Precision measurement of the neutron twist-3 matrix element d(2)(n): probing color forces

Double-spin asymmetries and absolute cross sections were measured at large Bjorken x  (0.25≤x≤0.90), in both the deep-inelastic and resonance regions, by scattering longitudinally polarized electrons at beam energies of 4.7 and 5.9 GeV from a transversely and longitudinally polarized (3)He target. In this dedicated experiment, the spin structure function g(2)((3)He) was determined with precision at large x, and the neutron twist-3 matrix element d(2)(n) was measured at ⟨Q(2)⟩ of 3.21 and 4.32  GeV(2)/c(2), with an absolute precision of about 10(-5). Our results are found to be in agreement with lattice QCD calculations and resolve the disagreement found with previous data at ⟨Q(2)⟩=5  GeV(2)/c(2). Combining d(2)(n) and a newly extracted twist-4 matrix element f(2)(n), the average neutron color electric and magnetic forces were extracted and found to be of opposite sign and about 30  MeV/fm in magnitude.

Dentists' perspectives on caries-related treatment decisions

OBJECTIVE

To assess the impact of patient risk status on Colombian dentists' caries related treatment decisions for early to intermediate caries lesions (ICDAS code 2 to 4).

METHODS

A web-based questionnaire assessed dentists' views on the management of early/intermediate lesions. The questionnaire included questions on demographic characteristics, five clinical scenarios with randomised levels of caries risk, and two questions on different clinical and radiographic sets of images with different thresholds of caries.

RESULTS

Questionnaires were completed by 439 dentists. For the two scenarios describing occlusal lesions ICDAS code 2, dentists chose to provide a preventive option in 63% and 60% of the cases. For the approximal lesion ICDAS code 2, 81% of the dentists chose to restore. The main findings of the binary logistic regression analysis for the clinical scenarios suggest that for the ICDAS code 2 occlusal lesions, the odds of a high caries risk patient having restorations is higher than for a low caries risk patient. For the questions describing different clinical thresholds of caries, most dentists would restore at ICDAS code 2 (55%) and for the question showing different radiographic thresholds images, 65% of dentists would intervene operatively at the inner half of enamel. No significant differences with respect to risk were found for these questions with the logistic regression.

CONCLUSION

The results of this study indicate that Colombian dentists have not yet fully adopted non-invasive treatment for early caries lesions.

JLab measurement of the 4He charge form factor at large momentum transfers

The charge form factor of 4He has been extracted in the range 29  fm(-2) ≤ Q2 ≤ 77  fm(-2) from elastic electron scattering, detecting 4He recoil nuclei and electrons in coincidence with the high resolution spectrometers of the Hall A Facility of Jefferson Lab. The measurements have uncovered a second diffraction minimum for the form factor, which was predicted in the Q2 range of this experiment. The data are in qualitative agreement with theoretical calculations based on realistic interactions and accurate methods to solve the few-body problem.

Quantitative light-induced fluorescence to measure enamel remineralization in vitro

The aim of this study was to compare the ability of quantitative light-induced fluorescence (QLF) and surface microhardness (SMH) to measure the remineralization of enamel subsurface lesions, using a pH-cycling model including treatment with 0-ppm, 550-ppm or 1,100-ppm sodium fluoride (NaF) dentifrices.

METHODS

Subsurface lesions were created in human enamel specimens (n = 36) and exposed to a remineralization pH-cycling model for 14 days. The pH-cycling model was performed in an automated system where specimens were subjected to a demineralizing solution for 20 min and treatment for 1 min and were then remineralized for 7 h 39 min, 3 times daily. The treatments consisted of 3 NaF, silica-containing dentifrices (0 ppm F; 550 ppm F; 1,100 ppm F). The outcome variables were: change from baseline in surface hardness and percentage change from baseline in fluorescence. An ANCOVA explored differences between different treatment groups (at the p < 0.05 level). Associations between QLF and SMH were evaluated using Spearman's correlation coefficient.

RESULTS

The percentage SMH changes were 14.9 ± 2.1%, 56.6 ± 9.6% and 103.9 ± 14.6% for the 0-, 550- and 1,100-ppm F dentifrices, respectively. The percentage fluorescence changes were 15.6 ± 7.1%, 59.8 ± 11.9% and 85 ± 13.2%, respectively. The differences between all pairwise comparisons were statistically significant for both methods (p = 0.001). QLF correlated with SMH (r = 0.67).

