genotyping should be performed to individualize atomoxetine dosing and prevent adverse effects.

Expression of truncated bile salt-dependent lipase variant in pancreatic pre-neoplastic lesions

Pancreatic adenocarcinoma (PDAC) is a dismal disease. The lack of specific symptoms still leads to a delay in diagnosis followed by death within months for most patients. Exon 11 of the bile salt-dependent lipase (BSDL) gene encoding variable number of tandem repeated (VNTR) sequences has been involved in pancreatic pathologies. We hypothesized that BSDL VNTR sequences may be mutated in PDAC. The amplification of BSDL VNTR from RNA extracted from pancreatic SOJ-6 cells allowed us to identify a BSDL amplicon in which a cytosine residue is inserted in a VNTR sequence. This insertion gives rise to a premature stop codon, resulting in a truncated protein and to a modification of the C-terminal amino-acid sequence; that is PRAAHG instead of PAVIRF. We produced antibodies directed against these sequences and examined pancreatic tissues from patients with PDAC and PanIN. Albeit all tissues were positive to anti-PAVIRF antibodies, 72.2% of patient tissues gave positive reaction with anti-PRAAHG antibodies, particularly in dysplastic areas of the tumor. Neoplastic cells with ductal differentiation were not reactive to anti-PRAAHG antibodies. Some 70% of PanIN tissues were also reactive to anti-PRAAHG antibodies, suggesting that the C insertion occurs early during pancreatic carcinogenesis. Data suggest that anti-PRAAHG antibodies were uniquely reactive with a short isoform of BSDL specifically expressed in pre-neoplastic lesions of the pancreas. The detection of truncated BSDL reactive to antibodies against the PRAAHG C-terminal sequence in pancreatic juice or in pancreatic biopsies may be a new tool in the early diagnosis of PDAC.

Transrectal drainage of pelvic collections: Experience of a single center

BACKGROUND AND OBJECTIVE

Pelvic abscesses are a well-known complication of intestinal diseases or abdominal surgery. We report our case series concerning transrectal drainage by endoscopic ultrasound (EUS).

METHODS

Between January 2010 and august 2014, seven patients received transrectal drainage by endoscopic ultrasound (EUS) were selected and analyzed.

RESULTS

Two pigtails was positioned under fluoroscopic and EUS control. The success rate was 100% and complication rate was 0%. The median time of hospitalization was 10 days [range 4-25].

CONCLUSIONS

The technique appears to be safe and feasible in all etiologies. In our experience, we can considerate transrectal drainage by EUS like a first-line technique in experienced hands.

Characteristics of methadone-related fatalities in Norway

There are currently over 7000 patients enrolled in opioid maintenance treatment (OMT) programs in Norway. A rise in methadone-related deaths proportional to increasing methadone sales over the period 2000-2006 has been observed, but the causative factors for these fatalities have been elusive. In the present study, individual characteristics, methadone concentrations and additional toxicological findings were analyzed. Methadone intoxication deaths (n = 264) were divided into 3 groups according to toxicological findings in whole blood: group 1 - methadone detected alone, or together with one additional drug at low or therapeutic levels, or a low concentration of ethanol (<1 g/L) (n = 21); group 2 - multiple additional drugs/substances detected below lethal levels (n = 175); group 3 - one or more additional drugs/substances detected at lethal levels, or ethanol >3 g/L (n = 55). Methadone blood concentrations in decedents who had been enrolled in OMT were higher than for decedents not in treatment, in all groups. Blood methadone concentrations around 1 mg/L were present in fatal multi-drug intoxications in OMT patients. Results suggest that some patients may be at risk of dying when combining therapeutic concentrations of methadone with other psychoactive substances. Somatic disease was a common finding among deceased OMT patients. Concentrations in methadone users not enrolled in OMT were predominantly between 0.3 and 0.4 mg/L and were not related to the presence of other drugs. However, methadone concentrations below 0.1 mg/L may be associated with intoxication following methadone use, both alone and in combination with other drugs. Younger male users (mean age 34 years) seemed to have a higher susceptibility to methadone intoxication.

Percutaneous hepatic radiofrequency for hepatocellular carcinoma: results and outcome of 46 patients

Radiofrequency ablation (RFA) is a curative option for hepatocellular carcinoma (HCC), the most common primary malignancy of the liver. This bicentric retrospective study includes 46 patients admitted for their first percutaneous RFA for HCC. Sixty-three nodules were treated, with an average size of 32.5 mm. Our study confirms the efficiency of this technique for attaining necrosis of HCC nodules, with few complications. Subgroup studies according to RFA mode (mono- or multipolar), etiology of cirrhosis (alcoholic or viral), and HCC size showed better efficiency for multipolar RFA when applied to small tumors and better survival when the cirrhosis was due to viral infection. However, we noted a high rate of local recurrence in our and other recent works compared to previous studies, probably due to improved imaging techniques. The main problem is still de novo intrahepatic recurrence in diseased livers.

Methadone-related deaths in Norway

INTRODUCTION

The use of methadone in opioid maintenance treatment (OMT) is potentially associated with a number of adverse effects and the risk of fatal toxicity. Increased methadone availability may lead to an increase in methadone-related deaths. We have investigated methadone-related deaths in Norway over the period 2000-2006.

MATERIALS AND METHODS

Methadone-positive samples over the period 2000-2006 were identified from forensic toxicological investigations, and demographic and toxicological data were retrieved. The cases were cross-linked with the Norwegian Cause of Death Registry and regional OMT registers.

RESULTS

A total of 312 individuals had died after taking methadone over the period 2000-2006, predominantly men with a mean age of 36. In 85% of cases (n=264), the deceased had died of a methadone-related intoxication, most often in combination with other drugs, including benzodiazepines, cannabis and other opioids. Only 22% of the deceased had been in OMT at the time of death. A larger proportion of OMT patients had died of causes other than intoxications compared to those not in OMT (30% vs. 8%, respectively), most commonly related to disease.

CONCLUSIONS

One methadone-related death occurred, on average, every week over the time period investigated. Only 22% of the deceased were registered in opioid maintenance treatment (OMT) programs. The findings underline the need to control diversion of medication from OMT programs.

Targeting a novel onco-glycoprotein antigen at tumoral pancreatic cell surface by mAb16D10 induces cell death

The mAb16D10 was raised against a pathological onco-glycoform of bile salt-dependent lipase isolated from the pancreatic juice of a patient suffering from a pancreatic adenocarcinoma. We previously showed that mAb16D10 specifically discriminates human pancreatic tumor tissues from other cancer and nontumor tissues. In this study, we report that mAb16D10 inhibited the proliferation of only human pancreatic tumor cells expressing 16D10 plasma membrane Ag. Interaction of mAb16D10 with its cognate surface Ag on pancreatic cells promoted cell death by activation of the p53- and caspase-dependent apoptotic pathway, and silencing of p53 decreased cell death. The decreased proliferation was also partly due to cell cycle arrest in G1/S phase, mAb16D10 triggering of glycogen synthase kinase-3β (GSK-3β) activation, degradation of β-catenin, and decreased expression of cyclin D1. GSK-3β positively affected p53 expression in pancreatic tumor cells after mAb16D10 binding. Inhibition of GSK-3β activity reversed the effects induced by mAb16D10 in SOJ-6 cells, supporting the pivotal role of GSK-3β signaling in the mechanisms of action induced by mAb16D10. Also, mAb16D10 cell treatment led to membrane overexpression of E-cadherin. Both E-cadherin and tumor Ag were localized in membrane lipid cholesterol-rich microdomains and are thought to belong to signaling platforms involved in the induction of cell cycle arrest and cell death. Overall, this study reveals that mAb16D10 holds great potential to prevent pancreatic tumor proliferation by apoptotic cell death, thus promising therapeutic prospects for treatment of pancreatic adenocarcinoma, a highly lethal disease.

