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Objective: The aim of the study was to evaluate the performance of the first-trimester Fetal Medicine Foundation (FMF) screening algorithm, including maternal characteristics and medical history, blood pressure, pregnancy-associated plasma protein A and placenta growth factor, crown rump length, and uterine artery pulsatility index, for the prediction of preeclampsia in a high-risk population in the Netherlands. Methods: This is a prospective cohort including nulliparous women and women with preeclampsia or intrauterine growth restriction in previous pregnancy. We screened patients at 11–14 weeks of gestation to calculate the risk for preeclampsia. The primary outcome was preeclampsia and gestational age at delivery. Performance of the model was evaluated by area under the receiver operating characteristic (ROC) curves (AUCs) and calibration graphs; based on the ROC curves, optimal predicted risk cutoff values for our study population were defined. Results: We analyzed 362 women, of whom 22 (6%) developed preeclampsia. The algorithm showed fair discriminative performance for preeclampsia Conclusions: Performance of the FMF preeclampsia algorithm was satisfactory to predict early and preterm preeclampsia and less satisfactory for term preeclampsia in a high-risk population. However, by addressing some of the limitations of the present study, the performance can potentially improve. This is essential before implementation is considered.

Les descriptions de l’incidence, de la gravité et des modalités de prise en charge des blocs auriculoventriculaires du troisième degré (BAV3) compliquant la phase aiguë des infarctus du myocarde, avec sus-décalage du segment ST (STEMI), sont rares et anciennes. Par ailleurs, les modalités de prise en charge des STEMI aigus ont beaucoup évolué. Le but de notre étude est d’évaluer l’incidence, de décrire la gravité et les modalités de prise en charge des BAV3 survenant à la phase aiguë des STEMI dans un contexte contemporain. Matériel et méthodes : Nous avons réalisé une étude observationnelle rétrospective de la prise en charge des STEMI aigus à partir du registre prospectif des STEMI du Réseau nord alpin des urgences (RENAU) sur les 19 hôpitaux des Alpes du Nord entre 2009 et 2012. Les patients présentant un BAV3 à la phase initiale de leur prise en charge ont été identifiés. Résultats : Deux mille sept cent neuf patients avec STEMI aigu ont été inclus sur la période d’étude. Cinquante-sept ont présenté un BAV3 (2 %). Cent cinquante-deux des 2 648 patients sans BAV3 (6 %) sont décédés à la phase hospitalière contre 7 des 57 patients (12 %) avec BAV3 (p = 0,047). Parmi les patients en BAV3, un traitement par atropine a été utilisé pour 26 patients et s’est révélé efficace pour (15 %) d’entre eux. L’isoprénaline a été utilisée pour huit patients et a induit une hypotension artérielle pour quatre d’entre eux. Une stimulation ventriculaire droite percutanée a été utilisée pour six patients et a toujours été efficace. Quatorze patients ont été thrombolysés (25 %). Une angioplastie de sauvetage a été nécessaire chez 10 des 14 patients en BAV3 traités par thrombolyse (71 %), comparés aux 325 des 840 patients sans BAV3 traités par thrombolyse (39 % ; p = 0,013). Conclusion : L’incidence des BAV3 à la phase aiguë des STEMI est faible. Le BAV3 représente un facteur de sévérité. Les stratégies thérapeutiques sont d’efficacité inégale, avec des effets indésirables induits par l’isoprenaline. La thrombolyse chez ces patients est moins efficace.

Background Pseudofolliculitis barbae (PFB) significantly impacts the military population, especially deployed personnel. Objective This study was designed to determine whether the addition of topical eflornithine to hair laser treatment would improve efficacy in treating PFB. Methods This was a randomized, double-blinded, placebo-controlled, paired (right and left neck) comparison study examining a combination of eflornithine and hair laser versus placebo and hair laser for the treatment of PFB. In all, 27 male patients with clinical PFB were treated with a long-pulsed neodymium:yttrium-aluminum-garnet laser with an energy fluence of 25 to 30 J/cm 2 , a pulse duration of 20 to 30 milliseconds, and a 10-mm spot size to the entire bearded neck region. The laser treatment was performed every 4 weeks for a total of 16 weeks. Between laser treatments, patients applied eflornithine and placebo creams twice daily to opposite sides of the bearded neck region. The number of hairs and inflammatory papules were counted bilaterally at each visit. Results The eflornithine side had a statistically significant decrease in the number of hairs and inflammatory papules compared with the placebo side. At 16 weeks, the eflornithine side had a median hair reduction of 99.5% from baseline (range 48.5%-100.0%), whereas the placebo side had an 85.0% median hair reduction from baseline (range 50.5%-94.5%), P less than .001. Limitations Patients were not followed up beyond 16 weeks. Conclusion The addition of topical eflornithine to hair laser treatment decreased hairs and inflammatory papules faster when compared with hair laser therapy alone in the treatment of PFB.

