Glyphosate exposure in pregnancy and shortened gestational length: a prospective Indiana birth cohort study.

BACKGROUND: Glyphosate (GLY) is the most heavily used herbicide worldwide but the extent of exposure in human pregnancy remains unknown. Its residues are found in the environment, major crops, and food items that humans, including pregnant women, consume daily. Since GLY exposure in pregnancy may also increase fetal exposure risk, we designed a birth-cohort study to determine exposure frequency, potential exposure pathways, and associations with fetal growth indicators and pregnancy length. METHOD: Urine and residential drinking water samples were obtained from 71 women with singleton pregnancies living in Central Indiana while they received routine prenatal care. GLY measurements were performed using liquid chromatography-tandem mass spectrometry. Demographic and survey information relating to food and water consumption, stress, and residence were obtained by questionnaire. Maternal risk factors and neonatal outcomes were abstracted from medical records. Correlation analyses were used to assess relationships of urine GLY levels with fetal growth indicators and gestational length. RESULTS: The mean age of participants was 29 years, and the majority were Caucasian. Ninety three percent of the pregnant women had GLY levels above the limit of detection (0.1 ng/mL). Mean urinary GLY was 3.40 ng/mL (range 0.5-7.20 ng/mL). Higher GLY levels were found in women who lived in rural areas (p = 0.02), and in those who consumed > 24 oz. of caffeinated beverages per day (p = 0.004). None of the drinking water samples had detectable GLY levels. We observed no correlations with fetal growth indicators such as birth weight percentile and head circumference. However, higher GLY urine levels were significantly correlated with shortened gestational lengths (r = - 0.28, p = 0.02). CONCLUSIONS: This is the first study of GLY exposure in US pregnant women using urine specimens as a direct measure of exposure. We found that > 90% of pregnant women had detectable GLY levels and that these levels correlated significantly with shortened pregnancy lengths. Although our study cohort was small and regional and had limited racial/ethnic diversity, it provides direct evidence of maternal GLY exposure and a significant correlation with shortened pregnancy. Further investigations in a more geographically and racially diverse cohort would be necessary before these findings could be generalized.

Recessed elliptical-centric view-ordering for contrast-enhanced 3D MR angiography of the carotid arteries.

Fast arterial-venous transit in the carotid arteries requires accurate, reliable timing of the acquisition to the bolus transit to maximize arterial signal and minimize venous artifacts. The rising edge of the bolus is not utilized in conventional elliptical-centric view-ordering because the critical k-space center must be acquired with full arterial enhancement. In this study, a recessed elliptical-centric view-ordering scheme is introduced in which the k-space center is acquired a few seconds following scan initiation. The recessed view-ordering is shown to be more robust to timing errors than the conventional scheme in a study of 37 patients.

Cross-sectional pattern of collateral vessels in patients with superficial femoral artery occlusion.

RATIONALE AND OBJECTIVES: The purpose of this study was to identify the cross-sectional location of collateral vessels in patients with peripheral vascular disease on three-dimensional magnetic resonance angiograms (3D MRAs) to suggest sites for intravascular or transcutaneous angiogenesis gene delivery in the lower extremity. METHODS: The axial locations were measured and categorized by tissue compartments, as well as by radial coordinates with respect to the femur. RESULTS: Collateral vessels in the thigh were identified in 24 of 93 consecutive patients who underwent peripheral 3D MRA. Ninety-one percent (99/109) of the observed collaterals were located near the adductor canal level of the thigh, with 78% (31/46) of these collaterals located in the fat in or surrounding the posterior muscle. CONCLUSIONS: The majority of collateral vessels in the thigh are located in the fat or muscle within the posterior compartment near the femur at the level of the adductor canal.

Thrombolysis for native arterial occlusions of the lower extremities: clinical outcome and cost.

INTRODUCTION: Intra-arterial thrombolysis is commonly used as the initial treatment of acute or subacute lower extremity ischemia. METHODS: To evaluate the efficacy and cost of thrombolysis, we retrospectively analyzed 100 consecutive cases (87 patients) in which intra-arterial lysis (urokinase) was used as the initial treatment for native arterial lower extremity occlusive disease. The mean age of patients was 67 years, 57% of the patients were male, and preexisting peripheral vascular disease was present in 74%. Presenting symptoms were limb-threatening ischemia (53%) and claudication (47%). Acute symptoms (< 2 weeks' duration) were present in 48%. RESULTS: The 30-day morbidity rate was 31%, and four patients died. Complications were significant bleeding (23%), ischemic stroke (1%), and renal failure with (2%) and without (2%) dialysis. Concomitant angioplasty was performed in 63%. Complete or significant lysis as demonstrated with angiography was achieved in 75% of iliac, 58% of femoropopliteal, and 41% of crural vessels (P <.001). Within 30 days of lysis, 9% of patients underwent major amputation and 20% surgical revascularization (in 3 patients the extent of revascularization was lessened by the lytic therapy). Amputation-free survival was 83% and 75% at 6 months and 2 years, respectively. Relief of ischemia (defined as relief of claudication or limb salvage without major surgical intervention) was achieved in only 70% and 43% of patients at 30 days and 2 years, respectively (Kaplan-Meier analysis; mean follow-up, 31 months). Patients with aortoiliac disease had significantly better outcomes than those with infrainguinal disease (P =.03). Duration or type of presenting symptoms did not predict outcome. The cost of the initial hospitalization per patient for thrombolysis was $18,490. CONCLUSION: Thrombolysis can be as or more costly than surgery and is associated with a suboptimal outcome in a significant number of patients. These data lead us to caution against a uniform policy of initial thrombolysis for patients who present with lower extremity ischemia.