Individual psychomotor impairment in relation to zopiclone and ethanol concentrations in blood--a randomized controlled double-blinded trial

AIMS

To investigate individual traffic-relevant impairment related to measured blood zopiclone and ethanol concentrations. Also, we aimed to study possible development of acute tolerance.

DESIGN

A randomized controlled four-way cross-over double-blind trial. Study drugs were zopiclone 5 or 10 mg, 50 g ethanol or placebo.

SETTING

Laboratory study with computerized tests: Connor's Continuous Performance test, Choice Reaction Time and Stockings of Cambridge. Altogether, the tests consisted of 15 test components, representing three levels of behaviour (automotive, control, executive planning), relevant to traffic safety.

PARTICIPANTS

Sixteen healthy male volunteers.

MEASUREMENTS

Each study day, 10 blood samples were collected from each volunteer. Fifteen psychomotor test components were registered at baseline and a further three times after intake. Impairment was defined as any individual deterioration in performance compared to individual baseline performance.

FINDINGS

Blood drug concentrations up to 74 µg/l zopiclone and 0.100% ethanol were measured. We found a clear positive concentration-effect relationship for zopiclone and ethanol for both automotive and control behaviours, and a modest relationship for executive planning behaviour. Significant impairment started to be observed at concentrations above 16 µg/l zopiclone (automotive and control behaviour) and above 0.026% ethanol (automotive behaviour). Acute tolerance was found for both drugs.

CONCLUSIONS

The hypnotic, zopiclone, can impair psychomotor performance at blood concentrations as low as 16 µg/l.

Likelihood ratio-based quality control for nuchal translucency measurements at 11-14 weeks of gestation

OBJECTIVE

To develop a quantitative quality control process of nuchal translucency (NT) measurement at 11-14 weeks of gestation based on the mixture model, characterized by analysis of the corresponding distribution of the likelihood ratio (LR).

METHODS

Based on the published mixture model for NT measurement in the first trimester, we simulated the expected distribution of NT and the corresponding LR. This approach was then tested for the quality control of 15 048 NT measurements performed by four operators trained and certified by The Fetal Medicine Foundation. The new quality control approach based on LR was compared with existing processes based on NT plots, multiples of the median (MoMs) and analysis of the 95(th) centile.

RESULTS

Each operator contributed 2176-4730 examinations. Median, 5(th) and 95(th) centile of NT values ranged from 1.4 to 1.6, 1.0 to 1.0 and 2.2 to 2.6 mm, respectively. Median of NT-MoM values ranged from 0.83 to 0.95. Analysis of the distribution of NT measurements confirmed departure from the assumptions of the delta-NT and NT-MoM models. Analysis of LR distributions demonstrated a significant difference between observed and expected distributions for all operators (P < 10(-4) ).

CONCLUSION

An LR-based quality control process is feasible at 11-14 weeks of gestation. Because it is more sensitive to measurement bias around the critical area of the 95(th) centile, its use should be encouraged.

Phytosterol ester processing in the small intestine: impact on cholesterol availability for absorption and chylomicron cholesterol incorporation in healthy humans

Phytosterols (plant sterols and stanols) can lower intestinal cholesterol absorption, but the complex dynamics of the lipid digestion process in the presence of phytosterol esters (PEs) are not fully understood. We performed a clinical experiment in intubated healthy subjects to study the time course of changes in the distribution of all lipid moieties present in duodenal phases during 4 h of digestion of meals with 3.2 g PE (PE meal) or without (control meal) PE. In vitro experiments under simulated gastrointestinal conditions were also performed. The addition of PE did not alter triglyceride (TG) hydrolysis in the duodenum or subsequent chylomicron TG occurrence in the circulation. In contrast, cholesterol accumulation in the duodenum aqueous phase was markedly reduced in the presence of PE (-32%, P < 0.10). In vitro experiments confirmed that PE reduces cholesterol transfer into the aqueous phase. The addition of PE resulted in a markedly reduced presence of meal-derived hepta-deuterated cholesterol in the circulation, i.e., in chylomicrons (-43%, PE meal vs. control; P < 0.0001) and plasma (-54%, PE meal vs. control; P < 0.0001). The present data show that addition of PE to a meal does not alter TG hydrolysis but displaces cholesterol from the intestinal aqueous phase and lowers chylomicron cholesterol occurrence in humans.

A novel tumor-associated pancreatic glycoprotein is internalized by human dendritic cells and induces their maturation

Aberrant glycosylation or overexpression of cell-surface glycosylated tumor-associated Ags (TAA) distinguish neoplastic from normal cells. Interactions of TAA MUC1 and HER2/neu with dendritic cells (DC) preclude efficient processing, which impairs immune responses. It is thus important to define the mechanisms of interactions between DC and glycosylated TAA and their trafficking and processing for further T cell activation. In this work, we study interactions between DC and the oncofetal fucose-rich glycovariants of bile salt-dependent lipase (BSDL), expressed in pancreatic cancer tissues and referred to as pathological BSDL carrying the fucosylated J28 glycotope (pBSDL-J28) because it is characterized by the mAb J28. The expression of pBSDL-J28 was assessed by immunohistochemistry and quantified by confocal microscopy. Nontumoral pancreatic tissues and cells do not express pBSDL-J28. Using multidisciplinary approaches and functional studies, we provide the first evidence, to our knowledge, that this tumoral glycoprotein is rapidly internalized by human DC through macropinocytosis and endocytosis via mannose receptors and then transported to late endosomes for processing. Interestingly, pBSDL-J28 per se induced DC maturation with increased expression of costimulatory and CD83 molecules associated with cytokine secretion (IL-8 and IL-6). Surprisingly, DC retained their full ability to internalize Ags, making this maturation atypical. Finally, the allogeneic pBSDL-J28-treated DC stimulated lymphocyte proliferation. Besides, pulsing DC with pBSDL-J28 C-terminal glycopolypeptide and maturation with CD40L triggered CD4(+) and CD8(+) T cell proliferation. Therefore, interactions of pBSDL-J28, expressed on tumoral pancreatic tissue, with DC may lead to adequate Ag trafficking and processing and result in T cell activation.

