Cooperation over conflict at the maternal-fetal interface

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Prediction of severe adverse neonatal outcomes at the second stage of labour using machine learning: a retrospective cohort study

OBJECTIVE

To create a personalised machine learning model for prediction of severe adverse neonatal outcomes (SANO) during the second stage of labour.

DESIGN

Retrospective Electronic-Medical-Record (EMR) -based study.

POPULATION

A cohort of 73 868 singleton, term deliveries that reached the second stage of labour, including 1346 (1.8%) deliveries with SANO.

METHODS

A gradient boosting model was created, analysing 21 million data points from antepartum features (e.g. gravidity and parity) gathered at admission to the delivery unit, and intrapartum data (e.g. cervical dilatation and effacement) gathered during the first stage of labour. Deliveries were allocated to high-risk and low-risk groups based on the Youden index to maximise sensitivity and specificity.

MAIN OUTCOME MEASURES

SANO was defined as either umbilical cord pH levels ≤7.1 or 1-minute or 5-minute Apgar score ≤7.

RESULTS

The model for prediction of SANO yielded an area under the receiver operating curve (AUC) of 0.761 (95% CI 0.748-0.774). A third of the cohort (33.5%, n = 24 721) were allocated to a high-risk group for SANO, which captured up to 72.1% of these cases (odds ratio 5.3, 95% CI 4.7-6.0; high-risk versus low-risk groups).

CONCLUSIONS

Data acquired throughout the first stage of labour can be used to predict SANO during the second stage of labour using a machine learning model. Stratifying parturients at the beginning of the second stage of labour in a 'time out' session, can direct a personalised approach to management of this challenging aspect of labour, as well as improve allocation of staff and resources.

TWEETABLE ABSTRACT

Personalised prediction score for severe adverse neonatal outcomes in labour using machine learning model.

The trial to reduce antimicrobial use in nursing home residents with Alzheimer's disease and other dementias: study protocol for a cluster randomized controlled trial

BACKGROUND

Infections are common in nursing home (NH) residents with advanced dementia but are often managed inappropriately. Antimicrobials are extensively prescribed, but frequently with insufficient evidence to support a bacterial infection, promoting the emergence of multidrug-resistant organisms. Moreover, the benefits of antimicrobials remain unclear in these seriously ill residents for whom comfort is often the goal of care. Prior NH infection management interventions evaluated in randomized clinical trials (RCTs) did not consider patient preferences and lack evidence to support their effectiveness in 'real-world' practice.

METHODS

This report presents the rationale and methodology of TRAIN-AD (Trial to reduce antimicrobial use in nursing home residents with Alzheimer's disease and other dementias), a parallel group, cluster RCT evaluating a multicomponent intervention to improve infection management for suspected urinary tract infections (UTIs) and lower respiratory tract infections (LRIs) among NH residents with advanced dementia. TRAIN-AD is being conducted in 28 facilities in the Boston, USA, area randomized in waves using minimization to achieve a balance on key characteristics (N = 14 facilities/arm). The involvement of the facilities includes a 3-month start-up period and a 24-month implementation/data collection phase. Residents are enrolled during the first 12 months of the 24-month implementation period and followed for up to 12 months. Individual consent is waived, thus almost all eligible residents are enrolled (target sample size, N = 410). The intervention integrates infectious disease and palliative care principles and includes provider training delivered through multiple modalities (in-person seminar, online course, management algorithms, and prescribing feedback) and an information booklet for families. Control facilities employ usual care. The primary outcome, abstracted from the residents' charts, is the number of antimicrobial courses prescribed for UTIs and LRIs per person-year alive.

DISCUSSION

TRAIN-AD is the first cluster RCT testing a multicomponent intervention to improve infection management in NH residents with advanced dementia. Its findings will provide an evidence base to support the benefit of a program addressing the critical clinical and public health problem of antimicrobial misuse in these seriously ill residents. Moreover, its hybrid efficacy-effectiveness design will inform the future conduct of cluster RCTs evaluating nonpharmacological interventions in the complex NH setting in a way that is both internally valid and adaptable to the 'real-world'.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03244917 . Registered on 10 August 2017.

Physician and Surrogate Agreement with Assisted Dying and Continuous Deep Sedation in Advanced Dementia in Switzerland

BACKGROUND

Assisted dying and continuous deep sedation (CDS) are controversial practices. Little is known about the perceptions of physicians and surrogates about these practices for patients with advanced dementia.

OBJECTIVES

To describe and compare physician and surrogate agreement with the use of assisted dying and CDS in advanced dementia.

DESIGN, SETTING, SUBJECTS

Physicians (n = 64) and surrogates (n = 168) of persons with advanced dementia were recruited as part of a randomized controlled trial in Switzerland that tested decision support tools in this population.

METHODS

At baseline, the participants were asked about their agreement with assisted dying and CDS in advanced dementia using the following response options: "completely agree," "somewhat agree," "somewhat disagree," "completely disagree," and "do not know." Multivariable logistic regressions compared the likelihood that surrogates versus physicians would completely or somewhat agree (vs. completely or somewhat disagree) with these practices.

RESULTS

The physicians and surrogates, respectively, had a mean age (SD) of 50.6 years (9.9) and 57.4 years (14.6); 46.9% (n = 30/64) and 68.9% (n = 115/167) were women. A total of 20.3% (n = 13/64) of the physicians and 47.0% (n = 79/168) of the surrogates agreed with assisted dying in advanced dementia. Surrogates were significantly more likely to agree with this practice than physicians (adjusted odds ratio, 3.87; 95% CI: 1.94, 7.69). With regard to CDS, 51.6% (n = 33/64) of the physicians and 41.9% (n = 70/169) of the surrogates agreed with this practice, which did not differ significantly between the groups.

CONCLUSIONS

The surrogates were more agreeable to considering assisted dying in the setting of advanced dementia than the physicians, and about half of the participants in both groups reported CDS to be an appropriate option for this population.

Experimental cryptorchidism enhances testicular susceptibility to dibutyl phthalate or acrylamide in Sprague-Dawley rats

Cryptorchidism (CPT), the most common male congenital abnormality, is variably associated with other male reproductive tract problems. We evaluated if cryptorchid rats develop enhanced testicular susceptibility to dibutyl phthalate (DBP) or acrylamide (AA) after extended exposure. Three studies with rats were performed: (1) in utero and postnatal exposure to DBP or AA; (2) establishment of CPT and orchiopexy; and (3) in utero and postnatal exposures to DBP or AA associated with CPT/orchiopexy. Seminiferous tubules were histologically scored according to the severity of lesions: (1) Rats exposed to DBP (score 1.5) or AA (score 1.1) presented mostly preserved spermatogenesis. Some seminiferous tubules showed vacuolated germinative epithelium, germ cell apoptosis, and a Sertoli cell-only (SCO) pattern. (2) CPT (score 3.3) resulted in decreased absolute testes weights, degenerated and SCO tubules, and spermatogenesis arrest that were reversed by orchiopexy (score 1.1). (3) Exposure to DBP or AA with CPT/orchiopexy led to atrophic testes, spermatogenesis arrest, germ cell exfoliation/multinucleation, and SCO tubules (both chemicals score 2.5). Exposure to chemicals such as DBP or AA prevented the recovery of cryptorchid testes by orchiopexy. The possible role of environmental contaminants should be considered when looking for factors that modulate human testicular disorders associated with CPT.

Fact Box decision support tools reduce decisional conflict about antibiotics for pneumonia and artificial hydration in advanced dementia: a randomized controlled trail

Background

fact Boxes are decision support tools that can inform about treatment effects.

Objectives

to test whether Fact Box decision support tools impacted decisional conflict, knowledge and preferences about the use of antibiotics and artificial hydration in advanced dementia.

Design

randomized controlled trial.

Setting

Swiss-German region of Switzerland.