CONCLUSIONS

Both the SMH and QLF methods demonstrated a significant F dose response for toothpaste in this in vitro remineralization model, and both methods were able to distinguish treatments with different F levels.

Beyond UV radiation: a skin under challenge

Since ancient times, human beings have been trying to protect their skin against the adverse effects of the sun. From the first mineral sunscreens used by Egyptians, to the current more sophisticated ultraviolet (UVA/UVB) organic sunscreens, progress has been made in terms of sun protection and deeper knowledge of skin physiology has been acquired in the process. The solar spectrum is composed of radiations of various wavelengths having specific, as well as overlapping effects on skin. UVB is mainly responsible for sunburn and DNA dimer formation that can lead to mutation. UVA generates oxidative reactions affecting DNA, proteins and lipids, and is also immunosuppressive. Recently, visible light and infrared radiation (IR) have been associated with oxidative damage and IR has been additionally linked to adverse heat effects on skin. Numerous other extrinsic factors, related to environment and lifestyle, also affect the appearance of skin, precipitating ageing. New molecular mechanisms linking sun and environmental factors to skin ageing have been identified: IR affects mitochondrial integrity and specific heat receptors also mediate some of its effects, tryptophan is a chromophore for UVB, and the aryl hydrocarbon receptor (AhR) is activated by light and xenobiotics to alter skin physiology. Integrating all these new elements is changing the way we think about skin extrinsic ageing. Is UVA/UVB sunscreen protection still enough for our skin?

Growth modulation index as metric of clinical benefit assessment among advanced soft tissue sarcoma patients receiving trabectedin as a salvage therapy

BACKGROUND

The growth modulation index (GMI) is the ratio of time to progression with the nth line (TTP(n)) of therapy to the TTP(n)(-1) with the n-1th line. GMI >1.33 is considered as a sign of activity in phase II trials.

PATIENTS AND METHODS

This retrospective analysis evaluated the concordance between the GMI and the efficacy outcomes in 279 patients with advanced soft tissue sarcoma (ASTS) treated with trabectedin 1.5 mg/m² (24-h infusion every 3 weeks) in four phase II trials.

RESULTS

One hundred and forty-two (51%) patients received one prior line and 137 ≥ 2 lines. The median TTP(n) was 2.8 months (range 0.2-26.8), whereas the median TTP(n)(-1) was 4.0 months (0.3-79.5). The median GMI was 0.6 (0.0-14.4). Overall, 177 patients (63%) had a GMI <1; 21 (8%) a GMI equal to 1-1.33 and 81 (29%) a GMI >1.33, which correlated with the median overall survival in those patients (9.1, 13.9 and 23.8 months, respectively, P = 0.0005). A high concordance rate between the GMI and response rate (P < 0.0001) and progression-free survival (PFS, P < 0.0001) was observed. Good performance status (PS) was the only factor associated with GMI >1.33 (PS = 0; P < 0.04).

CONCLUSIONS

A high GMI was associated with favorable efficacy outcomes in patients treated with trabectedin. Further research is needed to assess GMI as an indicator in this setting.

Antioxidant and anti-inflammatory effects of a hypoglycemic fraction from Cucurbita ficifolia Bouché in streptozotocin-induced diabetes mice

Type 2 diabetes is characterized by oxidative stress and a chronic low-grade inflammatory state, which also play roles in the pathogenesis of this disease and the accompanying vascular complications by increasing the production of free radicals and pro-inflammatory cytokines. Cucurbita ficifolia Bouché (C. ficifolia) is an edible Mexican plant whose hypoglycemic activity has been demonstrated in several experimental and clinical conditions. Recently, D-chiro-inositol has been proposed as the compound responsible for the hypoglycemic effects; however, the antioxidant and anti-inflammatory potential of this plant has not yet been explored. The aim of this research is to study the influence of a hypoglycemic, D-chiro-inositol-containing fraction from the C. ficifolia fruit (AP-Fraction) on biomarkers of oxidative stress, as well as on the inflammatory cytokines in streptozotocin-induced diabetes. The AP-Fraction obtained from the mature fruit of C. ficifolia contained 3.31 mg of D-chiro-inositol/g of AP-Fraction. The AP-Fraction was administrated daily by gavage to normal mice for 15 days as a preventive treatment. Then these animals were given streptozotocin, and the treatments were continued for an additional 33 days. Pioglitazone was used as a hypoglycemic drug for comparison. Administration of the AP-Fraction significantly increased glutathione (GSH) and decreased malondialdehyde (MDA) in the liver without significantly affecting the levels in other tissues. The AP-Fraction reduced TNF-α and increased IL-6 and IFN-γ in serum. Interestingly, the AP-Fraction also increased IL-10, an anti-inflammatory cytokine. These results suggest that C. ficifolia might be used as an alternative medication for the control of diabetes mellitus and that it has antioxidant and anti-inflammatory properties in addition to its hypoglycemic activity.