Validity of sonographic prediction of fetal weight and weight discordance in twin pregnancies

OBJECTIVES

The aims of this study were (1) to assess the accuracy of estimated fetal weight (EFW) in twins and (2) to assess the accuracy of sonographic examination to predict birth weight discordance (BWD).

METHODS

We retrospectively analyzed collected data on twin pregnancies between 2004 and 2007. All twin pregnancies with at least one ultrasound (US) examination within 15 days of delivery were included in this study. EFW was calculated according to Hadlock1, Hadlock2, Ong, Shepard and Warsof formulas. Mean and SD of the standardized errors and percentage of newborns with birth weight (BW) within 10% of EFW were calculated.

RESULTS

Two hundred eighty-three twin pregnancies were included. Mean and SD (%) of the standardized errors were 1.54 +/- 12.19, 0.19 +/- 11.87, 10.93 +/- 15.55, - 1.91 +/- 14.93 and 5.37 +/- 14.91 for Hadlock1, Hadlock2, Shepard, Ong and Warsof formulas, respectively. Hadlock2's formula allowed for the highest proportion of newborns with BW within 10% of EFW and it also performed best to predict discordance of more than 25% as assessed by area under the ROC curve.

CONCLUSIONS

Sonographic prediction of inter-twin BWD within 15 days of delivery seems to be accurate enough for routine clinical use. Performance and predictive values depend on the threshold chosen to define EFW and BW discordance.

Predicting late-onset growth abnormalities using growth velocity between trimesters

OBJECTIVES

To determine whether growth velocity parameters derived from routine prenatal ultrasound measurements at first, second and third trimester can identify normal growth at term as well as late-onset growth abnormalities.

MATERIAL AND METHODS

Longitudinal study of fetal growth in normal singleton pregnancies with three normal ultrasound examinations and delivered at term. Fetuses were classified into 3 groups (<10th percentile, 10-90th percentile, >90th percentile) based on birth weight. Multiple regression on birth weight classification was used to build up a prediction equation of fetal growth potential (FGP) based on fetal biometry and fetal growth velocity parameters between ultrasound examinations. Best cut-off value for FGP predicting growth restriction and macrosomia were defined.

RESULTS

356 pregnancies were included. Fetal biometry growth velocities between examinations were calculated for all measurements. Using best cut-off values, the estimated sensitivity, specificity and odds ratio were: 60% [44;74], 91% [89;92] and 14.55 [6.30;33.98] and 53% [36;69], 89% [88;91] and 10 [4.27;23.49] for the prediction of growth restriction and macrosomia, respectively.

DISCUSSION

Fetal growth potential can be derived and calculated from standard ultrasound measurements. It can improve identification of these fetuses at risk for late-onset growth abnormalities and their related morbidity.

The impact of crown-rump length measurement error on combined Down syndrome screening: a simulation study

OBJECTIVE

To evaluate the impact of a 5-mm error in the measurement of crown-rump length (CRL) in a woman undergoing ultrasound and biochemistry sequential combined screening for Down syndrome.

METHODS

Based on existing risk calculation algorithms, we simulated the case of a 35-year-old-woman undergoing combined screening based on nuchal translucency (NT) measurement and early second-trimester maternal serum markers (human chorionic gonadotropin (hCG) and alpha-fetoprotein (AFP) expressed as multiples of the median (MoM)). Two measurement errors were considered (+ or - 5 mm), for four different CRLs (50, 60, 70 and 80 mm), with five different NT measurements (1, 1.5, 2, 2.5 and 3 mm) in a patient undergoing biochemistry testing at 14 + 4, 15, 16, 17 or 18 weeks' gestation. Four different values for each maternal serum marker were tested (1, 1.5, 2 and 2.5 MoM for hCG, and 0.5, 0.8, 1 and 1.5 MoM for AFP), leading to a total of 3200 simulations of the impact of measurement error. In all cases the ratio between the risk as assessed with or without the measurement error was calculated (measurement error-related risk ratio (MERR)).

RESULTS

Over 3200 simulated cases, MERR ranged from 0.53 to 2.14. In 586 simulations (18.3%), it was < 0.66 or > 1.33. Based on a risk cut-off of 1/300, women would have been misclassified in 112 simulations (3.5%). This would go up to 33 (27.5%) out of the 120 simulations in women with 'borderline' risk, with 1.5 MoM for hCG and 0.5 MoM for AFP, and NT measurement of 1 or 2mm.

CONCLUSION

Down syndrome screening may be highly sensitive to measurement errors in CRL. Quality control of CRL measurement should be performed together with quality control of NT measurement in order to provide the highest standard of care.

Reference range for cervical length throughout pregnancy: non-parametric LMS-based model applied to a large sample

OBJECTIVE

Short cervical length is an important risk factor for preterm delivery. However, because cervical length changes throughout pregnancy, adequate risk estimation needs to take into account the gestational age (GA) at which the measurement is taken. We aimed to model cervical changes throughout pregnancy in order to be able to use Z-scores, avoiding the confounding effect of GA.

METHODS

Cervical length was prospectively measured in singleton pregnancies, as part of routine antenatal care over a 3-year period. Measurements were taken at GA ranging from 16 to 36 weeks and only one measurement per pregnancy was used in the analysis. Because cervical length measurements are not normally distributed, we used a non-parametric approach (LMS method) to best describe the distribution of the measurements with gestation.

RESULTS

We included 6614 cervical length measurements. The LMS method identified changes in cervical length measurement across GA. We computed new reference charts and provide L, M and S values that allow the calculation of Z-score at any GA from any cervical length measurement 'Y' using the formula: Z-score = ((Y/M)(L) - 1)/(L x S).

CONCLUSION

Cervical length measurements do not have a normal distribution at a given GA and so require a statistical model that takes this into account. The model that we developed allows easy Z-score calculation, therefore avoiding the confounding effect of GA and allowing straightforward monitoring of cervical length.

Methadone and impairment in apprehended drivers

AIMS

According to Norwegian guidelines, patients who are in opioid-assisted rehabilitation programmes are permitted to drive a motor vehicle provided that certain requirements are met. The purpose of this study was to investigate apprehended drivers who had methadone in their blood at the time of apprehension and, further, the relationship between blood methadone concentration and impairment as measured by the clinical test of impairment (CTI).

METHODS

The division of Forensic Toxicology and Drug Abuse (DFTDA) at the Norwegian Institute of Public Heath analyses blood samples from all drivers suspected of driving under the influence of drugs nation-wide. Cases with positive results for methadone in blood were collected over the period 2001-2006.

RESULTS

A total of 635 drivers with methadone found in their blood samples were identified. The majority of drivers were men (>80%), aged between 30 and 40 years. Methadone was the only psychoactive drug detected in blood in only 10 cases. Benzodiazepines were a frequent finding (in approximately 90% of cases). A significant difference in blood methadone concentration was found between cases where only methadone was detected [median 0.46 mg/l (range 0.19-0.65)] and cases where methadone was detected in combination with other psychoactive drugs [median 0.28 mg/l (range 0.06-1.24)]. A CTI had been carried out, in conjunction with blood sampling, in 577 of the cases. A concentration-impairment relationship was not seen for methadone in these cases.