Subjects

two hundred thirty-two participants (64 physicians, 100 relatives of dementia patients, 68 professional guardians) randomly allocated to intervention (N = 114) or control (N = 118).

Intervention

two-page Fact Box decision support tools on antibiotics for pneumonia and artificial hydration in advanced dementia (at 1-month).

Methods

participants were mailed questionnaires at baseline and one month later that asked questions about treatments based on hypothetical scenarios. The primary outcome was change in decisional conflict (DCS-D; range 0 < 100) about treatment decisions. Secondary outcomes included knowledge about treatments (range 0 < 7) and preferences to forego treatments.

Results

participants were: mean age, 55.6 years; female, 62.8%. Relative to control participants, intervention participants experienced less decisional conflict about using antibiotics (unstandardized beta (b) = -8.35, 95% Confidence Interval (CI), -12.43, -4.28) and artificial hydration (b = -6.02, 95% CI, -9.84, -2.20) at 1-month compared to baseline. Intervention participants displayed greater knowledge about the use of antibiotics (b = 2.24, 95% CI, 1.79, 2.68) and artificial hydration (b = 3.01, 95% CI, 2.53, 3.49), and were significantly more likely to prefer to forego antibiotics (odds ratio, 2.29, 95% CI, 1.08, 4.84) but not artificial hydration.

Conclusions

fact Box decision support tools reduced decisional conflict, increased knowledge and promoted preferences to forego antibiotics in advanced dementia among various decision-makers.

Trial registration

FORSbase (12091).

Concordance Between Proxy Level of Care Preference and Advance Directives Among Nursing Home Residents With Advanced Dementia: A Cluster Randomized Clinical Trial

CONTEXT

Care consistent with goals is the desired outcome of advance care planning (ACP).

OBJECTIVES

The objectives of this study were to examine concordance between advance directives and proxy care preferences among nursing home residents with advanced dementia and to determine the impact of an ACP video on concordance.

METHODS

Data were from Educational Video to Improve Nursing home Care in End-stage dementia, a cluster randomized clinical trial conducted in 64 Boston-area facilities (32/arm) from 2013 to 2017. Participants included advanced dementia residents and their proxies (N = 328 dyads). At the baseline and quarterly (up to 12 months), proxies stated their preferred level of care for the resident (comfort, basic, or intensive) and advance directives for specific treatments (resuscitation, hospitalization, tube-feeding, intravenous hydration, antibiotics) were abstracted from the charts. At the baseline, proxies in intervention facilities viewed an ACP video. Their care preferences after viewing it were shared via a written communication with the primary care team. At each assessment, concordance between directives and proxy preferences was determined.

RESULTS

Among the residents (mean age, 86.6 years; 19.5% male), the most prevalent directive was DNR (89.3%) and foregoing antibiotics was least common (parenteral, 8.2%; any type, 4.0%). Concordance between directives and each level of care preference was as follows: comfort, 7%; basic, 49%; and intensive, 58%. When comfort care was preferred, concordance was higher in intervention versus control facilities (10.8% vs. 2.5%; adjusted odds ratio, 2.48; 95% CI, 1.01-6.09).

CONCLUSION

Better alignment between preferences for comfort-focused care and advance directives is needed in advanced dementia. An ACP video may help achieve that goal.

Being present: oncologists' role in promoting advanced cancer patients' illness understanding

Realistic illness understanding is essential to an advanced cancer patient's ability to make informed medical decisions at the end of life. This study sought to determine whether advanced cancer patients better understood the late stage of their cancer if an oncologist, compared to other members of the care team, was present to discuss their scan results. Data were derived from a multi-institutional, longitudinal cohort study of patients recruited between 2010 and 2015. Patients (n = 209) with late-stage cancers (metastatic cancers that progressed after at least one chemotherapy regimen) were interviewed before and after clinic visits in which scan results were discussed. Patients reported pre- and postvisit if their cancer was at a late stage. Postvisit, patients reported if they discussed scan results with an oncologist or another oncology provider (i.e., oncology fellow, oncology resident, nurse practitioner, nurse, physician's assistant, or other). Logistic regression analysis was used to determine if the presence of an oncologist during scan results discussions differentially predicted the patients' likelihood of postvisit late-stage illness understanding (LSIU). Propensity weighting was used to correct for sociodemographic imbalances between groups, and previsit LSIU and the presence of multiple providers were controlled for in the logistic regression analyses. After propensity-weighted adjustment and controlling for previsit LSIU and the presence of multiple providers, patients were 2.6 times more likely (AOR = 2.6; 95% CI = 1.2, 6.0; P = 0.021) to report that their disease was late stage if an oncologist was present for the scan results discussion compared to if an oncologist was absent. The presence of an oncologist during scan results discussions was associated with a higher likelihood of patients acknowledging being in a late stage of their disease. These results suggest that oncologist involvement in scan results discussions is associated with advanced cancer patients having better prognostic understanding.

Understanding the origins of metal-organic framework/polymer compatibility

The microscopic interfacial structures for a series of metal-organic framework/polymer composites consisting of the Zr-based UiO-66 coupled with different polymers are systematically explored by applying a computational methodology that integrates density functional theory calculations and force field-based molecular dynamics simulations. These predictions are correlated with experimental findings to unravel the structure-compatibility relationship of the MOF/polymer pairs. The relative contributions of the intermolecular MOF/polymer interactions and the flexibility/rigidity of the polymer with respect to the microscopic structure of the interface are rationalized, and their impact on the compatibility of the two components in the resulting composite is discussed. The most compatible pairs among those investigated involve more flexible polymers, i.e. polyvinylidene fluoride (PVDF) and polyethylene glycol (PEG). These polymers exhibit an enhanced contact surface, due to a better adaptation of their configuration to the MOF surface. In these cases, the irregularities at the MOF surface are filled by the polymer, and even some penetration of the terminal groups of the polymer into the pores of the MOF can be observed. As a result, the affinity between the MOF and the polymer is very high; however, the pores of the MOF may be sterically blocked due to the strong MOF/polymer interactions, as evidenced by UiO-66/PEG composites. In contrast, composites involving polymers that exhibit higher rigidity, such as the polymer of intrinsic microporosity-1 (PIM-1) or polystyrene (PS), present interfacial microvoids that contribute to a decrease in the contact surface between the two components, thus reducing the MOF/polymer affinity.

Abstract PD8-01: Race and age differences in PAM50 biomarker status in the Carolina breast cancer study

Background: African American breast cancer patients have lower relative frequency of hormone receptor (HR)-positive/HER2-negative disease and higher subtype-specific mortality. However, few population-based studies have RNA-based subtyping data, and racial differences in the biology of HR-positive/HER2-negative tumors are not well understood.

Methods: Using data and biospecimens from the Carolina Breast Cancer Study (CBCS) Phase 3 (2008-2013), we classified approximately 1,000 invasive breast cancers according to PAM50 subtype and two risk of recurrence scores (ROR-P and ROR-PT). Relative frequency of Luminal A, Luminal B, Her2-enriched, and Basal-like subtypes and ROR scores (low/medium/high) were compared by race (blacks vs. whites) and age (≤50 years vs. &gt;50 years), overall and among HR-positive/HER2-negative cases.

Results: Black women of all ages had significantly higher relative frequency of Basal-like breast cancer (36 and 31% in blacks vs. 18 and 15% in whites; younger and older, respectively) and lower frequency of Luminal A breast cancer (26 and 34% in blacks vs. 43 and 52% in whites; younger and older, respectively). Frequency of Luminal B and HER2-enriched breast cancer did not vary by race or age. Among clinically HR-positive, HER2-negative cases, Luminal A subtype comprised only half of the cases among black women, and was significantly less common than among white women (51% vs 60% in whites, p&lt;0.05). Black women with HR-positive/HER2-negative disease also had significantly higher ROR scores (ROR-P medium or high 82% vs. 66% in whites, p=0.01; ROR-PT medium or high 85% vs. 69% in whites, p&lt;0.01).