SU-E-I-78: Neuromelanin in the Subthalamic Nucleus of Patients with Parkinson's Disease: An Electron Spin Resonance Spectroscopy Study

PURPOSE

Parkinson disease and related syndromes are associated directly with the concentrations of neuromelanin, iron and other heavy metals, and nowadays it is discussed the possible protective role of neuromelanin by the sequester redox active iron ions, reducing the formation of free hydroxyl radicals and therefore inactivating the iron ions that induce oxidative stress. The aim of this work is to study the concentration ratios between iron ions and neuromelanin in subthalamic nucleus of patients with Parkinson's disease (PD) using Electron Spin Resonance (ESR).

METHODS

Necropsy samples of subthalamic nucleus from eight human brains were studied: three non-affected by any neurodegenerative disease and five with Parkinson's disease. The samples were stored in formaldehyde and washed with a solution of 0.01 molar of ethylenediaminetetraacetic acid. ESR experiments were development in a JEOL FA-200 X-Band spectrometer at different temperatures between -170° C to room temperature. The relative concentrations of each species were estimated from the double integral values of the fitted spectra.

RESULTS

For all samples, ESR spectra showed to be composed of three different signals following the Curie's law. One signal was attributed to high-spin ferric ions (g∼ 4.3) in rhomboedric symmetry, Cu(II) ions (close to g=2.0) and neuromelanin (g∼ 2.01). The ferric ions concentration ratio between patients and controls was 3.0±0.2. The same ratio for neuromelanine was 0.24±0.06.

CONCLUSIONS

Our preliminary results indicated a significant increment of iron concentration in PD samples which agrees with previous histochemical and biochemical reports. This finding and the clear reduction of neuromelanin concentration in PD samples suggest the possible role of neuromelanin as iron ions storage.

Measurement of the neutron radius of 208Pb through parity violation in electron scattering

We report the first measurement of the parity-violating asymmetry A(PV) in the elastic scattering of polarized electrons from 208Pb. A(PV) is sensitive to the radius of the neutron distribution (R(n)). The result A(PV)=0.656±0.060(stat)±0.014(syst) ppm corresponds to a difference between the radii of the neutron and proton distributions R(n)-R(p)=0.33(-0.18)(+0.16) fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.

Dental fluorosis, dental caries, and quality of life factors among schoolchildren in a Colombian fluorotic area

OBJECTIVE

To assess dental fluorosis, dental caries and quality of life factors associated with dental fluorosis among schoolchildren living in a Colombian endemic dental fluorosis area.

METHOD

110 12-year olds were visually examined for dental caries (ICDAS) and dental fluorosis (TF) and a self-administered quality of life and fluorosis questionnaire was applied.

RESULTS

The prevalence of dental fluorosis reached 100% in this sample with most children falling within the TF 3 severity category. Varying degrees of severity were observed as follows for TF 1 to 6: 1%, 16%, 62%, 16%, 4%, 2%. The prevalence of caries experience (DF-S2) was 54%. The DF-S2 mean was 4.4 (sd 4.3). The principal contributor to the DF-S2 outcome was the decayed component. When initial caries lesions were included (ICDAS-scores 1-3) the mean DF-S1,2 increased to 10 (sd 5.1). The association between fluorosis and dental caries was not statistically significant (p > 0.05). Children not only detected the presence of something abnormal in their teeth but also reported feeling embarrassed, and worried due to their dental appearance. Almost 60% of the children reported avoiding smiling because of their teeth's appearance.