CONCLUSIONS

Cases of driving impairment involving methadone alone were very rare, with combination use most frequent. No correlation between methadone concentration and impairment as judged by the CTI was seen either for these cases or for the material as a whole.

High histone deacetylase 7 (HDAC7) expression is significantly associated with adenocarcinomas of the pancreas

BACKGROUND

Alterations in HDACs gene expression have been reported in a number of human cancers. No information is available concerning the status of HDACs in pancreatic cancer tumors. The aim of the present study was to evaluate the expression levels of members of class I (HDAC1, 2,, 3), class II (HDAC4, 5, 6, and 7), and class III (SIRT1, 2, 3, 4, 5, and 6) in a set of surgically resected pancreatic tissues.

METHODS

Total RNA was isolated from 11 pancreatic adenocarcinomas (PA): stage 0 (n = 1), IB (n = 1), IIB (n = 6), III (n = 1), IV (n = 2), one serous cystadenoma (SC), one intraductal papillary mucinous tumor of the pancreas (IMPN), one complicating chronic pancreatitis (CP), and normal pancreas (NP) obtained during donor liver transplantation. Moreover, six other control pancreatic were included. HDACs gene expression was conducted using quantitative real-time polymerase chain reaction (qPCR). Protein expression levels were analyzed by Western blot and their localization by immunohistochemistry analyses of cancer tissues sections.

RESULTS

Remarkably, 9 of the 11 PA (approximately 81%) showed significant increase of HDAC7 mRNA levels. In contrast to PA samples, message for HDAC7 was reduced in CP, SC, and IMPN specimens. The Western blot analysis showed increased expression of HDAC7 protein in 9 out of 11 PA samples, in agreement with the qPCR data. Most of the PA tissue sections examined showed intense labeling in the cytoplasm when reacted against antibodies to HDAC7.

CONCLUSION

The data showed alteration of HDACs gene expression in pancreatic cancer. Increased expression of HDAC7 discriminates PA from other pancreatic tumors.

First-trimester ultrasound examination and the outcome of monochorionic twin pregnancies

OBJECTIVE

To refine the incidence of abnormal first-trimester ultrasound measurements and their correlation with the outcome of monochorionic diamniotic pregnancies.

METHODS

First-trimester crown-rump length (CRL) and nuchal translucency thickness (NT) measurements were studied in three subgroups of a total of 200 monochorionic twin gestations referred to our center between June 2002 and February 2006. Intertwin CRL discordance was defined as > 10% and the 95th percentile of NT thickness for gestational age was used. The first group of 103 consecutive unselected monochorionic diamniotic twin pregnancies was prospectively followed up from 11-14 weeks onwards, throughout the pregnancy. The second group of 136 nonconsecutive monochorionic diamniotic twin pregnancies including 64 that developed TTTS was studied retrospectively. The third group of 100 consecutive cases of TTTS studied retrospectively for the correlation between first trimester measurements and staging and timing of occurrence of TTTS.

RESULTS

In group 1, the incidence of TTTS was 5 in 103 (5%, 95CI [0.7-9]). Large intertwin CRL discordance and increased NT were correlated with perinatal death. In group 2, no significant association was found between first-trimester parameters and the development of TTTS but discordance in early second trimester biometry and Doppler were. In group three, a positive correlation was found between the intertwin discordance in CRL and early occurrence of TTTS before 20 weeks of gestation (p = 0.02).

CONCLUSION

Monochorionic twin gestations who ultimately develop TTTS may exhibit intertwin difference in growth as early as 11-14 weeks of gestation. The earlier the discordance the earlier the development of the disease.

Reference ranges for fetal ventricular width: a non-normal approach

OBJECTIVES

Normal ranges for fetal cerebral ventricular width are usually based on parametric methods, which define cut-off values based on means and standard deviations. We aimed to construct reference charts based on a large sample and using a method that better fits with skewed measurements.

METHODS

In November 2001-December 2005, a single operator, who was unaware of the subsequent analysis, performed prospectively and routinely fetal cerebral ventricular width measurements. We used the LMS method (which summarizes the changing distribution of a variable of interest according to a covariate (gestational age) using three curves representing the median (M), the coefficient of variation (S) and skewness (L)) to describe the distribution of measurements with gestational age. The LMS method provides a general method for fitting smooth centile curves to reference data. It utilizes the power transformation family of Box and Cox to allow the skewness of the measurement distribution, as well as the median and variability, to vary with age. The theoretical proportion of fetal ventricular widths > or = 10 mm based on the LMS method and on methods based on the assumption of normality were compared with the actual proportion using binomial tests. The influence on ventricular size of gestational age and fetal gender and presentation was assessed using robust regression methods.

RESULTS

Included in the study were 4769 ventricular measurements, 42 (0.88%) of which were > or = 10 mm. The LMS method allowed us to fit the skewness of the measurements and identified slight changes throughout gestation. The actual proportion of measurements > or = 10 mm was not different from that expected according to the LMS method (0.88% vs. 1%, P = 0.25), whereas it was significantly different from that based on the classical normal approximation (0.88% vs. 0.4%, P < 0.0001). There was a significant difference with gender (males: + 0.29 +/- 0.042 mm as compared to females, P < 0.0001), but there was no difference with fetal presentation (P = 0.4).

CONCLUSION

We present new reference values for fetal ventricular width based on the LMS method. A fixed cut-off value of 10 mm identifies around 1% of the population throughout gestation, which is more than that calculated in previous studies.

Relationship between methadone and EDDP (2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine) in urine samples from Norwegian prisons

BACKGROUND

Methadone maintenance treatment is a widely used therapy in the rehabilitation of opioid addiction the world over. Methadone is metabolised in the body to a number of inactive metabolites, but primarily to 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP). The Division of Forensic Toxicology and Drug Abuse (DFTDA) of the Norwegian Institute of Public Health carries out drug analysis of urine samples from inmates of prisons throughout Norway. Methadone and EDDP in the urine are also tested for upon request. The results are stored in a secure database at the DFTDA.

OBJECTIVES

The aims of the present study were (1) to observe variations in methadone and EDDP concentrations in urine in relation to urine pH in a large set of urine samples obtained from prison inmates and (2) to analyse samples testing methadone-positive/EDDP-negative and investigate whether such results could occur naturally, without sample tampering.

METHODS

All urine samples that tested positive for methadone over the period 2004-2005 were collected from the DFTDA database, and the relation between methadone and EDDP excretion in urine, and urinary pH was determined. Samples that tested positive for methadone but negative for EDDP were picked out and studied individually.

RESULTS

A total of 1539 urine samples (cases) had tested positive for methadone in our database for the period 2004-2005. There was a strong correlation between the concentration of methadone in urine and urine pH in these samples, with higher concentrations of methadone present at lower pH levels. Cases that tested positive for methadone but negative for EDDP were rare - a total of five (0.3% of all cases tested). These cases were studied in more detail.

CONCLUSION

Methadone excretion in urine is dependent on urinary pH. Methadone-positive/EDDP-negative results may suggest sample tampering in some, but not all, cases.