Conclusions: Multi-gene assays highlight disparities in frequency of aggressive, poorer prognosis tumor subtypes and implicate differences in tumor biology as an important contributor to mortality disparities among HR-positive/HER2-negative patients.

Citation Format: Troester MA, Sun X, Allott EH, Kit C-K, Thorne L, Mathews M, Cohen SM, Geradts J, Kirk E, Li Y, Hu Z, Robinson W, Hoadley KA, Reeder-Hayes K, Earp S, Olshan AF, Carey LA, Perou CM. Race and age differences in PAM50 biomarker status in the Carolina breast cancer study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD8-01.

Persistence of levator ani sonographic defect detected by three-dimensional transperineal sonography in primiparous women

OBJECTIVES

Correlation of the sonographic appearance of levator ani muscle (LAM) injury soon after delivery with that at long-term follow-up has not been described fully. We aimed to compare results of three-dimensional (3D) transperineal sonographic (TPS) evaluation of the LAM from the period immediately postpartum with long-term follow-up, to determine whether sonographic findings persist over time.

METHODS

Primiparous women (n = 210) who had been examined by 3D-TPS in a previous study to determine LAM trauma 24-72 hours after delivery were invited to participate in a follow-up examination 3-21 months postpartum. We included in this study only women who were not pregnant when approached and who had not given birth in the interim. LAM trauma was diagnosed with 3D-TPS when we observed discontinuity and distortion of the most anteromedial part of the pubovisceral muscle in the coronal C-plane or rendered image. Initial and follow-up 3D-TPS results were compared using Cohen's kappa test for inter-rater agreement.

RESULTS

Among the 87 women included in this study we found strong correlation between earlier and later sonographic appearance of LAM: 17/21 women with a sonographic finding of LAM injury in the period immediately postpartum were positive in the follow-up examination, and only 2/66 women negative for LAM damage at the first examination were found to have sonographic evidence of LAM defect at follow-up (Cohen's kappa, 0.805 (95% CI, 0.656-0.954), P < 0.001).

CONCLUSIONS

Our findings suggest that 3D-TPS of the LAM is a reliable examination. A sonographic finding of LAM defect identified in the period immediately postpartum persists months or years after delivery; therefore, this test may be performed following delivery, or may be delayed without impacting the result. It is likely that this sonographic defect represents real anatomical disruption and is not an imaging artifact.

COMPRES: a prospective postmarketing evaluation of the compression anastomosis ring CAR 27(™) /ColonRing(™)

AIM

Preclinical studies have suggested that nitinol-based compression anastomosis might be a viable solution to anastomotic leak following low anterior resection. A prospective multicentre open label study was therefore designed to evaluate the performance of the ColonRing(™) in (low) colorectal anastomosis.

METHOD

The primary outcome measure was anastomotic leakage. Patients were recruited at 13 different colorectal surgical units in Europe, the United States and Israel. Institutional review board approval was obtained.

RESULTS

Between 21 March 2010 and 3 August 2011, 266 patients completed the study protocol. The overall anastomotic leakage rate was 5.3% for all anastomoses, including a rate of 3.1% for low anastomoses. Septic anastomotic complications occurred in 8.3% of all anastomoses and 8.2% of low anastomoses.

CONCLUSION

Nitinol compression anastomosis is safe, effective and easy to use and may offer an advantage for low colorectal anastomosis. A prospective randomized trial comparing ColonRing(™) with conventional stapling is needed.

Systematic examination of the fetal abdominal precordial veins: a cohort study

OBJECTIVES

Examination of the fetal venous system is a necessary part of complete fetal organ scanning to confirm landmark anatomy, such as the ductus venosus and course of the umbilical veins, and, whenever cardiovascular anomalies are identified, to exclude associated anomalous development of the fetal veins. We aimed to develop a protocol for systematic examination of the fetal venous system during midtrimester targeted organ scanning.

METHODS

We included low-risk women with a singleton fetus presenting between January 2011 and June 2013 to our center for routine midtrimester (20-24 weeks) targeted organ scanning. Imaging of the venous system was added to the booked scan and comprised two-dimensional color Doppler scanning of the fetal abdomen in three discrete planes, two transverse and one longitudinal. The more caudal plane was obtained in a ventral or lateral transverse abdominal plane to image the umbilical vein, left portal vein, portal sinus, anterior right portal vein, posterior right portal vein, main portal vein and splenic vein and artery. Moving cephalad, a ventral or lateral transverse plane was obtained to image the right, middle and left hepatic veins and inferior vena cava (IVC). Finally, a longitudinal anteroposterior plane showed the umbilical vein, ductus venosus, IVC and left hepatic vein. In some cases the pulsed Doppler waveform of a given target vessel was also examined. Three-dimensional/4D ultrasound was applied as necessary, when anomalous cases were encountered.

RESULTS

We examined 1810 women. Their body mass index ranged from 19 to 40 (mean, 24.7). In 38 (2.1%) women, the target anatomy was not visualized satisfactorily owing to maternal body habitus. A T-shaped configuration of the portal system vessels was observed in 63% of cases, an X-shaped configuration in 25% and an H-shaped configuration in 12%. During the study period, 24 congenital anomalies of the precordial venous system were diagnosed: nine cases of persistent right umbilical vein, seven of agenesis of the ductus venosus, five of anomalous portal venous drainage and three of interrupted IVC with azygos continuation.

CONCLUSIONS

Examination of the fetal venous system is feasible with the application of three abdominal planes. While a venous system scan is not practicable as part of a screening-level examination, mastery of the normal anatomy is an essential part of the professional knowledge base, in order to provide ready and complete scanning of the system in cases of suspected anomalies or disordered cardiac function.

Characterization of core-shell MOF particles by depth profiling experiments using on-line single particle mass spectrometry

Materials with core-shell structures have distinct properties that lend themselves to a variety of potential applications. Characterization of small particle core-shell materials presents a unique analytical challenge. Herein, single particles of solid-state materials with core-shell structures were measured using on-line aerosol time-of-flight mass spectrometry (ATOFMS). Laser 'depth profiling' experiments verified the core-shell nature of two known core-shell particle configurations (<2 μm diameter) that possessed inverted, complimentary core-shell compositions (ZrO2@SiO2 versus SiO2@ZrO2). The average peak area ratios of Si and Zr ions were calculated to definitively show their core-shell composition. These ratio curves acted as a calibrant for an uncharacterized sample – a metal-organic framework (MOF) material surround by silica (UiO-66(Zr)@SiO2; UiO = University of Oslo). ATOFMS depth profiling was used to show that these particles did indeed exhibit a core-shell architecture. The results presented here show that ATOFMS can provide unique insights into core-shell solid-state materials with particle diameters between 0.2-3 μm.

Sonographic finding of postpartum levator ani muscle injury correlates with pelvic floor clinical examination

OBJECTIVES

Correlation of the sonographic finding of levator ani muscle (LAM) injuries with clinical examination in primiparous women following vaginal delivery has not been fully described. We aimed to examine the correlation of three-dimensional transperineal ultrasound (3D-TPS) finding of LAM defects with results of clinical examination of the pelvic floor, at intermediate follow-up.

METHODS

Subjects were primiparae 3-21 months following vaginal delivery, who had not become pregnant or delivered in the interim. On 3D-TPS, LAM trauma was diagnosed when discontinuity and distortion were visible in the most anteromedial part of the pubovisceral muscle in the coronal C-plane or rendered image. Clinical examination was performed by a physiotherapist who was blinded to the ultrasound results, and included palpation of the medial and lateral parts of the LAM mass, evaluation of tissue quality and whether there was any palpable gap. Muscle strength was evaluated using the modified Oxford scale.

