Molecular and behavioral toxicity assessment of tiafenacil, a novel PPO-inhibiting herbicide, in zebrafish embryos/larvae.

Tiafenacil is a newly registered herbicide and a protoporphyrinogen IX oxidase inhibitor. However, sub-lethal effects of PPO-inhibitors in aquatic species are unknown. Embryos or larvae were exposed to 0.1 µg/L up to 10 mg/L tiafenacil for 7-days post-fertilization. Decreased survival (> 50%) and deformities were noted at concentrations > 1 mg/L. Potency (EC50) of tiafenacil for 5- and 7-day larvae were 818.1 µg/L and 821.7 µg/L, respectively. Pericardial and yolk sac edema were the most frequent deformities observed. Heartbeat frequency at 3 dpf was decreased in zebrafish exposed to > 10 µg/L tiafenacil, coinciding with increased reactive oxygen species. Oxygen consumption rates were not affected by tiafenacil, nor did we detect differences in indicators of apoptosis. The abundance of eighteen transcripts related to oxidative stress and mitochondrial complexes I through V were unchanged. Larval activity was decreased with exposure to 1000 µg/L tiafenacil. These data contribute to risk assessment for a new class of herbicide.

Down-regulation of complement genes in lipopolysaccharidechallenged zebrafish (Danio rerio) larvae exposed to Indonesian propolis / Regulação negativa dos genes do complemento em larvas de peixe-zebra (Danio rerio) desafiadas com lipopolissacarídeo expostas à própolis indonésia

Although propolis has been reported for having anti-inflammatory activities, its effects on complement system has not been much studied. This research was conducted to find out the effects of Indonesian propolis on the expression levels of C3, C1r/s, Bf, MBL, and C6 in zebrafish larvae which were induced by lipopolysaccharide (LPS). Counting of macrophages migrating to yolk sac and liver histology were carried out. Larvae were divided into four groups: CON (cultured in E3 medium only), LPS (cultured in a medium containing 0.5 μg/L LPS), LPSIBU (cultured in a medium containing LPS, and then treated with 100 μg/L ibuprofen for 24 hours), and LPSPRO (cultured in a medium containing LPS, and then immersed in 14,000 μg/L propolis for 24 hours) groups. The results showed that complement gene expression in larvae from the LPSIBU and LPSPRO groups were generally lower than in larvae from the LPS group. The number of macrophage migrations to the yolk in the LPSPRO group was also lower than in the LPS group. Histological structure of liver in all groups were considered normal. This study shows that Indonesian propolis has the potential to be used as an alternative to the substitution of NSAIDs.

Embora a própolis tenha sido relatada por ter atividade anti-inflamatória, seus efeitos no sistema complemento, uma parte do sistema imunológico inato, não foram muito estudados. Esta pesquisa foi conduzida para descobrir os efeitos da própolis da Indonésia nos níveis de expressão de C3, C1r/s, Bf, MBL e C6 em larvas de peixe-zebra induzidas por lipopolissacarídeo (LPS). Foram realizadas contagens de macrófagos que migram para o saco vitelino e histologia do fígado. As larvas foram divididas em quatro grupos: CON (cultivadas apenas em meio E3), LPS (cultivadas em meio contendo 0,5 μg/L de LPS), LPSIBU (cultivadas em meio contendo LPS e, em seguida, tratadas com 100 μg/L de ibuprofeno por 24 horas) e LPSPRO (cultivado em meio contendo LPS, e então imerso em própolis 14,000 μg/L por 24 horas). Os resultados mostraram que a expressão do gene do complemento em larvas dos grupos LPSIBU e LPSPRO foi geralmente menor que em larvas do grupo LPS. O número de migrações de macrófagos para a gema no grupo LPSPRO também foi menor que no grupo LPS. A estrutura histológica do fígado em todos os grupos foi considerada normal. Este estudo mostra que a própolis indonésia tem potencial para ser utilizada como alternativa na substituição dos AINEs (anti-inflamatórios não esteroides).

Assessment of the in vitro developmental toxicity of diethylstilbestrol and estradiol in the zebrafish embryotoxicity test.