CONCLUSIONS

The high prevalence of dental fluorosis and dental caries combined with the schoolchildren's negative perception about their dental health reflects the need to propose effective dental public health policies to regulate multiple exposures to fluoride at an early age, and to improve health outcomes in a highly vulnerable population.

Infiltrating/sealing proximal caries lesions: a 3-year randomized clinical trial

This randomized split-mouth controlled clinical trial aimed at assessing the therapeutic effects of infiltration vs. sealing for controlling caries progression on proximal surfaces. Out of 90 adult students/patients assessed at university clinics and agreeing to participate, 39, each with 3 proximal lesions identified radiographically around the enamel-dentin junction to the outer third of the dentin, were included. Lesions were randomly allocated for treatment to test-A (Infiltration: ICON-pre-product; DMG), test-B (Sealing: Prime-Bond-NT; Dentsply), or control-C (Placebo). Primary outcome after 1, 2, and 3 yrs of radiographically observed lesion progression was assessed by an independent examiner blinded to groups, using pair-wise and digital-subtraction readings. No adverse events occurred. In 37 participants assessed after 3 yrs, 10 lesions (A-4; B-2; C-4) progressed deep into dentin and needed operative treatment. The 3-year therapeutic effect, based on pair-wise radiographic readings between infiltration and placebo, was 37.8% (95% CI: 20.5-55.2%) and that between sealing and placebo was 29.7% (95% CI: 20.2-35.0%). One-year follow-up digital-subtraction readings showed significant differences in lesion progression between infiltration and placebo (P = 0.0012) and between sealing and placebo (P = 0.0269). The study showed that infiltration and sealing are significantly better than placebo treatment for controlling caries progression on proximal lesions. No significant difference was seen between infiltration and sealing (ClinicalTrials.gov number NCT01417832).

Search for a new gauge boson in electron-nucleus fixed-target scattering by the APEX experiment

We present a search at the Jefferson Laboratory for new forces mediated by sub-GeV vector bosons with weak coupling α' to electrons. Such a particle A' can be produced in electron-nucleus fixed-target scattering and then decay to an e + e- pair, producing a narrow resonance in the QED trident spectrum. Using APEX test run data, we searched in the mass range 175-250 MeV, found no evidence for an A'→ e+ e- reaction, and set an upper limit of α'/α ~/= 10(-6). Our findings demonstrate that fixed-target searches can explore a new, wide, and important range of masses and couplings for sub-GeV forces.

Non-cryogenic anatomical imaging in ultra-low field regime: hand MRI demonstration

Ultra-low field (ULF) MRI with a pulsed prepolarization is a promising method with potential for applications where conventional high-, mid-, and low-field medical MRI cannot be used due to cost, weight, or other restrictions. Previously, successful ULF demonstrations of anatomical imaging were made using liquid helium-cooled SQUIDs and conducted inside a magnetically shielded room. The Larmor frequency for these demonstrations was ∼3 kHz. In order to make ULF MRI more accessible, portable, and inexpensive, we have recently developed a non-cryogenic system. To eliminate the requirement for a magnetically shielded room and improve the detection sensitivity, we increased the frequency to 83.6 kHz. While the background noise at these frequencies is greatly reduced, this is still within the ULF regime and most of its advantages such as simplicity in magnetic field generation hardware, and less stringent requirements for uniform fields, remaining. In this paper we demonstrate use of this system to image a human hand with up to 1.5mm resolution. The signal-to-noise ratio was sufficient to reveal anatomical features within a scan time of less than 7 min. This prototype can be scaled up for constructing head and full body scanners, and work is in progress toward demonstration of head imaging.

Short range correlations and the EMC effect

This Letter shows quantitatively that the magnitude of the EMC effect measured in electron deep inelastic scattering at intermediate x(B), 0.35≤x(B)≤0.7, is linearly related to the short range correlation (SRC) scale factor obtained from electron inclusive scattering at x(B)≥1. The observed phenomenological relationship is used to extract the ratio of the deuteron to the free pn pair cross sections and F(2)(n)/F(2)(p), the ratio of the free neutron to free proton structure functions. We speculate that the observed correlation is because both the EMC effect and SRC are dominated by the high virtuality (high momentum) nucleons in the nucleus.