RESULTS

Eighty-seven women were included, 19 (21.8%) of whom were found to have a sonographic LAM injury. Oxford score palpation parameter of asymmetric muscle mass or texture was significantly correlated with the finding of a LAM defect: of 68 women with normal 3D-TPS, 22 (32.4%) were found to have asymmetry of muscle mass or tissue quality on clinical examination vs 12 (63.2%) of 19 women with sonographic evidence of LAM injury (P = 0.016). Muscle strength and endurance parameters did not significantly correlate with the 3D-TPS findings.

CONCLUSION

Our findings suggest that persistent 3D-TPS LAM injury after primary vaginal delivery has clinical expression in changes in mass and texture of the LAM, as assessed by palpation.

Fetal tricuspid annular plane systolic excursion (f-TAPSE): evaluation of fetal right heart systolic function with conventional M-mode ultrasound and spatiotemporal image correlation (STIC) M-mode

OBJECTIVES

Fetal tricuspid annular plane systolic excursion (f-TAPSE) is a modified method to measure the vertical movement of the tricuspid valve annulus by M-mode ultrasound, in order to assess the fetal right heart. Evaluation of right heart function is well-recognized in pediatric and adult cardiology, but has not been studied widely in the fetus. We aimed to study f-TAPSE in the second half of gestation in normal fetuses, to establish reference ranges for this measure, to evaluate the usefulness of spatiotemporal image correlation (STIC) M-mode in obtaining it, and to compare conventional M-mode and STIC M-mode-based measures of f-TAPSE.

METHODS

We recruited gravidae presenting to our centers from 20 to 38 weeks for targeted organ scans, fetal echocardiography or third-trimester fetal surveillance, with structurally normal singleton fetuses and verified gestational age (GA). Because of the small number of subjects at the lower limit, fetuses at 20 and those at 21 weeks were combined into a single group ('21 weeks'). During the booked scan, in addition to standard biometry, M-mode was applied to the tricuspid annulus, parallel to the ventricular septum, and the amplitude of the resulting wave was measured. To allow comparison with STIC M-mode, a STIC volume was acquired and saved. In post-processing, the volume was rotated to show an apical four-chamber view, and f-TAPSE was investigated in a similar fashion to that used for conventional M-mode. Two to three measures of TAPSE were taken and the results averaged. In thirty women, measurements were performed by two observers and inter- and intraobserver variation were calculated.

RESULTS

We examined 341 fetuses at GA 20-39 weeks. Conventional M-mode f-TAPSE values ranged from a mean of 3.6 (± 1.1) mm at 21 weeks to a mean of 8.6 (± 1.5) mm at 39 weeks. In 45 cases we were unable to perform conventional M-mode ultrasound because of fetal lie; in eight cases STIC volumes were found in post-processing to be unsuitable for analysis. STIC f-TAPSE values ranged from a mean of 4.2 (± 1.4) mm at 21 weeks to a mean of 8.3 (± 1.5) mm at 39 weeks. Scatterplots of f-TAPSE measures obtained with conventional M-mode and with STIC M-mode were created vs GA and estimated fetal weight (EFW). For both modalities, f-TAPSE increased linearly with GA and with EFW. Good correlation was found between the two methods (Pearson's R(2) = 0.904). No significant difference was found in mean or variance of the distributions or slopes of the regression equations. Inter- and intraobserver variation (intraclass correlation coefficient) in conventional M-mode and STIC M-mode f-TAPSE measures were 0.94 and 0.97, respectively.

CONCLUSION

F-TAPSE in normal fetuses increases over the course of gestation and correlates to EFW. F-TAPSE measurement is easy to perform and available on all ultrasound machines; STIC f-TAPSE is possible on machines with STIC capability and produces similar measures with a greater success rate. We suggest the addition of f-TAPSE measurement to fetal right cardiac function evaluation.

The fetal larynx and pharynx: structure and development on two- and three-dimensional ultrasound

OBJECTIVES

To present a systematic approach for evaluating the fetal pharynx and larynx based on two- and three-dimensional ultrasound (2D-US and 3D-US) modalities, describing the sonographic appearance and function of the fetal upper respiratory tract and measuring the anatomical components of the pharynx and larynx.

METHODS

Gravidae presenting from the late first trimester to mid-gestation for routine booked examinations with structurally normal singleton fetuses of confirmed gestational age were enrolled. Transabdominal 2D-US was performed for anatomical and functional evaluation of the pharynx and larynx. Color Doppler was used to show fluid motion in the target area. 3D-US (Voluson® E6 with RAB-4-8-D transducer) scans of the fetal neck were acquired during fetal quiescence and in the absence of movements of the pharynx and larynx. Multiplanar reconstruction (MPR) in post-processing allowed adjustment of the volume to obtain the coronal plane. After a learning period to understand the sonographic anatomy of the target area, we measured the pharynx width and height, the upper, middle and lower larynx width and the larynx height. Render mode was applied for spatial evaluation of the target area. We developed a new methodological approach for structured evaluation of the fetal pharynx and larynx based on five spatial planes: posterior and anterior coronal planes and high, mid and low axial planes.

RESULTS

We examined 582 fetuses during the second trimester of pregnancy; target anatomy was imaged successfully in 218 patients at 11-24 gestational weeks. Acquisition added approximately 1 min to examination time. Rates of successful visualization and measurements increased significantly as pregnancy progressed, being 23% (46/194) at 11-13 weeks, 29% (69/240) at 14-16 weeks, 35% (18/51) at 17-19 weeks and 88% (85/97) at 20-24 weeks (P < 0.01). Pharynx components identified were: the sphenoid bone, pterygoid processes, constrictor muscles, piriform recesses and uvula. Larynx components identified were: the epiglottis, aryepiglottic folds, corniculate cartilages, arytenoid cartilages, cricoid cartilage, thyroid cartilage and vocal cords. MPR showed the biconcave shape of the uvula, which may explain the 'equals sign' observed on 2D-US. We observed the bilateral mode of movements of the constrictor muscles, aryepiglottic folds and vocal cords, and the bidirectional fluid jet flows through the larynx. Scatterplots of measured structures vs gestational age were created. Pharynx width ranged from 0.11 to 0.93 (mean ± SD, 0.48 ± 0.17) cm; pharynx height ranged from 0.23 to 2.01 (mean ± SD, 0.94 ± 0.34) cm; upper larynx width ranged from 0.04 to 0.37 (mean ± SD, 0.15 ± 0.07) cm; middle larynx width ranged from 0.08 to 0.77 (mean ± SD, 0.34 ± 0.16) cm; lower larynx width ranged from 0.05 to 0.64 (mean ± SD, 0.24 ± 0.11) cm; and larynx height ranged from 0.20 to 1.83 (mean ± SD, 0.71 ± 0.31) cm. All measurements were positively correlated with gestational age.

CONCLUSIONS

The fetal larynx and pharynx can be evaluated thoroughly using 2D- and 3D-US modalities. Knowledge of normal anatomy, function and biometry may prove useful in the evaluation of anatomical or functional pathology involving the fetal upper respiratory tract. Recognition of anatomical anomalies may enhance fetal intervention such as balloon placement in cases of diaphragmatic hernia.

Functional assessment of the fetal heart: a review

The purpose of this review is to evaluate the current modalities available for the assessment of fetal cardiac function. The unique anatomy and physiology of the fetal circulation are described, with reference to the difference between in-utero and ex-utero life. M-mode, early/atrial ratio, myocardial performance index, three-dimensional and four-dimensional ultrasound, tissue Doppler including strain and strain rate, speckle tracking, magnetic resonance imaging and venous flow assessment are described. The modalities are analyzed from the perspective of the clinician and certain questions are posed. Does the modality assess systolic function, diastolic function or both? Is it applicable to both ventricles? Does it require extensive post-processing or additional hardware, or does it make use of technology already available to the average practitioner? The reproducibility and reliability of the techniques are evaluated, with reference to their utility in clinical decision-making. Finally, directions for future research are proposed.