Objective To evaluate volumetric changes of uterine myomas (fibroids) during pregnancy. Methods This was an observational, longitudinal and prospective study of 38 consecutive Caucasian women with singleton pregnancies and a total of 42 uterine myomas, enrolled from a cohort of 1492 women who took part in our first-trimester Down syndrome screening program. Myoma volume was evaluated by ultrasound at 11–14, 20–22 and 32–34 weeks of gestation. Results Mean myoma volume increased significantly throughout pregnancy. Taking a volumetric change of > 10% between gestational periods to be an increase in size, 71.4% of uterine myomas increased in size between the first and second gestational periods, while this percentage was slightly lower (66.6%) between the second and third periods. Logistic regression analysis revealed that greater maternal age was correlated with a reduction/no change in overall myoma size and multiparity was correlated with a decrease/no change between the first and second trimesters, while a higher prepregnancy maternal body mass index (BMI) was correlated with a volumetric increase between the first and second trimesters and a decrease/no change between the second and third trimesters. Conclusions Fibroids enlarge during pregnancy regardless of their initial size or local factors, and maternal age, prepregnancy BMI and parity are apparently correlated with these changes. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.

BACKGROUND A wide variety of materials present in current military conflict zones may be implanted and retained as "foreign bodies" or fragments in wounds. Analysis of removed fragments can be valuable to the patient, for research purposes, and for the protection of future potential victims. OBJECTIVES The objectives were to evaluate the composition of retained fragments in wounds from combat injuries and correlate this information with the mechanism of injury. METHODS Wound fragments from 10 U.S. military personnel wounded while deployed in Iraq for Operation Iraqi Freedom were removed from their skin and were subjected to gross examination, light microscopy, and scanning electron microscopy/energy-dispersive X-ray analysis (SEM-EDXA), with specimen radiography and infrared spectroscopy if indicated. RESULTS A variety of exogenous substances, including iron, lead, antimony, copper, aluminum, and acrylonitrile-styrene plastic were detected. No (depleted) uranium was detected. There was a high degree of correlation between the composition of the fragment removed and the wounding event. CONCLUSIONS Wound fragments may take months to years to manifest. Their gross appearance can be misleading. Establishing the composition of retained materials in wounds may assist in the clinical care of the wounded, provide forensic information, and have broader value in wound analysis and research.

The lack of data in the open literature on human exposure to the nerve agent O-ethyl-S-(2-diisopropylaminoethyl) methylphosphonothioate (VX) gives a special relevance to the data presented in this study in which we report the quantification of VX-butyrylcholinesterase adduct from a relatively low-level accidental human exposure. The samples were analyzed by gas chromatography-high resolution mass spectrometry using the fluoride ion regeneration method for the quantification of multiple nerve agents including VX. Six human plasma samples from the same individual were collected after the patient had been treated once with oxime immediately after exhibiting signs of exposure. Detection limits of approximately 5.5 pg/mL plasma were achieved for the G-analogue of VX (G-VX). Levels of the G-VX ranged from 81.4 pg/mL on the first day after the exposure to 6.9 pg/mL in the sample taken 27 days after the exposure. Based on the reported concentration of human butyrylcholinesterase in plasma of approximately 80 nM, it can be calculated that inhibition levels ofor= 0.05% of BuChE can be accurately quantified. These data further indicate that the fluoride ion regeneration method is a potentially powerful tool that can be used to assess low-level exposure to VX.