Contrast-enhanced peripheral MR angiography from the abdominal aorta to the pedal arteries: combined dynamic two-dimensional and bolus-chase three-dimensional acquisitions.

UNLABELLED: Wang Y, Winchester PA, Khilnani NM, et al. Contrast-enhanced peripheral MR angiography from the abdominal aorta to the pedal arteries: Combined dynamic two-dimensional and bolus-chase three-dimensional acquisitions. Invest Radiol 2001;36:170-177. RATIONALE AND OBJECTIVES: To obtain reliable contrast-enhanced peripheral MR angiography for imaging peripheral vascular disease from the abdominal aorta to the pedal arteries. METHODS: A protocol consisting of contrast-enhanced, dynamic two-dimensional (2D) acquisition at the feet and calf and bolus-chase three-dimensional (3D) acquisition from the abdominal aorta to the calf was developed and applied in patients with peripheral vascular disease. The performance of this integrated protocol was assessed in 89 consecutive patients. RESULTS: The bolus-chase 3D acquisition was of diagnostic quality in 100% of the acquisitions in the abdomen, 96% in the thigh, and 43% in the calf. The poor quality of the calf acquisitions was due to insufficient spatial resolution, poor arterial signal, and venous contamination. Diagnostic-quality images were obtained in 100% of the dynamic 2D acquisitions of the calf and 98% of the feet. CONCLUSIONS: The combined dynamic 2D and bolus-chase 3D contrast-enhanced MR angiography technique provides diagnostic images of the entire lower extremity.

Anatomically tailored k-Space sampling for bolus-chase three-dimensional MR digital subtraction angiography.

The purpose of this study was to evaluate a variable k-space sampling method for bolus-chase three-dimensional magnetic resonance digital subtraction angiography in the arterial system from the abdomen to the calf. Imaging time was minimized by tailoring the acquisition according to the vascular anatomy of the station. For images obtained in 30 patients, results with the modified protocol were compared to those with the previously published protocol. For all stations, significant improvement (P <.001) was found with the modified protocol.

Cardiovascular responses to static exercise in patients with Brown-Séquard syndrome.

1. The purpose of this study was to determine the contributions of central command and the exercise pressor reflex in regulating the cardiovascular response to static exercise in patients with Brown-Sequard syndrome. In this rare condition, a hemisection of the spinal cord typically leaves one side of the body with diminished sensation and normal motor function and the other side with diminished motor function and normal sensation. 2. Four, otherwise healthy, patients with Brown-Sequard syndrome and varying degrees of motor and sensory dysfunction were studied during four isometric knee extension protocols involving both voluntary contraction and electrically stimulated contractions of each leg. Heart rate, blood pressure, force production and ratings of perceived exertion were measured during all conditions. Measurements were also made during post-contraction thigh cuff occlusion and during a cold pressor test. 3. With the exception of electrical stimulation of the leg with a sensory deficit, protocols yielded increases in heart rate and blood pressure. Cuff occlusion sustained blood pressure above resting levels only when the leg had intact sensation. 4. While voluntary contraction (or attempted contraction) of the leg with a motor deficit produced the lowest force, it produced the highest ratings of perceived exertion coupled with the greatest elevations in heart rate and blood pressure. 5. These data show that the magnitude of the heart rate and blood pressure responses in these patients was greatly affected by an increased central command; however, there were marked cardiovascular responses due to activation of the exercise pressor reflex in the absence of central command.

Breath-hold three-dimensional contrast-enhanced coronary MR angiography: motion-matched k-space sampling for reducing cardiac motion effects.

A view order that matches k-space sampling to cardiac motion within the acquisition window was developed for breath-hold three-dimensional contrast material-enhanced coronary magnetic resonance angiography. In vivo experiments in seven volunteers demonstrated that blurring was substantially reduced with this motion-matched view order as compared with the standard centric view order. Coronary arteries were well delineated.