The present study investigated the developmental toxicity of diethylstilbestrol (DES) in the zebrafish embryotoxicity test (ZET). This was done to investigate whether the ZET would better capture the developmental toxicity of DES than the embryonic stem cells test (EST) that was previously shown to underpredict the DES-induced developmental toxicity as compared to in vivo data, potentially because the EST does not capture late events in the developmental process. The ZET results showed DES-induced growth retardation, cumulative mortality and dysmorphisms (i.e. induction of pericardial edema) in zebrafish embryos while the endogenous ERα agonist 17ß-estradiol (E2) showed only growth retardation and cumulative mortality with lower potency compared to DES. Furthermore, the DES-induced pericardial edema formation in zebrafish embryos could be counteracted by co-exposure with ERα antagonist fulvestrant, indicating that the ZET captures the role of ERα in the mode of action underlying the developmental toxicity of DES. Altogether, it is concluded that the ZET differentiates DES from E2 with respect to their developmental toxicity effects, while confirming the role of ERα in mediating the developmental toxicity of DES. Furthermore, comparison to in vivo data revealed that, like the EST, in a quantitative way also the ZET did not capture the relatively high in vivo potency of DES as a developmental toxicant.

Toxicological assessment and developmental abnormalities induced by butylparaben and ethylparaben exposure in zebrafish early-life stages.

Toxicological effects of butylparaben (BuP) and ethylparaben (EtP) on zebrafish (Danio rerio) early-life stages are not well established. The present study evaluated, using zebrafish embryos and larvae, the toxicity of BuP and EtP through benchmark dose (BMD) approach. BuP was more toxic than EtP to zebrafish larvae. In fact, Lethal Concentration 50 (LC50) values at 96 h post-fertilization (hpf) for BuP and EtP were 2.34 mg/L and 20.86 mg/L, respectively. Indeed, BMD confidence interval (lower bound (BMDL) - upper bound (BMDU) was 0.91-1.92 mg/L for BuP and 10.8-17.4 mg/L for EtP. Zebrafish embryos exposed to 1 mg/L, 2.5 mg/L of BuP and 5 mg/L, 10 mg/L, 20 mg/L, 30 mg/L of EtP showed several developmental abnormalities and teratological effects compared to negative control. Exposed zebrafish developed reduced heartbeat, reduction in blood circulation, blood stasis, pericardial edema, deformed notochord and misshaped yolk sac. Embryos exposed to the highest concentrations of the chemicals (2.5 mg/L of BuP, 10 mg/L, 20 mg/L and 30 mg/L of EtP) showed the developmental abnormalities at 48 hpf while those treated with 1 mg/L of BuP and 10 mg/L of EtP reported behavioral changes at 72 hpf, including trembling of head, pectoral fins and spinal cord. This research identified the lethal and sublethal effects of BuP and EtP in zebrafish early-life stages and could be helpful to elucidate the developmental pathways of toxicity of parabens.

Toxicity Assessment of 4 Azo Dyes in Zebrafish Embryos.

Azo dyes are used widely as color additives in food, drugs, and cosmetics; hence, there is an increasing concern about their safety and possible health hazards. In the present study, we chose 4 azo dyes tartrazine, Sunset Yellow, amaranth, and Allura red and evaluated their developmental toxicity on zebrafish embryos. At concentration levels of 5 to 50 mM, we found that azo dyes can induce hatching difficulty and developmental abnormalities such as cardiac edema, decreased heart rate, yolk sac edema, and spinal defects including spinal curvature and tail distortion. Exposure to 100 mM of each azo dye was completely embryolethal. The median lethal concentration (LC50), median effective concentration (EC50), and teratogenic index (TI) were calculated for each azo dye at 72 hours postfertilization. For tartrazine, the LC50 was 47.10 mM and EC50 value was at 42.66 mM with TI ratio of 1.10. For Sunset Yellow, the LC50 was 38.93 mM and EC50 value was at 29.81 mM with TI ratio of 1.31. For amaranth, the LC50 was 39.86 mM and EC50 value was at 31.94 mM with TI ratio of 1.25. For Allura red, the LC50 was 47.42 mM and EC50 value was 40.05 mM with TI ratio of 1.18. This study reports the developmental toxicity of azo dyes in zebrafish embryos at concentrations higher than the expected human exposures from consuming food and drugs containing azo dyes.

Assessment of Histiotrophic Nutrition Using Fluorescent Probes.

Histiotrophic nutrition is a process whereby the rodent visceral yolk sac (VYS) internalizes exogenous macromolecules, degrades them, and sends the degradation products to the embryo. Quantification and visualization of histiotrophic nutrition can be accomplished using fluorescent tracer molecules such as fluorescein isothiocyanate-conjugated albumin (FITC-albumin). The methods are simple and can provide complimentary functional and structural information in studies of the effects of embryotoxicants on visceral yolk sac function.