We report a new approach for assessing human exposure to bisphenol A (BPA) by measuring BPA in urine after enzymatic deglucuronidation. This method involves addition of (13)C(12)-labeled BPA, enzymatic deconjugation, solid-phase extraction, and derivatization with pentafluorobenzyl bromide. The product of the derivatization is separated by gas chromatography followed by mass spectrometric detection using negative chemical ionization and selected ion monitoring. Using this analysis method, urine samples fortified with both a constant level of labeled BPA and a range of unlabeled BPA levels (0.27-10.6 ng/ml) demonstrated constant percentage recovery. In addition, a range of urine sample volumes (0.25-10.0 ml) with constant amounts of added internal standard produced a linear response (r(2)=0.99). The method limit of detection was 0.12 ng/ml. This method was validated by duplicate analyses using gas chromatography coupled to a high-resolution mass spectrometer.

We developed a sensitive and accurate analytical method for quantifying methyleugenol (ME) in human serum. Our method uses a simple solid-phase extraction followed by a highly specific analysis using isotope dilution gas chromatography-high resolution mass spectrometry. Our method is very accurate; its limit of detection is 3.1 pg/g and its average coefficient of variation is 14% over a 200-pg/g range. We applied this method to measure serum ME concentrations in adults in the general U.S. population. ME was detected in 98% of our samples, with a mean ME concentration of 24 pg/g (range < 3.1-390 pg/g). Lipid adjustment of the data did not alter the distribution. Bivariate and multivariate analyses using selected demographic variables showed only marginal relationships between race/ethnicity and sex/fasting status with serum ME concentrations. Although no demographic variable was a good predictor of ME exposure or dose, our data indicate prevalent exposure of U.S. adults to ME. Detailed pharmacokinetic studies are required to determine the relationship between ME intake and human serum ME concentrations. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Aim To estimate the incidence of preeclampsia (PE) among nulliparous and multiparous patients with type 1 diabetes and to study predictors of PE. Methods We prospectively collected data on all pregnancies of patients with pregestational type 1 diabetes, followed at our Prenatal Medicine Unit between 1993 and 2008. Medical records were prospectively reviewed by two obstetricians for maternal demographics, pregnancy data, maternal and fetal outcomes. Data were analyzed according to the development of PE and parity. Results We identified and collected data on 291 eligible pregnancies (195 among nulliparae and 96 among multiparae). The incidence of PE was 9.2% (95% CI: 5.6–14.2) among nulliparae and 9.4% (95% CI: 4.4–17.0) among multiparae. Patients who developed PE had higher HbA1c during pregnancy compared to patients who did not ( p =0.026 among nulliparae and p =0.032 among multiparae). Chronic hypertension [OR 17.12 (3.22, 91.00)], microalbuminuria at the beginning of the pregnancy [OR 3.77 (1.22, 11.61)], weight gain during pregnancy [OR 1.13 (1.04, 1.23)] and HbA1c in the first trimester [2.81 (1.12, 7.05)], but not parity, were significant predictors of PE. Conclusions Among patients with type 1 diabetes the incidence of PE was similar among nulliparae and multiparae, unlikely in the general population where PE is a disease of the first pregnancy. An increased risk of PE should be assumed for both nulliparous and multiparous women with pregestational diabetes.

The impact of hypertension in the pregnancies from autoimmune patients is not unequivocally defined. We have prospectively followed 168 pregnancies from 135 patients from four Italian centres to verify the potential impact of hypertension in the antiphospholipid syndrome (APS). The rate of preeclampsia, mean neonatal weight and gestational age at delivery were significantly lower in patients with both APS and hypertension than in patients with hypertension or APS alone. This information may be relevant for counselling and care of these patients.