Three-dimensional transperineal ultrasound findings associated with anal incontinence after intrapartum sphincter tears in primiparous women

OBJECTIVE

Three-dimensional transperineal sonography (3D-TPS) performed in women following third- or fourth-degree intrapartum tears repaired with the overlapping technique demonstrates characteristic signs. The aim of this study was to investigate the correlation of these signs with clinical complaints of incontinence.

METHODS

This was a prospective observational study. Sixty primiparous women underwent 3D-TPS 3-42 (mean, 10.6) months after surgical repair of third- or fourth-degree postpartum sphincter tears with the overlapping technique and were evaluated for clinical degree of incontinence using the St Mark's Incontinence Score (SMIS) questionnaire. The following signs were assessed on 3D-TPS: interruption of the internal anal sphincter or external anal sphincter, 'half moon' sign, changes in the mucosal folds and thickening of the external anal sphincter in the area of sphincter repair. As a comparison group, 27 primiparous women after normal vaginal delivery, without clinically recognized anal sphincter tears, were evaluated similarly, 3-37 (mean, 9.9) months postpartum.

RESULTS

Abnormal sonographic signs were apparent in 35 (58.3%) of 60 women in the study group, and 39 (65%) of 60 had some clinical complaints of incontinence 3-42 months after delivery, most of a mild degree. Higher SMIS results were found in women of the study group than in those of the comparison group (mean (SD) 2.80 (0.481) vs. 1.15 (0.365); P = 0.018). The rates of incontinence were similar between the women in the study group with normal ultrasound findings and the women in the comparison group (9/25 vs. 10/27; relative risk (RR) = 0.97, 95% CI, 0.47-1.97).

CONCLUSIONS

Sonographic signs of anal sphincter tear and repair had disappeared at follow-up examination in almost half of the patients, and therefore this examination should be deferred from the early postpartum period. A substantial proportion of women report some complaint of incontinence after sphincter repair, most of a slight degree. Such complaints are associated with abnormal 3D-TPS findings at follow up, while in women with a normal 3D-TPS scan the rate of incontinence complaints is similar to that in women after normal delivery.

Recurrent laryngopyocele: CT-guided hookwire localization for re-excision surgery

Laryngopyocele recurrence after initial surgical resection is a very rare occurrence. We present a case of recurrent laryngopyocele in which CT fluoroscopy-guided hookwire placement was used to facilitate resection. In this article, we illustrate the imaging findings of laryngopyocele, review the approach to management, and describe the CT fluoroscopy-guided hookwire placement procedure.

Fetal heart ventricular mass obtained by STIC acquisition combined with inversion mode and VOCAL

OBJECTIVE

Estimation of fetal heart ventricular mass is important for fetal cardiac evaluation in cases of structural or functional cardiac disorders or extracardiac factors. It may be used with other cardiac parameters to ascertain the severity and prognosis of such disorders, or the nature and timing of intervention. We applied a novel technique combining spatiotemporal image correlation (STIC) with three-dimensional inversion mode and Virtual Organ Computer-aided AnaLysis (VOCAL™) for fetal cardiac mass assessment in healthy fetuses in the second and third trimesters.

METHODS

STIC acquisition was performed during fetal quiescence with the abdomen uppermost, at an angle of 30-50°, without color Doppler mapping. Myocardial volume measurements were performed in postprocessing using VOCAL mode, set to 15°. Beginning with the heart in four-chamber view at end diastole, a trace was drawn manually including the myocardium and interventricular septum. Inversion mode colors the intraventricular (anechoic, fluid-filled) voxels; this intraventricular volume was subtracted automatically from the total. Mass was determined by multiplying the result by the estimated fetal myocardial density (1.050 g/cm(3) ). The process was repeated for right and left ventricles.

RESULTS

Data from 106 fetuses at 21-38 weeks' gestation were obtained and scatterplots of fetal cardiac ventricular mass distribution were created. Several cases of fetuses with disordered cardiac ventricle (supraventricular tachycardia, hypoplastic left heart syndrome, dilated cardiomyopathy, twin-to-twin transfusion syndrome, Ebstein anomaly, non-immune hydrops fetalis, septate right atrium and diaphragmatic hernia) were examined. Ventricular mass parameters were markedly affected as compared with normal cases of similar gestational age.

CONCLUSIONS

STIC acquisition combined with inversion mode and VOCAL is a feasible method of cardiac ventricular mass quantification. This methodology may have added value in fetal cardiac evaluation in cases of anatomic malformation or cardiac dysfunction, or in cases of maternal diabetes.

Added value of three-/four-dimensional ultrasound in offline analysis and diagnosis of congenital heart disease

OBJECTIVE

Many published studies have shown that application of three-dimensional (3D) and real-time 3D (4D) ultrasound modalities can improve certain aspects of fetal echocardiography, but have left open the question of whether these modalities improved the accuracy of prenatal detection of anatomical fetal cardiovascular malformations. We aimed to determine whether 3D/4D ultrasound improved diagnostic ability in cases of congenital heart disease (CHD).

METHODS

Women who attended for early- or midtrimester targeted organ scans had complete fetal echocardiography according to our five-planes protocol, as well as examination of the ductus venosus and longitudinal aortic arch planes, performed with 2D ultrasound combined with 2D color Doppler, spatiotemporal image correlation (STIC), STIC with color Doppler, and STIC with B-flow. Ultrasound data of cases of CHD were stored in a dedicated archive. Stored cases were anonymized and the list order was randomized. Stored 2D ultrasound cineloops and 4D ultrasound volumes were reviewed separately according to a standardized table of 23 specified structures on five required planes of visualization: the upper abdomen, four-chamber view, five-chamber view, pulmonary artery bifurcation view, and three vessels and trachea plane. Separate diagnoses were recorded and finally compared. Diagnoses were confirmed by pathological examination or neonatal echocardiography.

RESULTS

During the study period, 13 101 examinations were performed; 181 diagnoses of CHD were made. In 12 of these, 3D/4D ultrasound added to the accuracy of our diagnosis: one right aortic arch with anomalous branching; one transposition of the great arteries with pulmonary atresia diagnosed with tomographic ultrasound imaging (TUI); one segmental interrupted aortic arch diagnosed with TUI; one right ventricle aneurysm diagnosed with B-flow; two agenesis of ductus venosus to the coronary sinus diagnosed by multiplanar reconstruction (MPR) and B-flow; two total anomalous pulmonary venous connection diagnosed with MPR; and four ventricular septal defect (VSD) diagnosed with the aid of virtual planes. There were 12 missed diagnoses and no false-positive results.

CONCLUSIONS

3D/4D ultrasound modalities may have advantages in some aspects of fetal cardiovascular evaluation, however, overall 3D/4D ultrasound modalities had added value in only about 6% of cases of fetal anatomical cardiovascular anomalies.

Shunt diameter in agenesis of the ductus venosus with extrahepatic portosystemic shunt impacts on prognosis

OBJECTIVES

Agenesis of the ductus venosus (ADV) is a rare condition in which there are two variants of umbilical vein drainage: intrahepatic shunt or extrahepatic (portosystemic) shunt. It has been posited that the extrahepatic variant carries a poorer prognosis. However, in the absence of associated anomalies there is still a wide variation in outcome. We evaluated the portal system in cases of ADV and aimed to identify parameters that might predict outcome.

METHODS

We conducted a retrospective study of cases of ADV with extrahepatic shunt that had been examined in two centers, and collected new cases prospectively. The route of the shunt was depicted using two-dimensional (2D) and three-dimensional (3D) ultrasound imaging. In an attempt to characterize portal system and shunt developmental variations and their possible impact on outcome, the diameter of the shunt was compared with the diameter of the umbilical vein and the entire portal vasculature was assessed. Poor outcome was defined as persistent morbidity or fetal or neonatal death.