Assessment on reticuloendotheliosis virus infection in specific-pathogen-free chickens based on detection of yolk antibody.

Reticuloendotheliosis virus (REV) is the most frequent exogenous virus that contaminates attenuated vaccines. Therefore, it is extremely important to select REV-free specific-pathogen-free (SPF) chicken embryos. Generally, REV infection is assessed by detecting REV antibodies in SPF chickens. This present study seeks to evaluate REV infection by replacing serum antibody detection with yolk antibody detection. A cohort of 40 nineteen-week-old SPF chickens were artificially inoculated with REV, with 32 SPF chickens raised in another isolation environment served as a blank control. Eggs and serum from 23-week-old chickens were sampled, and yolks were diluted separately to ratios of 1:150, 1:200, 1:300 and 1:400, which were detected together with serum. We found that the yolk antibody detection findings at a dilution of 1:300 had the highest coincidence rate compared with that based on serum antibody measurements. At a dilution ratio of 1:300 for yolk antibody, 72 chickens were continuously observed for 10 weeks from 25- to 34-weeks-old. Our findings were based on serum antibody or yolk antibody detection, and the evaluation results were completely consistent. Therefore, all serum antibody-positive chickens were yolk antibody-positive, and vice versa. Accordingly, vaccine producers can estimate REV cleanliness in a poultry farm by sampling yolk antibody titers.

An updated assessment of microglia depletion: current concepts and future directions.

Microglia are the principal resident immune cells in the central nervous system and are believed to be versatile players in both inflammatory and physiological contexts. On the one hand, in order to safeguard the microenvironment microglia can be rapidly activated by contact with microbial products or cell debris, thereby exerting the functions of innate immunity via phagocytosis and secretion of cytokines and chemokines. Conversely, microglia can also assist in brain development, synaptic plasticity and neural repair through the production of neurotrophic factors and clearance of myelin debris. It is now well accepted that the dysfunction of microglia and microglia-induced neuroinflammation are implicated in the occurrence and progression of many neurological diseases. Although the past decade has witnessed major progress in understanding of multi-tasking microglia, what remains largely enigmatic is the relative importance of microglia at different disease stages and how microglia should be targeted for optimal therapeutic efficacy. Notably, microglia depletion through genetic targeting or pharmacological therapies can be viewed as effective tools to stimulate new microglia to repopulate the central nervous system. Microglia depletion and subsequent repopulation at defined stages in various experimental animal model disorders allow us to extend our knowledge of molecular mechanisms, thus holding promise for designing strategies to resolve neuroinflammation and promote recovery. Herein we highlight the highly plastic and diverse phenotypes of microglia and outline the lessons learned from microglia depletion approaches.

Termination of pregnancy at very early gestation without visible yolk sac on ultrasound.

INTRODUCTION: Requests for termination of pregnancy (TOP) at very early gestation (≤6 weeks) can prove challenging for abortion services as the ultrasound feature usually accepted as definitive evidence of an intrauterine pregnancy (IUP), the presence of a yolk sac within a gestational sac, may not yet be evident. In 2011 the Edinburgh TOP service introduced a protocol permitting women to proceed to treatment without further investigations provided that ultrasound showed the features of an eccentrically placed gestational sac (≥3 mm) with a decidual reaction, and there were no signs, symptoms or risk factors for ectopic pregnancy. METHODS: A retrospective audit was conducted of outcomes of women presenting for TOP at ≤6 weeks' gestation over a 2-year period using the hospital computerised database. RESULTS: A total of 1155 women presented for TOP with an ultrasound gestational age of ≤6 weeks. Of these, 1030 (89%) had ultrasound evidence of a yolk sac. Eighty-seven women (7.5%) had an eccentrically placed gestational sac with a decidual reaction. All 87 women fulfilled our criteria to proceed to medical TOP, and 66 did so. In the remaining 21 cases, further investigations were performed before they proceeded to medical TOP. Two (0.17%) medical TOPs failed, both in women whose initial ultrasound had shown a yolk sac. CONCLUSION: Women with ultrasound features consistent with a very early IUP (≥3 mm eccentrically placed gestational sac with a decidual reaction) and without signs, symptoms or risk factors for ectopic pregnancy can proceed directly to medical TOP without the need for delay for further ultrasonography.