We have measured non-ortho-substituted (coplanar) polychlorinated biphenyl (PCB) levels as well as polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzofuran (PCDF) levels in human adipose tissue and serum collected in Atlanta, Georgia. The results show that the concentrations of the coplanar PCBs can be more than an order of magnitude higher than the concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin. Our measurements in pooled serum collected in 1982, 1988, and 1989 show a decrease in coplanar PCB levels from 1982 to 1989. We found that the pattern of relative amounts of coplanar PCBs in adipose tissue varied greatly from person to person unlike the PCDD and PCDF patterns, which were more nearly the same. Age was significantly correlated with the concentrations of 2,3,7,8-TCDD,3,3'4,4'-PCB, 3,3',4,4',5-PCB, and 3,3'4,4',5,5'-PCB in adipose tissue. We also measured levels of the mono- and di-ortho chlorine-substituted PCBs in human serum. The levels for some of these PCB congeners were three orders of magnitude higher than the coplanar PCBs, PCDDs, and PCDFs. We used the international toxicity equivalency factors (TEFs) for PCDDs and PCDFs and the TEFs proposed by Safe for PCBs to calculate the 2,3,7,8-TCDD equivalents. Four PCBs (3,3',4,4',5-; 2,3',4,4',5-;2,3,3',4,4'-;2,3,3',4,4',5-) make a larger contribution than 2,3,7,8-TCDD, while four other PCBs (3,3',4,4'5,5'-; 2,2',3,4,4',5'-;2,2',4,4',5,5'-;2,2',3,4,4',5,5'-) make nearly the same contribution as 2,3,7,8-TCDD. The mono-ortho-chlorine-substituted 2,3',4,4',5-PCB, however, is the major contributor to the total 2,3,7,8-TCDD equivalents in general population samples from the United States, Sweden, and Japan.(ABSTRACT TRUNCATED AT 250 WORDS)

It has been reported that the reninangiotensin- aldosterone system of healthy newborn infants and pre-term infants responds to acute furosemide challenge.To assess urinary aldosterone excretion (UAE) and electrolytic balance in very low-birth weight (VLBW) infants who received chronic therapy with furosemide and to compare them with those of infants who did not receive diuretic therapy.Infants with birth weight1500 g were considered eligible for this prospective observational study. On the 10th day of life, infants enrolled were divided in 2 groups on the basis of our predictive score for chronic lung disease (CLD): group 1, with positive score, received furosemide and group 2, with negative score, did not receive diuretic therapy. Urinary aldosterone and electrolytes excretion, electrolytes intakes and clearance of creatinine were investigated before the beginning of the treatment and then weekly until discharge in both groups, and results were compared.Thirty infants were studied: 15 received long-term furosemide and 15 did not. UAE progressively increased in infants who received furosemide whereas remained unchanged in infants who did not receive treatment. UAE was greater in group 1 than in group 2 after 3 weeks of diuretic treatment, reaching statistical significance after 4 weeks of treatment.In VLBW infants, chronic therapy with furosemide leads to a progressive increase in UAE that may potentially limit the diuretic effect of long-term use of furosemide in the management of CLD.

To evaluate volumetric changes of uterine myomas (fibroids) during pregnancy.This was an observational, longitudinal and prospective study of 38 consecutive Caucasian women with singleton pregnancies and a total of 42 uterine myomas, enrolled from a cohort of 1492 women who took part in our first-trimester Down syndrome screening program. Myoma volume was evaluated by ultrasound at 11-14, 20-22 and 32-34 weeks of gestation.Mean myoma volume increased significantly throughout pregnancy. Taking a volumetric change of10% between gestational periods to be an increase in size, 71.4% of uterine myomas increased in size between the first and second gestational periods, while this percentage was slightly lower (66.6%) between the second and third periods. Logistic regression analysis revealed that greater maternal age was correlated with a reduction/no change in overall myoma size and multiparity was correlated with a decrease/no change between the first and second trimesters, while a higher prepregnancy maternal body mass index (BMI) was correlated with a volumetric increase between the first and second trimesters and a decrease/no change between the second and third trimesters.Fibroids enlarge during pregnancy regardless of their initial size or local factors, and maternal age, prepregnancy BMI and parity are apparently correlated with these changes.

The synthesis of (±)-[1,1′-15N2, 2′-13C]-trans-3′-methylnicotine is reported. 15N-3-Bromopyridine obtained from bromination of pyridine was formulated with nBuLi/[carbonyl-13C]-methyl formate. The resulting 15N-Pyridine-3-[13C-carbonyl]-carboxaldehyde was reacted with 15N-methylamine and then the resulting Schiff's base was condensed with succinic anhydride to give (±)-[1,1′-15N2, 5′-13C]-trans-4′-carboxycotinine. Reduction with lithium aluminium hydride and mesylation followed by reduction with Zn/Nal gave (±)-[1,1′-15N2, 2′-13C]-trans-3′-methylnicotine.