RESULTS

Twenty-two cases of ADV were identified: nine retrospectively and 13 prospectively. Aberrant shunts from the umbilical vein were identified to the right atrium, coronary sinus, inferior vena cava (IVC) and iliac vein. In seven of 22 cases (32%) a wide connection was observed. In six of these seven cases (86%) the outcome was poor, including four with severe associated anomalies and two with hepatic dysfunction. In five of these cases, cardiomegaly with tricuspid regurgitation was observed, as well as underdevelopment of the portal system. In only five of 15 cases with a narrow shunt (33%) was the outcome poor, and in all five cases the poor outcome was related to associated anomalies.

CONCLUSION

In cases of ADV with extrahepatic shunt, portal system development is impacted by the diameter of the shunt. If the shunt is narrow, the portal system will have developed normally. A wide shunt is associated with underdevelopment or absence of the portal system. In cases of ADV with extrahepatic shunt, prognosis is determined by the severity of associated anomalies, the diameter of the shunt and development of the portal system.

Added value of the gray-scale whirlpool sign in the diagnosis of adnexal torsion

OBJECTIVE

Adnexal torsion is a common gynecologic emergency affecting females of all ages. Expedient diagnosis and treatment are important, particularly in young fertile patients to preserve ovarian viability. Classical parameters for the clinical and sonographic diagnosis of adnexal torsion have very high false-positive rates, approaching 50%. The sonographic 'whirlpool' sign has been shown to be effective for visualizing the torsed part in the prenatal diagnosis of malrotation of the midgut with volvulus, as well as scrotal and ovarian torsion. We aimed to evaluate the efficacy of the whirlpool sign in the diagnosis of torsion, as compared to a protocol based on 'classic' sonographic signs of torsion alone.

METHODS

This was a retrospective chart review. Files of all patients who underwent laparoscopy for suspected torsion at our center between January 2006 and May 2009 were extracted and reviewed. Ultrasound reports were retrieved from our computerized database. Patients were assigned to the study group if the whirlpool sign had been investigated during pre-procedural evaluation or to the control group if only the standard protocol had been applied.

RESULTS

Eighty women were referred for laparoscopy for suspected adnexal torsion during the study period. In 22 women the ultrasound investigation had included the whirlpool sign (study group) while 58 had been examined by the standard protocol (control group). Twenty women in the study group had a positive whirlpool sign on ultrasound, 18 of whom (90.0%) had confirmed torsion on laparoscopy. In the control group 32 of 58 (55.2%) women had confirmed torsion on laparoscopy.

CONCLUSION

The addition of the sonographic whirlpool sign to the preoperative sonographic evaluation of patients with suspected torsion appears to improve the rate of true-positive diagnoses as confirmed by laparoscopy. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.

The fetal venous system, Part II: ultrasound evaluation of the fetus with congenital venous system malformation or developing circulatory compromise

The human fetal venous system is well-recognized as a target for investigation in cases of circulatory compromise, and a broad spectrum of malformations affecting this system has been described. In Part I of this review, we described the normal embryology, anatomy and physiology of this system, essential to the understanding of structural anomalies and the sequential changes encountered in intrauterine growth restriction and other developmental disorders. In Part II we review the etiology and sonographic appearance of malformations of the human fetal venous system, discuss the pathophysiology of the system and describe venous Doppler investigation in the fetus with circulatory compromise.

The fetal venous system, part I: normal embryology, anatomy, hemodynamics, ultrasound evaluation and Doppler investigation

Since its introduction in the mid-1980s sonographic evaluation of the human fetal venous system has advanced dramatically. The venous system is well-recognized as a target for investigation in cases of circulatory compromise, and a broad spectrum of malformations affecting this system has been described. Appreciation of the normal embryology, anatomy and physiology of this system is essential to an understanding of structural anomalies and the sequential changes encountered in intrauterine growth restriction or other developmental disorders. We review the normal embryology, anatomy, and hemodynamics of the human fetal venous system, and provide an overview of Doppler investigation, as well as three- and four-dimensional ultrasound modalities and their application to this system.

A case of myelodysplastic syndrome in a liver transplant patient

Although the incidence of (myelodysplastic syndrome (MDS)) is higher among heart and lung transplant recipients than the general population, the same has not been shown in liver transplant (OLT) patients. We present the second known case of MDS after OLT. Case reports of MDS in OLT were identified using PubMed. Patient data were gathered from the patient and the medical record. A 54-year-old Caucasian man underwent OLT in 2003 and again in 2004 for hepatitis C-related cirrhosis. In 2007, the patient developed weakness, malaise, and shortness of breath. Laboratory studies revealed pancytopenia. Bone marrow biopsy showed MDS, with refractory anemia and excess blasts-1. The patient underwent chemotherapy and reduction in immunosuppression without a clinical response. Our experience suggested that MDS, although rare, should be considered in the differential diagnosis of pancytopenia after OLT. Once diagnosed, immunosuppression reduction, chemotherapy, and even stem cell transplantation may be the appropriate treatment in selected candidates.

Review article: the diagnosis and management of alcoholic hepatitis

BACKGROUND

Alcoholic hepatitis is a severe, cholestatic liver disease occurring in patients with alcohol abuse. Mortality is substantial; however, therapies may improve clinical outcomes.

AIM

To provide an updated review of the epidemiology, diagnosis, staging and treatment of alcoholic hepatitis.

METHODS

A MEDLINE literature search was performed to identify pertinent articles. Relevant clinical abstracts were also reviewed.

RESULTS

Severe alcoholic hepatitis occurs in a small fraction of patients who abuse alcohol. The 28-day mortality ranges from 30% to 50% in most series. Diagnosis is generally based on clinical features, with a limited role for liver biopsy. Beneficial treatment options include alcohol abstinence and nutritional therapy. Despite variable results in clinical trials, corticosteroids and pentoxifylline appear to provide moderate survival benefit. Anti-tumour necrosis factor agents and antioxidants have not proven beneficial, and should be limited to clinical trials. Liver transplant is not a frequent option given the active or recent alcohol use.

CONCLUSIONS

Severe alcoholic hepatitis is a clinically-diagnosed condition associated with significant mortality. Alcohol abstinence and nutritional therapy have been associated with improved clinical parameters and should be considered in all patients. Corticosteroid therapy and pentoxifylline therapy appear to show moderate survival benefit and should be considered as first-line therapeutic agents.

Fetal cardiac ventricle volumetry in the second half of gestation assessed by 4D ultrasound using STIC combined with inversion mode

OBJECTIVE

Quantification of fetal heart ventricle volume can aid in the evaluation of functional and anatomical aspects of congenital heart disease. The aim of this study was to establish nomograms for ventricular volume using three-dimensional (3D) inversion mode ultrasonography with the spatio-temporal image correlation (STIC) modality and to calculate ejection fraction and stroke volume.

METHODS

The fetal heart was scanned using the STIC modality, during fetal quiescence with abdomen uppermost, at an angle of 30-50 degrees , without color Doppler flow mapping. In post-processing, starting with the classic four-chamber view plane in the A-frame, the reference point was moved to the center of the ventricle. The operator used the edit volume followed by Virtual Organ Computer-aided AnaLysis (VOCAL) mode options; in manual trace the VOCAL settings were set to 15 degrees . The trace was drawn and included the myocardium; inversion mode thresholding provided the volume of the intraventricular (anechoic) voxels within the region of interest. The total volume and the intraventricular volume were displayed. The process was repeated for right (R) and left (L) ventricles at end diastole (EDV) and end systole (ESV). The stroke volume (SV = EDV - ESV) and ejection fraction (EF = SV/EDV) were calculated from these measurements. Intraclass correlation was used to evaluate intra- and interobserver agreement.