Cyclone mitigation, resource allocation and post-disaster reconstruction in south India: lessons from two decades of research.

This paper opens with a history of development and disaster-prevention strategies in a cyclone-prone area of the east coast of India and traces the evolution in the area of British and Indian governments' programmes and policy over a century. Research over the last 20 years has shown, however, that the programmes and policies have failed to balance economic growth with safety. Resources intended for the benefit of all have been diverted by alliances of powerful people to a small minority, and recent developments have reduced the physical protection of the area. The result is that increasing numbers of people are vulnerable to the effects of cyclones and floods. The findings suggest that the best way to reduce vulnerability is to improve the socio-economic standing of the most vulnerable and for this to happen these people must have an assured income based on assets that will enable them to acquire social and economic credit-worthiness within the local economy. This paper presents evidence that suggests that non-governmental organisation (NGO)-supported co-operatives are the best way to achieve this through self-help and self-employment schemes. It also suggests that NGOs should be encouraged to take up environmentally and ecologically beneficial activities involving the poorest groups in the communities, in this way combining sustained self-employment with environmental protection.

Comparison of two-dimensional MR digital subtraction angiography of the lower extremity with x-ray angiography.

PURPOSE: To perform a preliminary evaluation of the diagnostic accuracy of contrast-enhanced, two-dimensional (2D) magnetic resonance (MR) digital subtraction angiography (DSA) of the lower extremity by comparison with x-ray angiography (XRA). MATERIALS AND METHODS: Forty lower extremities in 22 patients were imaged at multiple levels with both XRA and 2D MR DSA. Images were retrospectively analyzed by three radiologists in a randomized blinded manner. Seventeen vascular segments were graded as an insignificant lesion, a significant lesion, or as an occlusion. With the use of segments well depicted with XRA as the gold standard, the sensitivity, specificity, and accuracy of 2D MR DSA, as compared with XRA, were evaluated. The McNemar-Stuart-Maxwell test was performed to determine the significance of any differences found. RESULTS: Three hundred eighty-three arterial segments were evaluated with both techniques. Three hundred one segments were well depicted with XRA. There was no significant difference between 2D MR DSA and XRA for assessing the degree of occlusive disease in these 301 segments (.25 < P < .5). The sensitivity, specificity, and diagnostic accuracy of 2D MR DSA were found to be 90%, 98%, and 93%, respectively. CONCLUSION: Two-dimensional MR DSA is an accurate method for assessing arterial lesions in the lower extremity.

In vitro evaluation of the relative thrombolytic efficiency of forced intrathrombic injections: saline versus urokinase.

PURPOSE: To compare the rates of thrombolysis produced by forced intrathrombic injections of saline versus urokinase, as well as automated versus manual injections of urokinase, with use of an in vitro model of a vascular occlusion. MATERIALS AND METHODS: The rates of thrombolysis produced by forced intrathrombic injections of saline and urokinase were compared in an in vitro radiometric model utilizing I-125-labeled thrombus. Similar experiments were performed to compare manual and automated injections of urokinase. The dissolution of the thrombus was quantitatively monitored with use of a scintillation detector. Averaged time activity data for each type of experiment were fit to exponential functions and half times of lysis calculated. The differences in the half times for the experiments being compared were evaluated for significance with use of the Student t test. RESULTS: The half times of lysis produced by forced intrathrombic injections of urokinase were substantially and significantly shorter than those produced by forced saline injections. The half time of lysis produced by automated injections was not significantly different than that produced by manual injections. CONCLUSIONS: Forced intrathrombic injections of urokinase produce faster and substantially more thrombolysis when compared with similarly administered saline. Also, for forced intrathrombic injections of lytic agents, an automated injector is an equivalent alternative to manual injections.

Timing algorithm for bolus chase MR digital subtraction angiography.

To acquire multiple longitudinal locations in the lower extremity after a single contrast injection, appropriate table translation and contrast injection are required. An approximate model based on constant bolus velocity was developed to describe the space-time course of a contrast bolus in the lower extremity. This model was verified in dynamic MR angiograms acquired in a group of patients using time-resolved 2D MR digital subtraction angiography (MRDSA). From this contrast bolus passage model, a timing algorithm for table translation and contrast injection was developed for bolus chase MRDSA, subsequently validated in bolus chase 2D MRDSA experiments. All targeted major peripheral arteries were well depicted in bolus chase 2D MRDSA using this timing algorithm and a single 15-ml contrast dose.

Bolus-chase MR digital subtraction angiography in the lower extremity.