The aim of the study was to compare a group of very low birth-weight infants feeded with a preterm formula with two other groups feeded with human milk and two different fortifiers.30 preterm newborns with birth-weight1.500 g, admitted to the Neonatal Intensive Care Unit (NICU) of Department of Neonatology of Catholic University of Rome were randomized for three different feeding groups: total enteral nutrition with HM fortified with Enfamil Human Milk fortifier or with Eoprotin, compared to a group feeded with Similac 24 preterm formula. Statistical analysis was performed using the two-way analysis of variance (ANOVA).During the study and at the end we found a growth rate for weight, cranial circumference and lenght similar to the fetal standard growth rate in the third trimester of pregnancy in all the three groups. Fortified HM was well tolerated. No pathologic value of the biochemical parameters studied was found. Higher level of serum phosphorus in spite of significantly lower intakes of phosphorus occurred in fortified HM feeded neonates, as if there was a better availability of this nutrient in HM.This study demonstrates the role of fortified HM as a good alternative to the preterm formula.

Because human toxaphene exposure data are largely lacking, we surveyed human serum pools collected from U.S. residents to determine the feasibility of measuring toxaphene in human samples and to determine whether additional analytical requirements were needed for routine measurement of toxaphene. We report a method for quantification of toxaphene congeners in human serum using a mixed-bed gradient solid-phase extraction and analysis using gas chromatography–high-resolution mass spectrometry with electron-impact ionization. In this method, we monitored low-mass fragment ions that were common to all 22 congeners. To verify the specific congeners detected, we further analyzed the extract using negative methane chemical ionization. We used this method to measure two specific congeners, Parlar 26 and 50, at concentrations ranging from about 3 to 30 pg/ml (0.7−7 ng/g lipid) in pooled human serum collected in Atlanta, Chicago, and Cincinnati. We identified several analytical parameters that must be strengthened to routinely measure toxaphene congeners in human samples.

One of the most appropriate biomarkers for the verification of organophosphorus nerve agent exposure is the conjugate of the nerve agent to butyrylcholinesterase (BuChE). The phosphyl moiety of the nerve agent can be released from the BuChE enzyme by incubation with fluoride ions, after which the resulting organophosphonofluoridate can be analyzed with gas chromatography-mass spectrometry (GC-MS). This paper describes recent improvements of the fluoride-induced reactivation in human plasma or serum samples by enhancing the sample preparation with new solid-phase extraction cartridges and the MS analysis with large volume injections. Analysis is performed with thermal desorption GC with either mass selective detection with ammonia chemical ionization or high-resolution MS with electron impact ionization. The organophosphorus chemical warfare agents analyzed in this study are O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate, ethyl methylphosphonofluoridate, isopropyl methylphosphonofluoridate (sarin, GB), O-ethyl N,N-dimethylphosphoramidocyanidate, ethyl N,N- dimethylphosphoramidofluoridate, and cyclohexyl methylphosphonfluoridate. Detection limits of approximately 10 pg/mL plasma were achieved for all analytes, which corresponds to 0.09% inhibition with GB on a sample with normal BuChE levels.

To increase our analytical throughput for measuring polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides without sacrificing data quality, we have developed and validated a combined PCB/OC pesticide gas chromatography-high-resolution mass spectrometry (GC-HRMS) analysis. In a single GC-HRMS analysis, both selected PCBs and OC pesticides are detected and quantified. Previously, this has been difficult, if not impossible, because of the major difference in masses of the most abundant electron-impact ions. However, we have identified slightly less abundant ions to monitor that allow us to successfully combine these analytes into a single analysis without sacrificing any analytical sensitivity or instrument reliability. Consequently, we have been able to double our analytical throughput by modification of mass spectrometric parameters alone. Our new methodology has been validated against our current GC-HRMS method, which entails using two separate injections, one for PCB analysis and one for OC pesticide analysis. The two methods differ by less than 4% overall, with no systematic bias. We used this method to analyze approximately 350 serum samples over a period of several months. We found that our new method was as reliable in automated, overnight runs as our current method.