Level-set segmentation of pulmonary nodules in megavolt electronic portal images using a CT prior

PURPOSE

Pulmonary nodules present unique problems during radiation treatment due to nodule position uncertainty that is caused by respiration. The radiation field has to be enlarged to account for nodule motion during treatment. The purpose of this work is to provide a method of locating a pulmonary nodule in a megavolt portal image that can be used to reduce the internal target volume (ITV) during radiation therapy. A reduction in the ITV would result in a decrease in radiation toxicity to healthy tissue.

METHODS

Eight patients with nonsmall cell lung cancer were used in this study. CT scans that include the pulmonary nodule were captured with a GE Healthcare LightSpeed RT 16 scanner. Megavolt portal images were acquired with a Varian Trilogy unit equipped with an AS1000 electronic portal imaging device. The nodule localization method uses grayscale morphological filtering and level-set segmentation with a prior. The treatment-time portion of the algorithm is implemented on a graphical processing unit.

RESULTS

The method was retrospectively tested on eight cases that include a total of 151 megavolt portal image frames. The method reduced the nodule position uncertainty by an average of 40% for seven out of the eight cases. The treatment phase portion of the method has a subsecond execution time that makes it suitable for near-real-time nodule localization.

CONCLUSIONS

A method was developed to localize a pulmonary nodule in a megavolt portal image. The method uses the characteristics of the nodule in a prior CT scan to enhance the nodule in the portal image and to identify the nodule region by level-set segmentation. In a retrospective study, the method reduced the nodule position uncertainty by an average of 40% for seven out of the eight cases studied.

Measurements of the electric form factor of the neutron up to Q2=3.4 GeV2 using the reaction 3He(e,e'n)pp

The electric form factor of the neutron was determined from studies of the reaction 3He(e,e'n)pp in quasielastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the Q2 range over which it is known, we find G(E)(n)=0.0236±0.0017(stat)±0.0026(syst), 0.0208±0.0024±0.0019, and 0.0147±0.0020±0.0014 for Q(2)=1.72, 2.48, and 3.41 GeV2, respectively.

Abstract P6-04-16: Molecular Profiling of Stage II and III Breast Cancer in Latin American Women Receiving Standard-of-Care Treatment

Breast cancer, though genetically and clinically heterogeneous, still lacks reliable prognostic and predictive markers. Gene expression profiling studies have correlated with long-term survival and response to therapy. Multiple variables thought to modify gene expression (i.e., ancestry, socio-economical and cultural factors) are not always controlled when correlating molecular markers with clinical outcome. Breast cancer rates are lower in Latin America than in other countries; molecularly, variations in gene expression should reflect different genetic and epigenetic levels there. The United States-Latin America Cancer Research Network (US-LA CRN) launches its first breast cancer pilot study in 2010 in over 20 hospitals and research facilities across Argentina, Brazil, Chile, Mexico, and Uruguay, primarily to characterize molecular profile distribution (luminal A, luminal B, HER2-like, and basal) in Latin American women with non-metastatic stage II or III breast cancer. Molecular profiles determined by microarray will be correlated with epidemiological, histological, and clinical data, including pathologic response to standard neoadjuvant chemotherapy; a molecular signature that predicts response to neoadjuvant therapy in breast cancer will be defined. This prospective cohort study will not dispense investigational drugs. Part A characterizes molecular profiles of breast cancer in Latin America; Part B examines associations between response to neoadjuvant therapy and molecular profiles. Tissue samplesfor gene expression profiling will be collected during routine core biopsies or during surgery. Core biopsies and surgical resection specimens from participants will undergo histopathologic evaluation, tumor ER, PgR, HER2, and Ki67 status assessment. During Part B, patients will be sorted by hormone receptor and HER2 status and receive standard neoadjuvant chemotherapy. Tissue samples will be re-assessed to evaluate residual cancer burden for pathologic response to neoadjuvant treatment and gene expression. Five-year patient follow-up will determine associations between molecular profiles and disease evolution after standard treatment. Besides providing data on the effectiveness of standard chemotherapy in Latin American women, study infrastructure includes establishing biobanks in participating countries to conduct additional clinical trials incorporating complex genomic and pathologic biomarkers, including trials to evaluate investigational therapies.