RESULTS

One hundred fetuses ranging from 20 + 5 to 40 + 0 gestational weeks were included in the study. In addition, six fetuses diagnosed during the study period with a cardiac anomaly were examined and their ventricular volumes compared with those of the main study group. LEDV ranged from a mean of 0.53 cm(3) at midgestation to a mean of 3.96 cm(3) at term. LESV ranged from a mean of 0.17 cm(3) at midgestation to 1.56 cm(3) at term. REDV ranged from a mean of 0.68 cm(3) at midgestation to a mean of 5.44 cm(3) at term. RESV ranged from a mean of 0.26 cm(3) at midgestation to 2.29 cm(3) at term. Total stroke volume ranged from a mean of 0.78 cm(3) at midgestation to a mean of 5.5 cm(3) at term. The mean right : left ventricle ratio was 1.4, and left ejection fraction ranged from 42.5 to 86% in these fetuses. Nomograms were created for RESV, LESV, REDV, LEDV and total stroke volumes vs. estimated fetal weight and gestational age. Intra- and interobserver agreement reached 96%.

CONCLUSIONS

3D inversion mode sonography combined with STIC represents a simple and reproducible method for estimating fetal cardiac ventricle volume. This innovative methodology may add to overall evaluation of cardiac volume and function, and improve our understanding of normal and abnormal cardiac structure, as well as the severity and prognosis of cardiac lesions.

The FEMA GRAS assessment of aromatic substituted secondary alcohols, ketones, and related esters used as flavor ingredients

This publication is the 11th in a series of safety evaluations performed by the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA). In 1993, the Panel initiated a comprehensive program to re-evaluate the safety of more than 1700 GRAS flavoring substances under conditions of intended use. The list of GRAS substances has now grown to more than 2100 substances. Elements that are fundamental to the safety evaluation of flavor ingredients include exposure, structural analogy, metabolism, pharmacokinetics and toxicology. Flavor ingredients are evaluated individually and in the context of the available scientific information on the group of structurally related substances. In this monograph, a detailed interpretation is presented on the renal carcinogenic potential of the aromatic secondary alcohol alpha-methylbenzyl alcohol, aromatic ketone benzophenone, and corresponding alcohol benzhydrol. The relevance of these effects to the flavor use of these substances is also discussed. The group of aromatic substituted secondary alcohols, ketones, and related esters was reaffirmed as GRAS (GRASr) based, in part, on their rapid absorption, metabolic detoxication, and excretion in humans and other animals; their low level of flavor use; the wide margins of safety between the conservative estimates of intake and the no-observed-adverse effect levels determined from subchronic and chronic studies and the lack of significant genotoxic and mutagenic potential.

3D and 4D ultrasound in fetal cardiac scanning: a new look at the fetal heart

Over the last decade we have been witness to a burgeoning literature on three-dimensional (3D) and four-dimensional (4D) ultrasound-based studies of the fetal cardiovascular system. Recent advances in the technology of 3D/4D ultrasound systems allow almost real-time 3D/4D fetal heart scans. It appears that 3D/4D ultrasound in fetal echocardiography may make a significant contribution to interdisciplinary management team consultation, health delivery systems, parental counseling, and professional training. Our aim is to review the state of the art in 3D/4D fetal echocardiography through the literature and index cases of normal and anomalous fetal hearts.

Point mutation in codons 12 and 61 of the Ha-ras gene in rat urinary bladder carcinomas induced by N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide

Male F344 rats were fed N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) for up to 4 wk, then were given the basal diets (Prolab 3200 or AIN-76A) with or without 5% sodium saccharin for up to 100 wk. Eleven transitional cell carcinomas (TCCs), one undifferentiated carcinoma, and two sarcomas of the urinary bladder were examined for the expression of ras gene product, p21, by immunohistochemical staining and western blot analysis. Point mutation in codons 12 or 61 of the Ha-ras genes amplified by polymerase chain reaction was examined by a slot-blot screening procedure using allele-specific oligonucleotide probes. Immunohistochemical staining showed enhanced immunoreactivity with the antibody to ras p21 in seven TCCs and one undifferentiated carcinoma. Western blot analysis showed faster migration of the p21 band in 6 of 11 TCCs. Oligonucleotide hybridization revealed the point mutation in codon 12 of Ha-ras gene (GGA----GTA in 1 TCC) and in codon 61 (CAA----CGA in 5 TCCs and CAA----CTA in 1 TCC). Two mutations in codons 12 and 61 coexisted in one tumor, which were found to be present in different Ha-ras alleles. The incidence of Ha-ras gene mutations were similar in groups treated with (3 of 6) or without (3 of 8) sodium saccharin. These results suggest the involvement of activated Ha-ras gene in rat urinary bladder carcinogenesis induced by FANFT.

Rendering in fetal cardiac scanning: the intracardiac septa and the coronal atrioventricular valve planes

OBJECTIVE

In this study we aimed to apply spatio-temporal image correlation (STIC) rendering to visualize the virtual planes of the interventricular and interatrial septa (IVS, IAS) as well as the atrioventricular (AV) annuli plane just distal to the semilunar valves (coronal atrioventricular (CAV) plane) in normal and pathological fetal hearts, to ascertain whether these planes add to fetal cardiac examination.

METHODS

Unselected gravidae presenting for anatomy scan or patients referred for fetal echocardiography in the second and third trimesters of pregnancy with suspected or diagnosed cardiac malformation were scanned using the five planes technique with the STIC modality to obtain cardiac volume sets for each patient. Rendering capabilities were employed to obtain the 'virtual planes' to evaluate the IVS, IAS, AV annuli, and size and alignment of the great vessels.

RESULTS

A total of 136 normal scans were performed to establish a learning curve for STIC acquisition and post-processing rendering and analysis. An additional 35 cases with cardiac anomalies were accrued. In 131/136 (96.3%) normal scans the IAS and IVS were visualized successfully, while in 127/136 (93.4%) normal fetuses the CAV plane was successfully visualized. In 13 anomalous cases the IVS plane improved ventricular septal defect (VSD) evaluation, and in four the IAS plane contributed to foramen ovale evaluation. The modality improved visualization of the septa and the assessment of the defects, as well as the foramen ovale flap and pattern of movement of the foramen ovale. In five cases the CAV plane improved evaluation of the alignment of the major vessels in relation to the AV annuli, and in three the evaluation of the semilunar valves, with or without malalignment of the great vessels.

CONCLUSIONS

Rendering STIC technology allows the visualization of virtual planes (IAS, IVS, AV annuli-CAV plane), which can clarify our understanding of anatomical defects and may improve communication with the management team and family.

The FEMA GRAS assessment of benzyl derivatives used as flavor ingredients

This publication is the eighth in a series of safety evaluations performed by the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA). In 1993, the panel initiated a comprehensive program to re-evaluate the safety of more than 1700 GRAS flavoring substances under conditions of intended use. Elements that are fundamental to the safety evaluation of flavor ingredients include exposure, structural analogy, metabolism, pharmacokinetics and toxicology. Flavor ingredients are evaluated individually and in the context of the available scientific information on the group of structurally related substances. Scientific data relevant to the safety evaluation of the use of benzyl derivatives as flavoring ingredients is evaluated. The group of benzyl derivatives was reaffirmed as GRAS (GRASr) based, in part, on their self-limiting properties as flavoring substances in food; their rapid absorption, metabolic detoxication, and excretion in humans and other animals, their low level of flavor use, the wide margins of safety between the conservative estimates of intake and the no-observed-adverse effect levels determined from subchronic and chronic studies and the lack of significant genotoxic and mutagenic potential. This evidence of safety is supported by the fact that the intake of benzyl derivatives as natural components of traditional foods is greater than their intake as intentionally added flavoring substances.