The Centers for Disease Control and Prevention (CDC) is involved in many epidemiological studies regarding the measurement of chlorinated pesticides and polychlorinated biphenyls in specimens obtained from humans. In addition to these commonly determined analytes, there is a need to include additional persistent organic pollutants (POPs) in our analyses, which further stresses the analyses because sample volumes remain small. Thus, a single method of analysis for all POPs in human serum is needed. CDC has recently developed a semiautomated and comprehensive solid-phase extraction method for POPs. The method is comprehensive since it was optimized for the extraction of many different POP compound classes. We then developed a purification and fractionation scheme that allows (a) separation of different compound classes by particular functionalities and (b) purification of those fractions to remove coextracted interferences. This paper describes the first step in the semiautomated comprehensive extraction and multiple fractionation method developed by CDC for monitoring POPs. In this paper, we validate the analysis of the persistent chlorinated pesticides, a compound class difficult to examine because of their structural diversity, in human plasma. The method was validated against an existing CDC method by using a spiked quality-control serum pool. The concentrations determined for all analytes using both methods were within 2%-14% relative standard deviations. A multilevel (i.e., 3-4 point) matrix spike showed good linearity for the analytes tested (r2 = 0.978-0.999). The method was then applied to 40-year-old archived plasma samples for the quantitative analysis of selected chlorinated pesticides. Mean recoveries of the 13C-labeled internal quantification standards ranged from 64% to 123% for the 11 monitored pesticides. The overall method proved to be robust by handling old coagulated plasma samples. It allowed faster throughput of samples than our previous methods and provided cleaner samples with less frequent interferences or background as analyzed by high-resolution mass spectrometry. The method represents a preliminary step in establishing an automated, comprehensive multiresidue analysis method for POPs in human serum.

We have developed a sensitive and accurate analytical method for quantifying 29 contemporary pesticides in human serum or plasma. These pesticides include organophosphates, carbamates, chloroacetanilides, and synthetic pyrethroids among others and include pesticides used in agricultural and residential settings. Our method employs a simple solid-phase extraction followed by a highly selective analysis using isotope dilution gas chromatography–high-resolution mass spectrometry. Our method is very accurate, has limits of detection in the low pg/g range and coefficients of variation of typically less than 20% at the low pg/g end of the method linear range. We have used this method to measure plasma pesticide concentrations in females living in an urban area. We found detectable concentrations of carbaryl/naphthalene, propoxur, bendiocarb, chlorpyrifos, diazinon, dicloran, captan and folpet or their metabolites in more than 20% of the plasma samples tested.

A randomized study was designed to evaluate the effects of two different dexamethasone courses on the growth of preterm infants. The first phase included 30 preterm infants at high risk for chronic lung disease (CLD). 15 babies (moderately early dexamethasone group) were treated with dexamethasone for 14 days, from the 10th day of life, and received a total dose of 4.75 mg/kg; 15 babies were assigned to the control group. The second phase included 30 preterm infants at high risk for CLD. 15 babies (early dexamethasone group) were treated with dexamethasone for 7 days, from the 4th day of life, and received a total dose of 2.38 mg/kg; 15 babies were assigned to the control group. All the main clinical baseline characteristics were similar between the groups both in the first and in the second phase. Infants given the two dexamethasone courses showed significantly reduced weight gain during the period of treatment when compared to the respective control group, but they had a weight catch-up soon after the end of treatment. At 30 days of life the weight and length gain of each treated group were similar to those of control infants, but the moderately early dexamethasone group showed a significantly poorer head growth. No differences between the groups were observed at discharge. Dexamethasone treatment induces a slower weight gain which is time-limited to the period of treatment and is followed by a body weight catch-up. However, the poorer head growth detected at 30 days of life in the infants who received a higher dose of dexamethasone could indicate important adverse effects, possibly dose-related, on postnatal brain growth and development.