RETIRED: Determination of gestational age by ultrasound.

This document has been archived because it contains outdated information. It should not be consulted for clinical use, but for historical research only. Please visit the journal website for the most recent guidelines.

Ce document a été archivé, car il contient des informations périmées. Il ne devrait pas être consulté pour un usage clinique, mais uniquement pour des recherches historiques. Veuillez consulter le site web du journal pour les directives les plus récentes.

Assessment of histiotrophic nutrition using fluorescent probes.

Histiotrophic nutrition is a process whereby the rodent visceral yolk sac (VYS) internalizes exogenous macromolecules, degrades them, and sends the degradation products to the embryo for use in de novo macromolecular biosynthesis. This process is important for embryonic development during early gestation prior to the formation of the functional placenta. Quantification and visualization of histiotrophic nutrition can be accomplished using fluorescent tracer molecules such as fluorescein isothiocyanate-conjugated albumin (FITC-albumin) that can be visualized using fluorescent microscopy and quantified using fluorescent spectroscopy. The methods are simple and can provide complementary functional and structural information in studies of the effects of embryotoxicants on yolk sac function.

Ultrasound assessment of premenopausal bleeding.

Vaginal bleeding is the most common cause of emergency care in the first trimester of pregnancy and accounts for the majority of premenopausal bleeding cases. Ultrasound evaluation combined with a quantitative beta human chorionic gonadotropin test is an established diagnostic tool to assess these patients. Spontaneous abortion because of genetic abnormalities is the most common cause of vaginal bleeding; ectopic pregnancy and gestational trophoblastic disease are other important causes and in all patients presenting with first trimester bleeding, ectopic pregnancy should be suspected and excluded, as it is associated with significant maternal morbidity and mortality. A thorough knowledge of the normal sonographic appearance of intrauterine gestation is essential to understand the manifestations of an abnormal gestation. Arteriovenous malformation of the uterus is a rare but important cause of vaginal bleeding in the first trimester, as it has to be differentiated from the more common retained products of conception, with which it is often mistaken.

Assessment of yolk sac volume by 3D-sonography using the XI VOCAL method from 7 to 10 + 6 weeks of pregnancy.

PURPOSE: To access the yolk sac (YS) volume between 7 and 10 + 6 gestational weeks of pregnancy by threedimensional (3D) ultrasonography using extended imaging virtual organ computer-aided analysis (XI VOCAL) method. METHODS: For this cross-sectional study, 64 pregnant patients between 7 and 10 + 6 gestational weeks were enrolled and normal pregnancies were included. The XI VOCAL 10 slices manual method was used for the YS volumetry by 3D ultrasonography. The statistical analysis first obtained the means, medians, standard deviation, and maximum and minimum volume values. The correlation of YS volume to the gestational age (GA) and the crown-rump length (CRL) was evaluated by models of polynomial regression, being adjusted by determination coefficient (R (2)). RESULTS: The mean YS estimated volume ranged from 0.06 ± 0.03 cm(3) [0.02-0.11 cm(3)] to 0.16 ± 0.12 cm(3) [0.01-0.38 cm(3)] and showed to be weakly correlated to the GA [YS volume = exp(0.261 × GA + 0.008); R (2) = 0.14] and the CRL [YS volume = exp(0.033 × CRL + 0.035); R (2) = 0.13]. CONCLUSIONS: The YS volume estimated by 3D ultrasonography using the method XI VOCAL correlated weakly with GA and CRL in normal singleton pregnancies between 7 and 10 + 6 gestational weeks.

The assessment of the gestational sac diameter, crown-rump length, progesterone and fetal heart rate measurements at the 10th gestational week to predict the spontaneous abortion risk.