A bolus-chase magnetic resonance (MR) angiographic technique performed with a prototypic stepping table and coil holder and a 15-20-mL injection of contrast material was developed to depict the entire lower extremity. Image acquisition was synchronized with passage of the contrast medium bolus through the lower extremity. Ten subjects underwent the examination, which was performed in less than 1 minute. All major arteries were well demonstrated in all cases.

Activation of the insular cortex during dynamic exercise in humans.

1. The insular cortex has been implicated as a region of cortical cardiovascular control, yet its role during exercise remains undefined. The purpose of the present investigation was to determine whether the insular cortex was activated during volitional dynamic exercise and to evaluate further its role as a site for regulation of autonomic activity. 2. Eight subjects were studied during voluntary active cycling and passively induced cycling. Additionally, four of the subjects underwent passive movement combined with electrical stimulation of the legs. 3. Increases in regional cerebral blood flow (rCBF) distribution were determined for each individual using single-photon emission-computed tomography (SPECT) co-registered with magnetic resonance (MR) images to define exact anatomical sites of cerebral activation during each condition. 4. The rCBF significantly increased in the left insula during active, but not passive cycling. There were no significant changes in rCBF for the right insula. Also, the magnitude of rCBF increase for leg primary motor areas was significantly greater for both active cycling and passive cycling combined with electrical stimulation compared with passive cycling alone. 5. These findings provide the first evidence of insular activation during dynamic exercise in humans, suggesting that the left insular cortex may serve as a site for cortical regulation of cardiac autonomic (parasympathetic) activity. Additionally, findings during passive cycling with electrical stimulation support the role of leg muscle afferent input towards the full activation of leg motor areas.

Magnetic resonance imaging of myocardial infarction during prothrombin complex concentrate therapy of hemophilia A.

In patients with hemophilia, prothrombin complex concentrates (PCCs) have been successfully used to bypass inhibitors to factor VIII during bleeding episodes. The use of PCCS, including FEIBA (factor eight inhibitor bypassing activity), has been associated with thromboembolic complications. Myocardial infarction (MI) is a rare but serious complication, reported in 13 previous cases, six in the pediatric age group. In all four patients who died during the acute MI, autopsy revealed extensive myocardial hemorrhage. The hearts of three other patients examined at least 5 months after the acute MI showed no evidence of prior hemorrhage. Magnetic resonance (MR) imaging has been shown to be able to evaluate the sequelae of myocardial infarction in adults with coronary artery disease and in children with Kawasaki syndrome. We report the first case of the use of MR imaging in the evaluation of myocardial damage during the acute stage of a FEIBA-associated MI in a 10-year-old boy.

Facial cooling-induced bradycardia: attenuating effect of central command at exercise onset.

Facial cooling (FC) elicits a marked bradycardia at rest that appears to be reduced during exercise. This study was done to delineate the effects of exercise mediated central command from those of muscle afferent feedback and sympathetic stimulation on the attenuation of the bradycardic effect of FC during the onset of exercise. Ten healthy subjects (26 +/- 2 yr) were exposed to FC under five different conditions: 1) seated rest on the cycle ergometer, 2) onset of mild exercise (resting HR + 20 beats.min-1), 3) onset of moderate exercise (resting HR + 50 beats.min-1), 4) seated rest on the ergometer during electrical stimulation, and 5) seated rest on the ergometer during a cold immersion test (CT) (one hand immersed in an ice slurry at 0 degree C). The two exercise intensities were presumed to provide different degrees of central command. Electrical stimulation of the quadriceps was assumed to provide isolated muscle afferent feedback, while the CT served as a sympathetic stimulus. Beat-by-beat data were recorded for HR and mean arterial blood pressure for the duration of each test (50 s), and a rating of perceived pain was taken after each FC. FC elicited significant increases in mean arterial pressure during mild and moderate exercise compared with resting control (P < 0.05) and during moderate exercise compared to exercise without FC (P < 0.05). Mean decreases in HR during FC were similar for resting control (-12 +/- 3 beats.min-1), electrical stimulation (-10 +/- 3 beats.min-1), and CT (-9 +/- 3 beats.min-1). The HR response to FC during mild exercise (-7 +/- 2 beats.min-1) was significantly different (P < 0.05) from the rest condition; however, there was no significant bradycardia (-2 +/- 2 beats.min-1; P > 0.05) during onset of moderate exercise. These findings suggest that the magnitude of cold face-induced bradycardia may be attenuated at exercise onset by neural signals related to the higher levels of central motor command associated with heavier exercise.

Congenital fusion of the fourth and fifth metacarpals associated with primary gonadal failure.

Congenital fusion of the fourth and fifth metacarpals is described in a male infant and his maternal grandfather. Primary gonadal failure, which is present in the infant, has not been noted in previously, reported cases. The pedigree in this family is compatible with X-linked recessive or autosomal dominant inheritance with incomplete penetrance.