Citrobacter rodentium from an undetermined source was detected in a breeding colony of T-cell receptor transgenic mice housed in a conventional mouse facility in which murine hepatitis virus had been endemic and Helicobacter spp. had been detected. Citrobacter rodentium, isolated from blood, spleen, and colon, correlated with a significant increase in mortality and morbidity in this breeding colony. Transgenic mice of all ages were affected by chronic debilitation, loss in reproductive efficiency, rectal prolapse, and acute death, resulting in the near loss of these noncommercially available strains. Several alterations in immunologic parameters were observed, including outgrowth of an unusual population of cells in the spleen and blood, reduction in ascites production, loss of the capacity of peritoneal exudate cells to serve as feeders for the cloning of long-term T-cell lines, and inhibition of antigen-specific cytotoxic T-cell activity. These altered immune functions also were apparent in commercially-derived nontransgenic mice cohoused with the infected colony and in overtly healthy transgenic and nontransgenic littermates. Citrobacter rodentium and murine hepatitis virus were eliminated ultimately on rederivation of the affected strains by embryo transfer. However, the rapid decrease in the health of the colony necessitated more immediate action. To reduce mortality and allow breeding to continue during rederivation of the transgenic lines, animals were treated with enrofloxacin and moved to a barrier facility. Antibiotic therapy significantly reduced morbidity and mortality, markedly increased litter size and frequency, and resulted in the normalization of many of the immunologic assays. The involvement of C. rodentium in altering viability of the colony and perturbing immunologic assays is suggested by correlation of the onset of the syndrome with the appearance of Citrobacter sp. and its resolution with the elimination of Citrobacter sp. from the colony. Whether infection with Citrobacter alone is causative or whether superinfection of murine hepatitis virus- and Helicobacter-infected mice is required remains to be determined.

Exogenous retinoic acid is teratogenic in animals and man, causing a spectrum of abnormalities termed retinoic acid embryopathy. Using a mouse model of retinoic acid embryopathy, our results show that exposure to all-trans retinoic acid (RA) on gestational day (gd) 9 results in thymic ectopia, hypoplasia, and thymocyte maturational defects. Immunohistochemical and flow cytometric analyses showed aberrant expression of stromal and thymocyte markers, and abnormalities in thymocyte development. RNA in situ hybridization for the transcription factors Hoxa3 and Pax1 was used to investigate the basis of this defect. Hoxa3 and Pax1 have been shown to be required for normal thymus development, and are normally expressed in the cells of the third pharyngeal pouch and third and fourth pharyngeal arches, involved in thymus organogenesis RA-exposed embryos showed an increased level of Hoxa3 expression in the neural tube and caudal pharyngeal arches as soon as 6 hr after exposure. The Pax1 expression pattern, in conjunction with analysis of the external pharyngeal morphology, showed that the development and structure of the third pharyngeal pouch and cleft were disrupted, resulting in a reduced third pharyngeal arch and/or fusion of the third and fourth arches. Changes in the expression of cellular retinoic acid binding protein (CRABP) and in the morphology of the cranial ganglia were consistent with altered neural crest cell migration from the caudal hindbrain after RA exposure. Together, our findings suggest that the teratogenic effects of RA on thymus development include changes in both the cranial neural crest and pharyngeal endoderm that contribute to thymus development. Further, the observed defects in thymus development may be mediated by RA-induced alterations in the expression of Hoxa3.

Olefins such as isobutylene and styrene can be cationically polymerized in a controlled/living fashion under certain specific conditions. The best systems tend to employ either TiCl4 or BCl3 coinitiators. Lewis base additives are used to suppress both protic initiation and propagation by free ions. The growing chains are characterized by a reversible ionization equilibrium between a small concentration of active ion pairs and a much larger concentration of dormant chains. These systems deviate from ideal living behavior to a lesser or greater degree depending upon conditions. With select systems at low temperatures, the deviations are very small, and well defined polymers can be produced. Non-ideality results from unimolecular termination reactions, as opposed to bimolecular chain transfer to monomer. This makes clear the danger of excess aging of living chains, and it highlights the practical importance to synthetic procedures of a thorough understanding of the kinetics of propagation and chain breaking events.

The pharmacokinetics of 2 doses of intravenous ketorolac (0.5 and 0.9 mg x kg-1) were studied in 14 children (age 2-8 years). A single dose of the drug was injected into the dorsum vein of one hand. Blood samples were collected at regular time intervals for 6 hours. Serum ketorolac concentrations were assayed using a high pressure liquid chromatography method. Pharmacokinetic values were estimated by a nonlinear computer program. The distribution volume (Vdarea), the total clearance (Cltotal), and elimination half-life (t1/2 beta) were similar in both groups of children who either received 0.5 or 0.9 mg x kg-1 of ketorolac. The estimated geometric mean Vdarea, Cltotal, and t1/2 beta ratios (95% CI in parentheses) for 0.9 mg x kg-1:0.5 mg x kg-1 were 1.24 (0.82, 1.50), 1.14 (0.88, 1.23), and 1.083 (0.40, 1.81), respectively. The pharmacokinetic parameters found in this study are different from those found by other authors in adult subjects.