AIM: The assessment of the first trimester ultrasonographic and progesterone measurements to predict spontaneous abortion risk. METHODS: Ninety-nine women at the 10th week of pregnancy were included in this prospective study. Their ages, progesterone (P) levels, mean gestational sac diameters (MGSD), crown-rump lengths (CRL), MGSD-CRL measurements and fetal heart rates (FHR) were recorded. These variables were compared by abortion status. RESULTS: Patients were followed up until the 20th weeks, and 8 (8.08%) aborted. We evaluated the variables by receiver operator characteristic curve to predict abortion. Only the areas under the curve for P levels (0.29) and for MGSD--CRL (0.16) were statistically significant We. also made logistic regression analysis to predict abortion. P level and FHR were statistically significant (P < 0.01) when the threshold value was 50%. Negative predictive value of the model was 98.9%, and positive predictive value was 50%. Overall, this model can correctly classify 94.9% of the groups. We determined threshold values for MGSD-CRL (> or =10 mm) and P (> or =25 ng/mL) to predict abortion, but not for FHR. Interestingly, 14 patients with FHR > or =175 beats/min did not abort. For the MGSD-CRL threshold, we can predict that the pregnancy will continue with 95.78% probability, with 67% sensitivity and 89% specificity. For the P threshold, the pregnancy will continue with 97.85% probability, with 80% sensitivity and 80% specificity. CONCLUSION: MGSD-CRL and P could predict patients with low abortion risk. However, at the 10th week of pregnancy, FHR > or =175 beats/min should be evaluated for this purpose by future studies with larger sample sizes.

Assessment of digestive enzymes activity during the fry development of the endangered Caspian brown trout Salmo caspius.

The study of digestive enzymes activity at Salmo caspius fry showed that enzymes were available at the moment of mouth opening on the first day post hatching (dph) and the activity of enzymes showed no significant difference from the hatching day 28 dph. An increased activity was seen between 32 and 43 dph and this activity was significantly higher than the activity during the first 28 days. In the primary stages after yolk sac resorption (43-58 dph), enzymes activity showed an increased profile, however none of them showed a significant difference between 43 and 58 dph.

Functional linear discriminant analysis: a new longitudinal approach to the assessment of embryonic growth.

BACKGROUND: Functional linear discriminant analysis (FLDA) is a new growth assessment technique using serial measurements to discriminate between normal and abnormal fetal growth. We used FLDA to assess and compare growth in live pregnancies destined to miscarry with those remaining viable. METHODS: This was a prospective cohort study of women with ultrasound scans on at least two separate occasions showing live pregnancies. Serial crown-rump length (CRL), mean gestational sac diameter and mean yolk sac diameter measurements were recorded. The ability of FLDA to predict subsequent miscarriage was compared with that of a single CRL measurement. RESULTS: Of 521 included pregnancies, 493 (94.6%) remained viable at 14 weeks and 28 (5.4%) miscarried. The CRL growth rate was significantly lower in those that miscarried (one-sample t-test, P = 2.638E-22). The sensitivity of FLDA in predicting miscarriage from serial CRL measurements was 60.7% and specificity was 93.1% [positive predictive value (PPV) 33.3%, negative predictive value (NPV) 97.7%]. This was significantly better for predicting miscarriage than a single CRL observation of more than 2SD below that expected (sensitivity 53.6%, specificity 72.2%, PPV 9.9%, NPV 96.5%). CONCLUSIONS: FLDA discriminates between normal and abnormal growth to predict miscarriage with high specificity. FLDA predicts miscarriage better than a single observation of a small CRL.

Assessment of biological effects of chlorinated hydrocarbons in osprey chicks.

Osprey (Pandion haliaetus) eggs were collected during 1995 and 1996 at seven sites along the Fraser and Columbia River systems of British Columbia, Canada, and Washington and Oregon, USA. Fifty-four eggs were placed into a laboratory incubator. Thirty-eight of the hatched chicks were sacrificed within 24 h. Hatching success did not differ among sites and therefore between treatment and reference areas. Residual yolk sacs of eggs collected downstream of the large bleached-kraft pulp mill at Castlegar contained greater mean concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, 2,930 ng/kg lipid) compared with reference sites such as the Nechako River, an upper tributary of the Fraser system (33.7 ng/kg). Total polychlorinated biphenyls (PCBs) in yolk sacs were also higher at Castlegar and in samples from the Columbia River downstream of Portland, Oregon, compared with those from the Nechako River. Concentrations of measured chemicals, including TCDD toxic equivalents (TEQs), total PCBs, p,p'-dichlorodiphenylethylene (p,p'-DDE), and other organochlorines were not different in eggs that failed to hatch compared with calculated whole-egg values for hatched eggs. There were significant biochemical responses; a hepatic cytochrome P4501A (CYP1A) cross-reactive protein was detected in all samples tested and correlated positively with ethoxyresorufin o-deethylase (EROD) activity and yolk sac concentrations of TEQs and total PCBs. Tissue concentrations of vitamin A compounds varied among sites and correlated positively with yolk sac concentrations of TEQs and PCBs. Morphological, histological, and other physiological parameters, including chick growth, edema, deformities, and hepatic and renal porphyrin concentrations, neither varied among sites nor showed concentration-related effects.