The FEMA GRAS assessment of phenethyl alcohol, aldehyde, acid, and related acetals and esters used as flavor ingredients

This publication is the ninth in a series of safety evaluations performed by the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA). In 1993, the Panel initiated a comprehensive program to re-evaluate the safety of more than 1700 GRAS flavoring substances under conditions of intended use. Elements that are fundamental to the safety evaluation of flavor ingredients include exposure, structural analogy, metabolism, pharmacokinetics and toxicology. Flavor ingredients are evaluated individually and in the context of the available scientific information on the group of structurally related substances. Scientific data relevant to the safety evaluation of the use of phenethyl alcohol, aldehyde, acid, and related acetals and esters as flavoring ingredients is evaluated. The group of phenethylalcohol, aldehyde, acid, and related acetals and esters was reaffirmed as GRAS (GRASr) based, in part, on their self-limiting properties as flavoring substances in food, their rapid absorption, metabolic detoxication, and excretion in humans and other animals, their low level of flavor use, the wide margins of safety between the conservative estimates of intake and the no-observed-adverse effect levels determined from subchronic and chronic studies and the lack of significant genotoxic and mutagenic potential. This evidence of safety is supported by the fact that the intake of phenethyl alcohol, aldehyde, acid, and related acetals and esters as natural components of traditional foods is greater than their intake as intentionally added flavoring substances.

The FEMA GRAS assessment of hydroxy- and alkoxy-substituted benzyl derivatives used as flavor ingredients

This publication is the ninth in a series of safety evaluations performed by the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA). In 1993, the Panel initiated a comprehensive program to re-evaluate the safety of more than 1700 GRAS flavoring substances under conditions of intended use. Elements that are fundamental to the safety evaluation of flavor ingredients include exposure, structural analogy, metabolism, pharmacokinetics and toxicology. Flavor ingredients are evaluated individually and in the context of the available scientific information on the group of structurally related substances. Scientific data relevant to the safety evaluation of the use of hydroxy- and alkoxy-substituted benzyl derivatives as flavoring ingredients is evaluated. The group of hydroxy- and alkoxy-benzyl derivatives was reaffirmed as GRAS (GRASr) based, in part, on their self-limiting properties as flavoring substances in food; their rapid absorption, metabolic detoxication, and excretion in humans and other animals; their low level of flavor use; the wide margins of safety between the conservative estimates of intake and the no-observed-adverse effect levels determined from subchronic and chronic studies and the lack of significant genotoxic and mutagenic potential. This evidence of safety is supported by the fact that the intake of hydroxy- and alkoxy-substituted benzyl derivatives as natural components of traditional foods is greater than their intake as intentionally added flavoring substances.

A procedure for the safety evaluation of natural flavor complexes used as ingredients in food: essential oils

A scientifically based guide has been developed to evaluate the safety of naturally occurring mixtures, particularly essential oils, for their intended use as flavor ingredients. The approach relies on the complete chemical characterization of the essential oil and the variability of the composition of the oil in the product intended for commerce. Being products of common plant biochemical pathways, the chemically identified constituents are organized according to a limited number of well-established chemical groups called congeneric groups. The safety of the intake of the each congeneric group from consumption of the essential oil is evaluated in the context of data on absorption, metabolism, and toxicology of members of the congeneric group. The intake of the group of unidentified constituents is evaluated in the context of the consumption of the essential oil as a food, a highly conservative toxicologic threshold, and toxicity data on the essential oil or an essential oil of similar chemotaxonomy. The flexibility of the guide is reflected in the fact that high intake of major congeneric groups of low toxicologic concern will be evaluated along with low intake of minor congeneric groups of significant toxicological concern (i.e., higher structural class). The guide also provides a comprehensive evaluation of all congeneric groups and constituents that account for the majority of the composition of the essential oil. The overall objective of the guide is to organize and prioritize the chemical constituents of an essential oil in order that no reasonably possible significant risk associated with the intake of essential oil goes unevaluated. The guide is, however, not intended to be a rigid checklist. The Flavor and Extract Manufacturers Association (FEMA) Expert Panel will continue to evaluate each essential oil on a case by case basis applying their scientific judgment to insure that each natural flavor complex is exhaustively evaluated.

Safety evaluation of natural flavour complexes

Natural flavour complexes (NFCs) are chemical mixtures obtained by applying physical separation methods to botanical sources. Many NFCs are derived from foods. In the present paper, a 12-step procedure for the safety evaluation of NFCs, 'the naturals paradigm', is discussed. This procedure, which is not intended to be viewed as a rigid check list, begins with a description of the chemical composition of the commercial product, followed by a review of the data on the history of dietary use. Next, each constituent of an NFC is assigned to one of 33 congeneric groups of structurally related substances and to one of three classes of toxic potential, each with its own exposure threshold of toxicological concern. The group of substances of unknown structure is placed in the class of greatest toxic potential. In subsequent steps, for each congeneric group the procedure determines the per capita intake, considers metabolic pathways and explores the need and availability of toxicological data. Additional toxicological and analytical data may be required for a comprehensive safety evaluation. The procedure concludes with an evaluation of the NFC in its entirety, also considering combined exposure to congeneric groups. The first experiences with the use of this procedure are very promising. Future safety evaluations of larger numbers of NFCs will indicate the usefulness of the system, either in its present form or in a form modified on the basis of experience.

Urinary tract calculi and thresholds in carcinogenesis

Numerous chemicals administered to rodents at relatively high doses produce urinary tract calculi, resulting in erosions or ulcerations of the urothelium, consequent regenerative hyperplasia, and ultimately tumors. This is a high-dose (threshold) phenomenon, which appears to occur more readily in rodents than in primates, including humans. Several anatomic and urinary physiologic differences between rodents and humans affect the quantitative extrapolation from results in rodent bioassays to human risk assessment. For most chemicals producing tumors by this mode of action, human exposures are significantly lower than would be expected to be required for production of calculi, and therefore pose no carcinogenic hazard to humans.

Alternative models for carcinogenicity testing: weight of evidence evaluations across models

Twenty-one chemicals were evaluated by standardized protocols in 6 mouse models that have been sugggested as alternatives to the 2-year mouse bioassay. Included were genotoxic and nongenotoxic chemicals, carcinogens and noncarcinogens, immunosuppressive and estrogenic agents, peroxisome proliferators, and chemicals producing cancer in rodents by other mechanisms. Mice were sacrificed at the end of 6 to 12 months, depending on the model. Standardized histopathology, biostatistical analyses, and criteria for overall evaluation of the results were employed. The TgAC transgenic (dermal and oral administration), the Tg-rasH2 transgenic, the heterozygous p53 gene knockout, the homozygous XPA and homozygous XPA-heterozygous p53 gene knockout, and the neonatal mouse models were evaluated. The chemicals were also evaluated in the in vitro SHE assay. Comparison of the results between the various in vivo models suggest that they might have usefulness as screening bioassays for hazard identification for potential human carcinogens. They have the benefits of being quicker, less expensive, and involve fewer animals than the traditional 2-year mouse bioassay. They do not appear to be overly sensitive. However, they do not definitively distinguish between genotoxic and nongenotoxic carcinogens, and they do not have 100% specificity for identifying human carcinogens. Like the 2-year bioassay, the results from these models need to be evaluated in conjunction with other information on a chemical in an overall weight-of-evidence, integrated analytical approach to assess risk for human exposures.

Limb development: getting down to the ground state

In 1935, Snodgrass proposed that the evolutionary ground state of arthropod limbs consisted of two segments. Recent genetic studies on the Antennapedia and Homothorax genes of Drosophila raise questions about the nature of this ground state appendage.

Regulation of Apterous activity inDrosophilawing development

Apterous is a LIM-homeodomain protein that confers dorsal compartment identity in Drosophila wing development. Apterous activity requires formation of a complex with a co-factor, Chip/dLDB. Apterous activity is regulated during wing development by dLMO, which competes with Apterous for complex formation. Here, we present evidence that complex formation between Apterous, Chip and DNA stabilizes Apterous protein in vivo. We also report that a difference in the ability of Chip to bind the LIM domains of Apterous and dLMO contributes to regulation of activity levels in vivo.