Studying the molecular profile of breast cancer in Latin America will improve diagnosis and treatment, correlate molecular subtypes with long-term survival and response to therapy, and identify indolent-disease subpopulations of cancer patients, perhaps enabling future personalized cancer management.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-04-16.

Sealing distal proximal caries lesions in first primary molars: efficacy after 2.5 years

BACKGROUND

The prevalence of proximal caries in primary molar teeth is high in many countries.

AIMS

(1) To study by means of a split-mouth design the 1- and 2.5-year efficacy of sealing proximal lesions vs. flossing instructions (control) on primary molar teeth. (2) To assess children's behaviour and pain perception during the procedure.

METHODS

Ninety-one 4- to 6-year-old children from Bogotá, Colombia participated. Participants had to have at least two proximal lesions scored according to the following radiographic classification system: radiolucency (1) in enamel outer half, (2) restricted to enamel-dentine junction, or (3) restricted to dentine outer third. Baseline, 1- and 2.5-year follow-up bitewing radiographs were taken. Test and control lesions were randomly selected. After temporary separation test lesions were sealed (adhesive). Parents/caregivers received a flossing leaflet for their children. Progression of the lesions was assessed by means of independent reading of conventional bitewing radiographs.

RESULTS

One-year (n = 73) test vs. control lesion progression was 27.4 vs. 50.7%, respectively (p < 0.01, McNemar's test), and 2.5-year (n = 56) test vs. control lesion progression was 46.4 vs. 71.4%, respectively (p < 0.01). The dropouts did not differ from those who remained in the study regarding relevant caries baseline data. More than 88% of the participants presented positive to definitively positive behaviour and very low or low pain intensity at both first and second appointments.

CONCLUSION

The sealing technique was superior to flossing instructions both after 1 and 2.5 years of follow-up and the majority of the participants had no anxiety or pain during the treatment.

Effects of food deprivation and particle size of ground wheat on digestibility of food components in broilers fed on a pelleted diet

The first aim of the experiment was to study the effect of wheat (Triticum aestivum) particle size on the digestibility of starch in a pelleted diet given to broilers. The second aim was to study the consequences of food deprivation before the excreta collection period (from 21 to 24 d). Wheat from a strong hardness cultivar was incorporated at 546.1 g/kg in diets. The other main ingredients were soybean meal (353.5 g/kg) and rapeseed oil (55.0 g/kg). Diets were given as pellets. The experimental design was a 2 x 2 factorial design testing two particle sizes of wheat flour and two procedures of a balance experiment (with or without food deprivation). Birds given diet C (wheat coarse grinding before pelleting) had significantly greater gizzard weight than birds fed on diet F (wheat fine grinding before pelleting). Starch digestibility value was significantly increased when birds were fed on diet F. This effect was halved by food deprivation. No significant effect of grain particle size was observed for protein and lipid digestibility values. However, food deprivation decreased apparent protein digestibility, with an effect which was more pronounced for fine than for coarse grinding. AMEN of the diet was significantly improved by fine grinding of wheat and decreased by food deprivation. However, no significant differences in growth performance were induced by differences in wheat grinding. No significant effect of grinding was observed on the water excretion:feed intake ratio. No significant difference was observed for vent score between treatments. There was over-excretion of starch in the first hours of refeeding following food deprivation.

Soft wheat instead of hard wheat in pelleted diets results in high starch digestibility in broiler chickens