Estimation of fetal weight: reference range at 20-36 weeks' gestation and comparison with actual birth-weight reference range

OBJECTIVES

To formulate reference charts and equations for estimated fetal weight (EFW) from a large sample of fetuses and to compare these charts and equations with those obtained for birth weight during the same study period and in the same single health authority.

METHODS

Biometric data were obtained at 20-36 weeks' gestation from routine screening examinations spanning 4 years. Exclusion criteria were a known abnormal karyotype or congenital malformation and multiple pregnancy. No data were excluded on the basis of abnormal biometry. EFW was calculated based on Hadlock's formula. We used a polynomial regression approach (mean and SD model) to compute a new reference chart for EFW. This chart was compared with that of birth weight at 25-36 weeks' gestation during the same study period and in the same health authority.

RESULTS

18,959 fetuses were included in the study. New charts and equations for Z-score calculations at 20-36 weeks' gestation are reported. Comparison with the birth-weight chart showed that the EFW was noticeably larger at 25-36 weeks' gestation. At 28-32 weeks' gestation, the 50th centile for birth weight compared approximately with the 10th centile for EFW.

CONCLUSION

We present new reference charts and equations for EFW. EFW is computed throughout gestation based on measurements in healthy fetuses. However, before full term, birth-weight charts reflect a significant proportion of growth-restricted fetuses that deliver prematurely. We provide additional evidence that comparing EFW with birth-weight charts is misleading.

Glycoengineering of alphaGal xenoantigen on recombinant peptide bearing the J28 pancreatic oncofetal glycotope

In human pancreatic adenocarcinoma, alterations of glycosylation processes leads to the expression of tumor-associated carbohydrate antigens, representing potential targets for cancer immunotherapy. Among these pancreatic tumor-associated carbohydrate antigens, the J28 glycotope located within the O-glycosylated mucin-like C-terminal domain of the fetoacinar pancreatic protein (FAPP) and expressed at the surface of human tumoral tissues, can be a good target for anticancer therapeutic vaccines. However, the oncodevelopmental self character of the J28 glycotope associated with the low immunogenicity of tumor-associated carbohydrate antigens may be a major obstacle to effective anti-tumor vaccine therapy. In this study, we have investigated a method to increase the immunogenicity of the recombinant pancreatic oncofetal J28 glycotope by glycoengineering Galalpha1,3Galss1,4GlcNAc-R (alphaGal epitope) which may be recognized by natural anti-alphaGal antibody present in humans. For this purpose, we have developed a stable Chinese hamster ovary cell clone expressing the alphaGal epitope by transfecting the cDNA encoding the alpha1,3galactosyltransferase. These cells have been previously equipped to produce the recombinant O-glycosylated C-terminal domain of FAPP carrying the J28 glycotope. As a consequence, the C-terminal domain of FAPP produced by these cells carries the alphaGal epitope on oligosaccharide structures associated with the J28 glycotope. Furthermore, we show that this recombinant "alpha1,3galactosyl and J28 glycotope" may not only be targeted by human natural anti-alphaGal antibodies but also by the mAbJ28, suggesting that the J28 glycotope remains accessible to the immune system as vaccinating agent. This approach may be used for many identified tumor-associated carbohydrate antigens which can be glycoengineered to carry a alphaGal epitope to increase their immunogenicity and to develop therapeutic vaccines.

Frequency and characteristics of pancreatitis in patients with inflammatory bowel disease

BACKGROUND AND AIMS

Clinical symptoms of inflammatory bowel disease (IBD)-associated pancreatitis are found in approximately 2% of patients, but the frequency of the disease could be much higher since IBD-associated pancreatitis could be mainly a silent disease. The aim of this study was to describe the radiological and biological features of IBD-associated pancreatitis and assess its frequency by comparing data from IBD patients with or without a history of pancreatitis.

METHODS

79 patients were prospectively enrolled (median age 36 years). Symptoms of pancreatitis had been previously recorded in 30 of them (group P; the other 49 patients (group C) had no history of pancreatitis. Pancreatic ductal changes were investigated by pancreato-MRI. Exocrine function was assessed by the fecal elastase test and by assaying serum amylase, lipase, C-reactive protein, PAP, IgG4 and pancreatic autoantibodies.

RESULTS

Increased levels of amylase and lipase occurred in 11% of IBD patients, that frequency being significantly higher in group P (23%) than in group C (4%) (p = 0.01). Low fecal elastase reflecting impaired exocrine function was observed in 30% of patients and again significantly more in group P (50%) than in group C (17%) (p = 0.04). The frequency of elevated values varied from 12% for amylase and lipase to 18% for PAP, 20% for pancreatic autoantibodies and 45% for CRP, without a difference between groups P and C. Silent exocrinopathy was observed in both groups, pancreatic autoantibodies and pancreatic duct alterations being found in 20 and 11% of patients, respectively.

CONCLUSION

Finding pancreatic insufficiency in about 30% of the included patients and in 50% of those with a previous history of pancreatitis suggests that IBD might be associated with chronic pancreatic alteration. Episodes of mild acute pancreatitis observed in some patients are not always due to adverse effects of treatments and can be acute manifestations of the chronic disease.

[The consortium of Biological Resource Centres (BRC) and tumour cell and tissue banks in the Marseilles metropolitan area]

The goal of this presentation is to describe current and future aspects of the operations within the consortium of Biological Resource Centres (BRC) and Tumour cell and tissue banks of the Marseilles metropolitan area. The consortium was created in year 2001, through the association of several tissue and cell banks that were operating for many years in Marseilles. Existing collections are not exclusively collections of tumour cells or tissues; however, the two tumour cell and tissue banks located at the Regional Cancer Research Centre and at the University Hospital account for a very significant proportion of the collections. Our collective work leads to the recognition and funding of the consortium by Inserm, through the "Collections 2003" grant. The consortium objectives are to define a common scientific strategy, to share professional practices in the logistics and database management of the banks, to establish a quality management program, and to build a common catalogue that describes existing biological resources. Through these efforts, the ultimate goal is to adopt rules that define BRC, as defined by the Organization for Economic Co-operation and Development (OECD).

Feasibility and reproducibility of an image-scoring method for quality control of fetal biometry in the second trimester

OBJECTIVES

The need for training programs and certification processes in fetal ultrasound has become obvious. The purpose of this study was to evaluate the feasibility of a score-based quality control system for fetal biometry in the second trimester.

METHODS

Standard measurements of biparietal diameter and head circumference, abdominal circumference, and femur length at 20-24 weeks had been made by four operators using the same ultrasound machine. Twenty-five of each of the cephalic, abdominal and femoral images with the calipers in place were selected arbitrarily from each operator's ultrasound database and anonymized. These 300 images were analyzed by three experienced reviewers blinded to the operator's identity. Each image was first evaluated subjectively and then scored according to six criteria for abdominal and cephalic measurements and four criteria for femur length making a six-point score for abdominal and cephalic biometry and a four-point score for femur length. For subjective evaluation, inter-reviewer differences were analyzed using percentage agreement and adjusted kappa. For objective evaluation, a difference in scoring of one point or less among reviewers was considered good agreement. Intrareviewer variability was assessed using 40 images of each type of examination selected arbitrarily.