Parallel Doppler assessment of yolk sac and intervillous circulation in normal pregnancy and missed abortion.

This study assessed yolk sac morphology and vascularity and intervillous blood flow in normal early pregnancy and missed abortion. Transvaginal colour and pulsed Doppler were used in a prospective analysis of 87 normal pregnancies and 48 missed abortions between 6 and 12 weeks gestation. The Kruskal-Wallis rank test was used to calculate the difference in yolk sac diameter and vascularity visualization rate between gestational weeks. Repeated measures analysis of variance was used for comparison of the intervillous circulation between groups. The growth of the yolk sac was considered statistically significant between gestational weeks 6 and 9, being most prominent between 9 and 10 weeks of gestation. Vascularity of the yolk sac, characterized by low velocity and absence of diastolic flow, was demonstrated in 67 per cent of normal pregnancies. Yolk sac blood flow was detected in 19 per cent of the patients with missed abortion. Doppler analysis of the intervillous circulation demonstrated decreased peak velocity of the continuous flow in patients with missed abortion for gestational weeks 11 and 12. It is concluded that progressive decrease of yolk sac vascularity coincides with visualization of more prominent colour-coded areas within the intervillous space. In patients with missed abortion, such changes do not occur.

Dietary myo-inositol therapy in hyperglycemia-induced embryopathy.

Dysmorphogenesis in diabetic mothers occurs more frequently than in the general population. This phenomenon is believed to be caused by the teratogenic effects of metabolic fuel mixtures with associated membrane injury and aberrations in the biochemical constituents. The present experiment was designed to determine: 1) if hyperglycemia-induced membrane injury is associated with intracellular and/or extracellular lipid disturbances; 2) if supplemental myo-inositol therapy prevents hyperglycemia-induced embryopathy; 3) if a correlation exists between dietary myo-inositol, serum and tissue levels of myo-inositol, and conceptus development; and 4) the cellular content of arachidonic acid following myo-inositol supplementation. Sixty-five female Sprague-Dawley rats were mated, and divided into three groups. One group was nondiabetic normal controls, and two groups had diabetes experimentally induced with streptozotocin. Of the diabetic groups, one received a normal diet, while the other received a myo-inositol-supplemented diet during the period of organogenesis. Blood samples were collected on days 0 and 12 of pregnancy. Embryos and yolk sacs were analyzed for myo-inositol and arachidonic acid levels, using mass spectrochromatography. Dietary myo-inositol supplementation of diabetic mothers resulted in a significant decrease in the incidence of neural tube defects when compared with diabetics not receiving supplements (9.5 vs. 20.4%; P < 0.05). This protective effect was incomplete, based on the incidence observed in the nondiabetic controls (9.5 vs. 3.8%; P < 0.05). The myo-inositol embryonic tissue levels in the diabetic group which had been fed a regular diet without supplementation were significantly lower than in the nondiabetic group. Dietary therapy successfully restored myo-inositol levels in the yolk sacs, as suggested by similar tissue levels in diabetics receiving myo-inositol supplementation and normal controls (18.7 +/- 1.3 vs. 19.1 +/- 2.0 ng/mg; P = ns). Dietary therapy, however, failed to restore myo-inositol levels in the embryos, suggesting hyperglycemia-induced faulty transport of nutrients from the yolk sac to the embryo. No correlation was noted between maternal blood levels of myo-inositol, with or without supplementation, and the clinical outcome. Tissue arachidonic acid levels were markedly reduced in the conceptuses of diabetic mothers with (0.4 +/- 0.1 micrograms/mg) or without (0.25 +/- 0.08 micrograms/mg) myo-inositol supplementation when compared to the nondiabetic controls (3.33 +/- 0.24 micrograms/mg). These data demonstrate that diabetes-induced embryopathy is associated with a deficiency state in both myo-inositol and arachidonic acid. The myo-inositol deficiency is not demonstrated at the serum level, but rather at the tissue level, suggesting a paracrine action. Dietary supplementation of myo-inositol is associated with an increase in tissue myo-inositol levels and a decrease in malformations. This therapy holds promise for use as a dietary prophylaxis against diabetic embryopathy.