(1) The aim of the experiment was to re-examine variations in digestibilities of food components in 3-week-old broiler chickens fed on pelleted diets based on wheats differing in lipase activity and hardness. Fourteen wheat (Triticum aestivum) samples, each from a different cultivar, were included at 550 g/kg in 14 different diets given to male Ross broiler chicks from 7 d of age. The other main ingredients consisted of soyabean meal (353 g/kg) and rapeseed oil (55 g/kg). A 15th diet containing durum wheat (Triticum durum) was also tested. (2) Hardness of wheats (Triticum aestivum) varied between 14 (very soft) and 88 (very hard), and lipase activity of wheats varied from 1 to 13.1 (relative scale). No significant correlation was found between in vitro viscosities and other parameters such as hardness, particle size of wheat flours and lipase. Hardness was correlated with the mean particle size of wheat flours and durability of pellets. (3) Individual lipid digestibilities were negatively correlated with in vitro viscosities of wheats. (4) Individual starch digestibilities were negatively correlated with wheat hardness, particle size of wheat flour before pelleting, and pellet durability. The ratio of measured AME(N) to predicted AME(N) was also negatively correlated with wheat hardness. Simple regression calculation showed that a 100-point increase in wheat hardness resulted in a 3% decrease in the AME(N) value of diets. Multiple regression calculation showed the food/gain ratio (d 10 to d 21) to be positively related to wheat hardness and negatively related to pellet durability. (5) Wheat lipase activity was positively correlated with individual starch digestibility, which was the reverse of a result obtained in a previous experiment. Thus, wheat lipase activity did not seem consistent for predicting starch digestibility and AME(N) values. (6) Among all wheat samples, durum wheat showed the highest protein content and the lowest content of water-insoluble cell-wall. Starch digestibility of durum wheat tended to be lower than that of other wheats (0.916 vs 0.936). However, no significant difference in AME(N) was observed between the durum wheat sample and other wheats. (7) Gut morphometric data measured at d 24 did not show significant differences between dietary treatments.

Probing quark-gluon interactions with transverse polarized scattering

We have extracted QCD matrix elements from our data on doubly polarized inelastic scattering of electrons on nuclei. We find the higher twist matrix element d˜2, which arises strictly from quark-gluon interactions, to be unambiguously nonzero. The data also reveal an isospin dependence of higher twist effects if we assume that the Burkhardt-Cottingham sum rule is valid. The fundamental Bjorken sum rule obtained from the a0 matrix element is satisfied at our low momentum transfer.

Assessment of symptoms during gastric emptying scintigraphy to correlate symptoms to delayed gastric emptying

BACKGROUND

Symptoms of gastroparesis based on patient recall correlate poorly with gastric emptying. The aim of this study is to determine if symptoms recorded during gastric emptying scintigraphy (GES) correlate with gastric emptying and with symptoms based on patient recall.

METHODS

Patients undergoing GES completed the Patient Assessment of GI Symptoms (PAGI-SYM) assessing symptoms over the prior 2 weeks and a questionnaire for which patients graded six symptoms during GES. A Symptom Severity Index (SSI) represented the mean of six symptoms at each time point.

KEY RESULTS

A total of 560 patients underwent GES for clinical evaluation of symptoms. Of 388 patients included in the study: 232 patients had normal GES (NGES), 156 delayed GES (DGES), and 11 rapid GES (RGES). Symptom severity index increased pre to postprandial for each group: NGES: 0.51 +/- 0.07 to 0.92 +/- 0.03, DGES: 0.60 +/- 0.09 to 1.13 +/- 0.05, and RGES: 0.56 +/- 0.12 to 0.79 +/- 0.13. Delayed gastric emptying scintigraphy patients had a higher postprandial SSI than NGES patients (1.13 +/- 0.05 vs 0.92 +/- 0.03, P < 0.05). Postprandial symptoms of stomach fullness (1.9 +/- 0.12 vs 1.5 +/- 0.09; P = 0.011), bloating (1.4 +/- 0.11 vs 1.1 +/- 0.09; P = 0.033), and abdominal pain (1.1 +/- 0.08 vs 0.7 +/- 0.12; P = 0.012) were higher in DGES than NGES. Symptom severity based on PAGI-SYM for 2 weeks prior to GES correlated with symptoms during the test for nausea (NGES, r = 0.61; DGES, r = 0.70), stomach fullness (NGES, r = 0.47; DGES, r = 0.60), and bloating (NGES, r = 0.62, DGES, r = 0.66).

CONCLUSIONS & INFERENCES

Stomach fullness, bloating, and abdominal pain recorded during GES were higher in patients with delayed gastric emptying than in patients with normal gastric emptying. Symptoms recorded during GES correlated with those during daily life by patient recall.