RESULTS

The distribution of scores was similar between reviewers. One operator obtained significantly lower scores whereas the other three had good and comparable results. There was no statistical difference in the mean score attributed by each reviewer and agreement was good in 84-90% of the cases. Intrareviewer agreement was good in 90-100% of the cases, with similar scores for each reviewer.

CONCLUSION

A quality control policy based on image scoring is feasible and allows for fair to good inter- and intrareviewer reproducibility. The potential contribution of this approach to assess the quality of routine ultrasound examinations should be tested on a larger scale.

Analysis of Z-score distribution for the quality control of fetal ultrasound measurements at 20-24 weeks

OBJECTIVES

To develop and evaluate the feasibility of Z-score distribution-based quality assessment for fetal biometry at 20-24 gestational weeks.

METHODS

Four sonographers measured fetal biparietal diameter, head circumference, abdominal circumference and femur length in unselected pregnancies undergoing routine sonography at 20-24 weeks in our center between June 2001 and January 2004. All measurements were transformed into Z-scores. Distributions of Z-scores were compared with the expected standard normal distribution based on mean, SD and the Kolmogorov-Smirnov test. Modelling was performed to assess the sensitivity, specificity and Youden's index (sensitivity + specificity - 1) of each sonographer, reflecting their ability to detect fetuses with abnormal biometry in our population.

RESULTS

A total of 5241 ultrasound examinations were included. None of the Z-score distributions could be considered similar to the standard normal distribution: means of Z-scores ranged from -0.604 to 0.73 and the SD ranged from 0.726 to 0.896. Sensitivity and specificity ranged from 25.31% to 68.67% and 93.44% to 100%, respectively; Youden's index ranged from 0.25 to 0.69.

CONCLUSION

Analysis of Z-score distribution can be used to assess the quality of fetal measurements. Several indices can be extracted from this analysis in order to improve quality assessment of fetal biometry measured by ultrasound.

Growth discrepancy in twins in the first trimester of pregnancy

OBJECTIVE

The prevalence and significance of intertwin growth discrepancy in the first trimester of pregnancy are controversial. The aim of this study was to refine the incidence and outcome of this discrepancy in relation to dating of the pregnancy and other biometric parameters.

METHODS

This prospective study of twin pregnancies initially evaluated at 11-14 weeks' gestation was conducted between 2001 and 2004. Differences in crown-rump length (CRL) and estimated gestational age (GA) were calculated for each twin pair and their distribution was analyzed according to chorionicity and mode of conception (spontaneous or following assisted reproductive technologies). CRL-based GA and actual GA were compared. Other biometric parameters were also compared for each twin pair. The distribution of discrepancies was analyzed according to pregnancy outcome.

RESULTS

A total of 182 twin pregnancies was included. The mean+/-SD discrepancy in CRL was 3.4+/-3.18 mm or 5.1+/-4.69% and the 95th centile was 9.8 mm or 14.3%. There was no influence of chorionicity (P=0.44), mode of conception (P=0.18) and no relation with outcome (P=0.54). In conceptions resulting from assisted technology, the measured CRL of the smaller twin was closer to the actual GA. Cephalic and abdominal biometric measurements were significantly greater in the twin with the smaller CRL (P<0.05). The two cases with a discrepancy>15 mm were affected by trisomy 18 and triploidy, respectively.

CONCLUSIONS

CRL discrepancy in twin pregnancies in the first trimester is a frequent finding. Discrepancy>95th centile indicates major growth delay of one twin, which could indicate the presence of aneuploidy. For milder degrees of discordance the CRL of the smaller fetus is a more accurate estimate of the actual GA.

The impact of choice of reference charts and equations on the assessment of fetal biometry

OBJECTIVES

The assessment of fetal biometry is usually based on the comparison of measured values with predicted values derived from reference charts or equations in a normal population. This study was undertaken to assess the impact of the choice of reference charts and to develop a Z-score-based tool that could help sonographers to choose the reference charts that best fit their practice.

METHODS

Fetal biparietal diameter, head circumference, abdominal circumference and femur diaphysis length measurements were made at 20-24 and 30-34 weeks' gestation by four experienced sonographers. All measurements were transformed into Z-scores calculated according to three prediction equations (Snijders and Nicolaides, 1994; Chitty et al., 1994 and Kurmanavicius et al., 1999). Distributions of Z-scores were compared to the expected standard normal distribution based on mean, SD and Kolmogorov-Smirnov test. Simulations were made to assess sensitivity (Se), specificity (Sp) and Youden's index (Se + Sp - 1) of each reference equation, reflecting their ability to identify fetuses with abnormal biometry in our population. The reference that best fitted our practice was determined based on these results.

RESULTS

The Z-scores of all biometric parameters were significantly different (P < 0.001) when using any of the three reference equations, and none of the Z-score distributions could be considered similar to the standard normal distribution. The number of measurements that would be considered as abnormal according to these references ranged from 2.6% to 23.6%. Se and Sp ranged from 39.59% to 67.12% and 90.14% to 99.69%, respectively.

CONCLUSION

Assessment of fetal biometry is largely dependent on the choice of reference charts. We suggest that the choice of reference charts for fetal biometry could be controlled using Z-scores in each institution and that this could be the first step towards any quality assessment policy. The method we describe for the choice of the most appropriate fetal biometry reference chart might be used for all size charts.

Monoclonal antibody 16D10 to the C-terminal domain of the feto-acinar pancreatic protein binds to membrane of human pancreatic tumoral SOJ-6 cells and inhibits the growth of tumor xenografts

Feto-acinar pancreatic protein (FAPP) characterized by mAbJ28 reactivity is a specific component associated with ontogenesis and behaves as an oncodevelopment-associated antigen. We attempted to determine whether pancreatic tumoral SOJ-6 cells are expressed at their surface FAPP antigens and to examine if specific antibodies directed against these FAPP epitopes could decrease the growth of pancreatic tumors in a mice model. For this purpose, we used specific antibodies against either the whole FAPP, the O-glycosylated C-terminal domain, or the N-terminal domain of the protein. Our results indicate that SOJ-6 cells expressed at their surface a 32-kDa peptide corresponding to the C-terminal domain of the FAPP. Furthermore, we show, by using endoproteinase Lys-C or geldanamycin, a drug able to impair the FAPP secretion, that this 32-kDa peptide expressed on the SOJ-6 cell surface comes from the degradation of the FAPP. Finally, an in vivo prospective study using a preventative tumor model in nude mice indicates that targeting this peptide by the use of mAb16D10 inhibits the growth of SOJ-6 xenografts. The specificity of mAb16D10 for pancreatic tumors and the possibility to obtain recombinant structures of mucin-like peptides recognized by mAb16D10 and mAbJ28 are promising tools in immunologic approaches to cure pancreatic cancers.