The authors report their experience in the Division of Neonatology of the Catholic University of Rome about the choice of milk alimentation and mineral and vitamin supplementation before discharge and during the subsequent follow-up, with particular reference to very low-birthweight preterm infants (1500 g). Basing on empirical experiences, the authors emphasize the importance in current practice of post-conceptional age, with special regard to the kind of milk to choose after discharge and the time and terms of the weaning. Furthermore they stress nutritional, immuno-allergic and psychological advantages of human milk before and after hospital discharge, particularly related to the presence of long-chain polyunsaturated fatty acid (LCP), recently known to be essential on retina and brain development in the preterm infant. When breast milk is not available, the authors confirm the efficacy, before discharge, of preterm infant formulas and subsequently of infant formulas and after of follow-up formulas. The authors hope that the directions proposed by the American Academy of Pediatrics in 1983 will be modified in order to recommend cow-milk only after the first year of life of the infant. They finally suggest specific mineral and vitamin supplementations (iron, calcium, phosphorus, fluoride; vitamins K, D, E and folic acid), to be started after hospital discharge.

Retinoic acid is known to perturb craniofacial development and can be used to understand processes controlling early embryonic development of the face. The effects of retinoic acid on mouse craniofacial development were studied by administration of a single dose (25-200 mg/ kg) of all-trans retinoic acid (RA) to timed pregnant C57BL6/J mice at gestational days (gd) 8.25, 9, or 10. RA exposure on gd 8.25 or gd 10 resulted in craniofacial defects in fetuses but gd 9 exposure revealed a differential effect of RA depending upon whether tissues were derived from branchial arch or frontonasal neural crest. Embryos exposed to RA at gd 9 showed a dose-dependent effect of RA on branchial arch derived tissues; first arch derivatives were most severely affected with the mandible and zygoma becoming severely dysplastic at the highest dose of RA (200 mg/kg). However, RA exposure on gd 9 completely spared frontonasal neural crest-derived tissues. Paired premaxillae nasal and frontal bones as well as the cartilaginous nasoethmoid region and nasal capsule containing the osseous vomer showed no statistical difference from those of control animals. These studies showed a temporal and differential sensitivity to RA and may suggest a developmental heterogeneity of the cephalic neural crest cells destined to participate in formation of craniofacial structures.

An enzymatic hydrolysis isotope dilution-mass spectrometric method was developed for reference quantification of specific proteins. The analytical procedure involved measuring a reproducibly hydrolyzed peptide (serving as the primary standard) unique to a specific protein. This new mass spectrometric method was evaluated by assessing the concentration of apolipoprotein (apo) A-I in the European Community Bureau of Reference (BCR) lyophilized Certified Reference Material (CRM 393). We used the method to make 96 measurements (4 replicate analyses of 4 enzymatic digests of 6 vials of BCR-CRM 393), which gave an average total protein mass of 1.048 mg (+/- 1.0% at 99% confidence limits). The total overall analytical CV was 3.95%. The results of this evaluation of our model approach to determine the concentration of a specific protein in a purified preparation demonstrated that our new mass spectrometric method can be used to measure apolipoproteins and other specific proteins without the use of epitopic immunoassay methods.

Reversed-phase liquid chromatographic fractions of extracts of 2 preparations of eosinophilia-myalgia syndrome (EMS)-associated L-tryptophan were analyzed by proton nuclear magnetic resonance spectrometry, mass spectrometry, microbial-growth inhibition, and amino acid residue analyses. Fraction components demonstrated properties of an antibiotic peptide resembling bacitracin. Many peptide antibiotics like bacitracin are secondary metabolites of Bacillus species, genus of the tryptophan producer organism for the implicated manufacturer. In order to determine whether a correlation exists between individual EMS cases and the concentration of peptides or bacitracin consumed, reliable methods must be developed for quantification of the total of isoforms.