Hair analysis versus conventional methods of drug testing in substance abusers seeking organ transplantation

As substance abusers need to demonstrate abstinence prior to transplant, valid/reliable drug tests are needed. Patients may deny use, fearing surgery will be delayed. Breath, blood and urine tests have brief detection windows that allow patients to evade detection. Routine laboratory tests do not include all substances of abuse. Hair analysis overcomes these barriers, increasing the likelihood that active users will be identified. This study compared results for alcohol, opioids and cocaine based on 445 self-report, breath, urine and hair samples from 42 patients who had been denied a transplant due to recent substance abuse. Compared to hair toxicology, sensitivity for conventional drug tests was moderate for cocaine and opioids, but poor for alcohol. Of positive hair tests, only half were corroborated through other tests. In contrast, specificity was high across tests and substances, with positive findings from conventional tests confirmed through hair toxicology. Based on a 90-day detection window for hair analysis, two negative tests suggest 6 months of continuous abstinence. Hair testing should be considered as an alternative approach for monitoring substance use in the transplant population, either as a routine procedure or when the veracity of findings from conventional tests is in doubt.

Epidemiological study of canine trypanosomosis in an urban area of Ivory Coast

Following confirmed cases of trypanosomosis in military working dogs, a cross-sectional study was undertaken to evaluate the source of infection and determine the prevalence of canine infection with Trypanosoma congolense in the urban focus of Abidjan, Ivory Coast. Blood from 123 dogs were collected and subjected to PCR using specific primers for Trypanosoma congolense "forest type". In addition, an entomological study was conducted in an urban area near the forest surronding the military camp. The observed prevalence was 30.1% and PCR positivity to Trypanosoma congolense was not significantly associated with sex or age of animals. This study demonstrates the high contamination rate of dogs in enzootic zones, the potential risk of introduction of the disease in free animal populations and the ability of Glossina palpalis to adapt to urban areas and to transmit trypanosomosis in such areas. The factors leading to a possible emergence of canine trypanosomiasis in enzootic zones need further investigations.

Effect of anaesthesia of the palmar digital nerves on proximal interphalangeal joint pain in the horse

REASONS FOR PERFORMING STUDY

Anaesthesia of the palmar digital nerves is claimed to attenuate lameness in some horses that are lame because of pain in the proximal interphalangeal (PIP) joint.

OBJECTIVE

To determine the response of horses with pain in the PIP joint to anaesthesia of the palmar digital nerves.

METHODS

Horses were video recorded trotting before and after induction of pain in the PIP joint and 10 mins after anaesthesia of the palmar digital nerves. The palmar digital nerves were anaesthetised 3 times at different sites, and the video recorded gaits were scored subjectively.

RESULTS

The median lameness score of gaits after administration of 2% mepivacaine 1 cm proximal to the cartilages of the foot was not significantly different from the median lameness score before anaesthesia of the palmar digital nerves (P > or = 0.05), although that of 1 of 6 horses improved markedly. The median lameness score was significantly (P < or = 0.05) improved after mepivacaine was administered 2 and 3 cm proximal to the cartilages of the foot.

CONCLUSIONS

The PIP joint is unlikely to be anaesthetised when the palmar digital nerves are anaesthetised at the proximal margin of the cartilages of the foot.

POTENTIAL RELEVANCE

Pain within the PIP joint cannot be excluded as a cause of lameness when lameness is attenuated by anaesthesia of the palmar digital nerves at any site proximal to the proximal margin of the cartilages of the foot.

BME education program and research activities at the National Autonomous University of Mexico (UNAM)

Biomedical engineering at the Universidad Nacional Autónoma de Mexico (UNAM - National Autonomous University of Mexico) has been developing slowly compared to other local universities. A BME-closing module was established as an elective one for the bachelors of electronic and computer engineering degrees and it has been offered recently. This approach enables the students to apply the principles of physics and engineering in a biomedical context. The popularity of the BME-closing module is growing and more students are opting for this module. This paper presents the BME activities at the UNAM and the experience of the elective module.

High-resolution spectroscopy of Lambda16N by electroproduction

An experimental study of the (16)O(e,e'K(+))(Lambda)(16)N reaction has been performed at Jefferson Lab. A thin film of falling water was used as a target. This permitted a simultaneous measurement of the p(e,e'K(+))Lambda, Sigma(0) exclusive reactions and a precise calibration of the energy scale. A ground-state binding energy of 13.76+/-0.16 MeV was obtained for (Lambda)(16)N with better precision than previous measurements on the mirror hypernucleus (Lambda)(16)O. Precise energies have been determined for peaks arising from a Lambda in s and p orbits coupled to the p(1/2) and p(3/2) hole states of the (15)N core nucleus.