First-trimester screening for fetal triploidy at 11 to 14 weeks: a role for fetal biometry

OBJECTIVE

Intrauterine growth restriction in triploidy has been reported as early as in the first trimester. This study was undertaken to evaluate the ability of first-trimester crown rump length (CRL)-based charts to detect triploid fetuses.

MATERIAL AND METHODS

Analysis of fetal biometry in cases of triploidy diagnosed in the first trimester over the last three years. Biometry for abdominal circumference (AC), head circumference (HC) and biparietal diameter (BPD) was analyzed in relation to both gestational age (GA)-based charts and to CRL-based charts.

RESULTS

Five cases of fetal triploidy were diagnosed at 11 to 14 weeks. Screening based on nuchal translucency (NT) and maternal age showed a risk > 1/300 in only one of the 5 cases of triploid fetus. In all of these five cases, CRL-based biometry was grossly abnormal, although it was abnormal in only two of these five cases in relation to GA-based charts.

CONCLUSION

First-trimester CRL-based biometry charts seem to reflect early asymmetrical growth delay in triploidy more accurately than GA-based charts. CRL-based biometry is likely to improve the early detection of triploid pregnancies without leading to dating error.

Relationship between ?Gal epitope expression and decrease of tumorigenicity in pancreatic adenocarcinoma model

The alphaGal epitope is a carbohydrate structure, Galalpha1,3Galbeta1,4GlcNAc-R, synthesized on glycoconjugates in many mammals by alpha1,3galactosyltransferase. Humans do not express this epitope and present in serum large amounts of naturally occuring antibodies, which recognize the alphaGal epitopes and participate in the hyperacute rejection of xenograft. Studies indicated that the fundamental mechanism of hyperacute rejection involving the alphaGal epitope expression can be used in cancer therapy. We have previously suggested that the alphaGal epitope expression by human pancreatic tumoral cells could decrease the tumorigenic behavior of these cells. To determine whether the expression of the alphaGal epitope can modify the tumorigenicity of pancreatic cancer cells, we used a Syrian golden hamster pancreatic adenocarcinoma experimental model. The expression of alphaGal epitopes in the Syrian golden hamster pancreatic cancer cell line HaP-T1 was obtained by selecting stable cell clones transfected with murine alpha1,3galactosyltransferase gene. The alphaGal epitope expression resulted in a delay in the tumoral development of HaP-T1 cells in vivo after allograft transplantation of Syrian golden hamsters (2.5-fold, P < 0.05) and of nude mice. This result is associated with an 100% increase in survival time of nude mice bearing tumors expressing the alphaGal epitope. Our results confirm that the cell surface expression of alphaGal epitope decreases the tumorigenic behavior of pancreatic cancer cells. This novel property may be useful for the development of cancer gene immunotherapy strategy.

Long-term vertical changes of the anterior maxillary teeth adjacent to single implants in young and mature adults. A retrospective study

AIM

To evaluate the effects of the tooth eruption process on the position of teeth adjacent to implant-borne restorations in adult patients compared to patients in their late adolescence.

SUBJECT AND METHODS

The sample included 28 patients divided into two groups. A "young adult" group consisting of 14 patients, aged from 15.5 to 21 years, and a "mature adult" group consisting of 14 patients, aged from 40 to 55 years. All patients presented missing anterior teeth, requiring insertion of 40 implant fixtures (16 central incisors, 12 lateral incisors, 12 canines). The implants were of the Straumann Dental Implant System, clinically and radiologically re-evaluated 1 year or more after the surgical procedure (mean interval=4.2 years). Assessment of the eruption of the adjacent teeth was performed using the implant as a stable point of reference: measurements of the different reference points were compared after implant placement and at follow-up examination.

RESULTS

In the "young adult" group, all patients showed infra-occlusion of the implant-supported crowns: the vertical step measured on radiographs varied between 0.1 and 1.65 mm. In the "mature adult" group, all patients showed a vertical difference between the teeth adjacent to the implant-supported crown and the implant: the measured step ranged from 0.12 to 1.86 mm. No difference was found in the amount of vertical eruption between male and female patients, nor according to localization of the implant.

CONCLUSION

Mature adults can exhibit major vertical steps after anterior restorations with osseointegrated fixtures to the same extent as adolescents or "young adult" individuals with residuous growth potential.

Biological properties of acid etched titanium implants: effect of sandblasting on bone anchorage

The SLA (sandblasted with large grit and acid etched) surface is a textured surface that has been documented to lead to a rapid and strong implant fixation. The purpose of the present study was to determine the contribution of sandblasting in addition to etching to implant anchorage. It was also aimed to determine if the pits carved during etching alone have a bone-interlocking capacity that leads to microanchorage between the implant and bone. SLA implants and machined-and-acid-etched (MA) implants were placed in the maxilla of Land Race pigs. After 10 weeks of healing, they were reverse torqued. The reverse torque of the SLA and MA implants was 157.29 +/- 38.04 N cm and 105.33 +/- 25.12 N cm, respectively. Sandblasting increased bone anchorage by 49.3%; the difference was statistically significant (p =.028). Bone was found attached to both surfaces; bone ingrowth was found in the pits of both surfaces. It is suggested that the two surfaces are able to generate bone interlocking and mechanical coupling at the interface. When finite-element modeling is performed with these surfaces, it is suggested that the bound mode be used instead of the slip mode.

Decrease of human pancreatic cancer cell tumorigenicity by alpha1,3galactosyltransferase gene transfer

The enzyme alpha1,3galactosyltransferase synthesizes the alphaGal epitope, a carbohydrate structure (Galalpha1,3Galbeta1,4GlcNAc-R), on glycoconjugates in lower mammals. The enzyme is absent in humans but large amounts of natural antibodies that recognize alphaGal epitopes are present in human serum. It is likely that these antibodies contribute to the host defense and participate in the hyperacute rejection of xenograft. Previous studies indicated that the glycosyltransferase gene transfer into tumoral cells can modify the structure of glycoconjugates at the cell surface and, as a consequence, modulates the metastatic and tumorigenic behaviors of these cells. The aim of our study was to determine whether the expression of alphaGal epitope can modify the tumorigenicity of human pancreatic cancer cells. The expression of alphaGal epitopes in the human pancreatic cancer cell lines BxPC-3 and Panc-1 was obtained by selecting stable cell clones transfected with murine alpha1,3galactosyltransferase gene. The expression of the enzyme activity in BxPC-3 and Panc-1 cells resulted in the formation at the cell surface of alphaGal epitopes that are recognized by human anti-alphaGal antibodies. alphaGal epitope expression at the surface of pancreatic cancer cells was associated with the fixation of complement 1q to human anti-alphaGal antibodies. The alphaGal epitope expression also resulted in a delay in the tumoral development of BxPC-3 and Panc-1 cells in vivo after xenograft transplantation of nude mice. In addition to the impairment of the metastatic potential of murine tumor cell lines and the activation of immune response, our study provides evidence that the cell surface expression of alphaGal epitopes also modulates the tumorigenic behavior of human pancreatic cancer cells.

Etched implants: A comparative surface analysis of four implant systems

Surface texturing by acid etching has recently become popular among dental implant manufacturers. The aim of this study was to compare the surface topography of four implant systems and to check the reproducibility of the industrial process of each implant system. Three implants per system have been selected from three distinct batches. They were observed under a scanning electron microscope (SEM), and roughness was determined with a contact profilometer by measuring five height-descriptive parameters (Ra, Rq, Rz(ISO), Rt, and Rsk, a texture parameter Sm, and a hybrid parameter RDeltaq. The analysis showed that each implant system displayed a distinct surface topography that could not be mistaken. When sandblasting was performed prior to etching, surface topography was a combination of macro- and microroughness. The roughness and the amount of remaining sand varied among the batches, showing that the industrial process is not fully developed. Deviation from the released technical information was found for two out of four implant manufacturers. Based on the available biological and clinical data on textured surfaces, it is suggested that it is bone interlocking at the interface that maintains the biological properties of textured surfaces, rather than a strong implant fixation per se.

The value of middle cerebral artery peak systolic velocity in the diagnosis of fetal anemia after intrauterine death of one monochorionic twin

OBJECTIVE

The purpose of this study was to assess the value of the fetal middle cerebral artery peak systolic velocity in the prediction of anemia within 24 hours of the death of one monochorionic twin in twin-to-twin-transfusion syndrome and to establish the correlation between middle cerebral artery peak systolic velocity and hemoglobin concentration in fetuses who are at risk for acute anemia.

STUDY DESIGN

Doppler examination of the middle cerebral artery peak systolic velocity was performed in 20 monochorionic survivors of pregnancies that were complicated by twin-to-twin-transfusion syndrome that occurred between 20 and 34 weeks of gestation. Doppler examination was performed before cordocentesis and after intrauterine transfusion when appropriate. Both hemoglobin concentration and middle cerebral artery peak systolic velocity were expressed in multiples of the median. Severe anemia was defined as hemoglobin concentration of <0.55 multiples of the median, and we used the cutoff point of 1.50 times the median values at any gestational age to calculate the sensitivity and specificity of middle cerebral artery peak systolic velocity in detecting moderate or severe anemia.

RESULTS

Fetal anemia was confirmed in 10 of 20 fetuses. We performed seven intrauterine transfusions. The sensitivity and specificity of middle cerebral artery peak systolic velocity in the prediction of severe fetal anemia were of 90%, with a false-negative rate of 10%. The correlation between peak systolic velocity and hemoglobin concentration both before and after transfusion was evaluated by regression analysis and was strongly significant.

CONCLUSION

In fetuses who are at risk of acute anemia, the measurement of middle cerebral artery peak systolic velocity was found to be a reliable noninvasive diagnostic tool and may be helpful in counseling and planning invasive assessment.

Intra- and interoperator variability in fetal nasal bone assessment at 11-14 weeks of gestation

OBJECTIVES

Examination of the fetal nasal bones by ultrasound between 11 and 14 weeks of gestation has been proposed as an additional tool in the detection of trisomy 21 in a high-risk population. However the variability in the identification of fetal nasal bones by ultrasound has not yet been investigated. The aim of this study was to assess the intraobserver and interobserver reproducibility of fetal nasal bone identification by ultrasound between 11 and 14 weeks of gestation.

METHODS

A total of 1040 consecutive ultrasound examinations were performed at 11-14 weeks of gestation for nuchal translucency (NT) measurement and nasal bone identification by ultrasound. A total of 657 consecutive video-loops were assessed by three experienced operators. Each operator assigned cases to one of three categories, namely present, uncertain or absent nasal bones, and the results were compared between operators. To assess the intraoperator variability each operator reviewed 100 randomly selected videos out of the 657 loops and again used the same classification. Results were compared by pairwise unweighted and weighted Kappa index to evaluate the inter- and intraoperator variability.

RESULTS

Among the 1040 fetuses, there were 51 (4.9%) with an NT measurement above the 95th centile. Nasal bones were identified by ultrasound in 948, not seen in eight and impossible to assess in 84 fetuses. Four fetuses had trisomy 21 including three with absent nasal bones and increased NT and one with present nasal bones and normal NT. The Kappa and weighted Kappa values for interoperator variability between the three operators were between 0.26 and 0.37 and 0.33 and 0.44, respectively. The Kappa and weighted Kappa values for intraoperator variability were between 0.35 and 0.48 and 0.43 and 0.55, respectively.

CONCLUSION

The assessment of fetal nasal bones is only fairly reproducible. Although the performance of the test in fetuses at high risk for trisomy 21 has been reported to be good, its implementation as an additional screening technique in the general population must be accompanied by teaching and quality control programs.

Comparison of fetal nasal bone assessment by ultrasound at 11-14 weeks and by postmortem X-ray in trisomy 21: a prospective observational study

OBJECTIVE

To compare nasal bone assessment by ultrasound examination at 11-14 weeks' gestation and postmortem X-ray examination in fetuses with trisomy 21.

METHODS

Twenty-one fetuses with trisomy 21 which had undergone sonographic examination at 11-14 weeks for measurement of nuchal translucency thickness and assessment of the nasal bones were examined by postmortem X-ray following termination of pregnancy.

RESULTS

The nasal bones were absent in 11/21 (52.4%) fetuses on ultrasound examination at 11-14 weeks and in 10/21 (47.6%) fetuses on X-ray examination at 14 to 25 + 5 weeks. Ultrasound and X-ray findings were discordant in 9/21 (42.9%) cases. Eight of 11 (72.7%) fetuses with absent nasal bones on ultrasound examination had a nuchal translucency thickness > 95th centile.

CONCLUSION

The high incidence of absent nasal bones in first-trimester fetuses with trisomy 21 is compatible with a developmental delay. Prior to inclusion of nasal bone assessment into risk calculation for trisomy 21, the independence of absence of nasal bones by ultrasound and increased nuchal translucency above the 95th centile at 11-14 weeks should be investigated more extensively.

Revisiting first-trimester fetal biometry

INTRODUCTION

Although advances in ultrasound have facilitated the diagnosis of fetal abnormalities in the first trimester, fetal biometry at this stage of pregnancy remains underused in prenatal diagnosis. We hypothesized that charts which directly correlate measurements to crown-rump length (CRL) could be more accurate than those based on gestational age (GA) derived from CRL measurement. The aim of this study was to construct CRL-based biometric charts.

METHODS

Measurements of biparietal diameter (BPD), head circumference (HC) and abdominal circumference (AC) were prospectively collected from 939 normal singleton fetuses. Charts and predictive equations were constructed from data obtained from pregnancies in which the CRL was between 45 and 84 mm and for which the outcome was normal.

RESULTS

Measurements of BPD, HC and AC from 880 fetuses who met the criteria were correlated with CRL and used to construct charts and predictive equations. The standard error of estimates using CRL was significantly lower than that using GA in all cases.

DISCUSSION

First-trimester growth charts and predictive equations based on CRL instead of GA are more accurate. They might have a role in quality control of first-trimester ultrasound examination and may help in the diagnosis of fetal conditions that involve early growth abnormalities.