Symposium review: Recent advances in dairy food safety research: An overview of the National Dairy Council Listeria Consortium, industry identification, and funding of research gaps.

Consumers should have confidence that dairy foods are safe to eat. The Food Safety Committee of the Innovation Center for US Dairy (IC), created in 2010 to help processors collectively improve practices and reduce risks in dairy foods, is an industry-wide food safety collaboration that aims to protect the public through its mission to "Strengthen manufacturing practices in all dairy processing facilities and advance science-based tools to diminish food safety risks that could compromise the reputation of the U.S. dairy industry." The IC Listeria Research Consortium, a subset of the IC Food Safety Committee, funds research directed at creating new tools and practices to control Listeria in finished products and in manufacturing plants. This synopsis summarizes a presentation on the work conducted by the IC Food Safety Committee and research funded by the IC Listeria Research Consortium that was part of a symposium highlighting recent scientific findings and potential practical approaches to better control Listeria using science-based tools.

Keratinocyte cytogenetics in 10 patients with pigmentary mosaicism: identification of one case of trisomy 20 mosaicism confined to keratinocytes.

BACKGROUND: Hypomelanosis of Ito and linear and whorled hypermelanosis are pigmentary disorders that follow Blaschko's lines and are associated with cytogenetic mosaicism. However, mosaicism cannot always be shown using conventional karyotyping of blood lymphocytes or skin fibroblasts. This may be because these cell lines originate from mesoderm, whereas Blaschko's lines are an ectodermal phenomenon. OBJECTIVES: To investigate the diagnostic value of keratinocyte cytogenetics in patients with pigmentary mosaicism (PM). METHODS: We undertook a prospective study of 10 patients with clinically suspected PM. Previous karyotyping of blood, and in some cases skin fibroblasts, was normal in all cases. Keratinocytes and fibroblasts were cultured from skin biopsies taken from light and dark skin, and examined for cytogenetic abnormalities. RESULTS: In 9 of 10 cases both keratinocyte and fibroblast cytogenetic analyses were normal. The remaining patient showed trisomy 20 mosaicism confined to keratinocytes from hypopigmented skin. Fluorescent in situ hybridization using a probe for 20q confirmed trisomy 20 mosaicism in keratinocytes but not fibroblasts, with higher signal expression in hypopigmented compared with normal skin. CONCLUSIONS: In patients with clinically suspected PM but normal blood cytogenetics, keratinocytes may be more sensitive than skin fibroblasts in identifying cytogenetic mosaicism in selected patients. However, the additional diagnostic yield appears to be insufficient to justify routine keratinocyte cytogenetic investigation. Our findings indirectly support the hypothesis that Blaschko's lines delineate the embryonal migration paths taken by ectodermal cells including keratinocytes and melanocytes.

Lunar soil hydration constrained by exospheric water liberated by meteoroid impacts.

Analyses of samples from the Apollo missions suggest that the Moon formed devoid of native water. However, recent observations by Cassini, Deep Impact, Lunar Prospector and Chandrayaan-1 indicate the existence of an active water cycle on the Moon. Here we report observations of this water cycle, specifically detections of near-surface water released into the lunar exosphere by the Neutral Mass Spectrometer on the Lunar Atmosphere and Dust Environment Explorer. The timing of 29 water releases is associated with the Moon encountering known meteoroid streams. The intensities of these releases reflect the convoluted effects of the flux, velocity and impact location of the parent streams. We propose that four additional detected water releases represent the signature of previously undiscovered meteoroid streams. We show that water release from meteoroid impacts is indicative of a lunar surface that has a desiccated soil layer of several centimetres on top of uniformly hydrated soil. We infer that the Moon is currently in the process of losing water that was either delivered long ago or present at its formation.

Lunar atmosphere. How surface composition and meteoroid impacts mediate sodium and potassium in the lunar exosphere.

Despite being trace constituents of the lunar exosphere, sodium and potassium are the most readily observed species due to their bright line emission. Measurements of these species by the Ultraviolet and Visible Spectrometer (UVS) on the Lunar Atmosphere and Dust Environment Explorer (LADEE) have revealed unambiguous temporal and spatial variations indicative of a strong role for meteoroid bombardment and surface composition in determining the composition and local time dependence of the Moon's exosphere. Observations show distinct lunar day (monthly) cycles for both species as well as an annual cycle for sodium. The first continuous measurements for potassium show a more repeatable variation across lunations and an enhancement over KREEP (Potassium Rare Earth Elements and Phosphorus) surface regions, revealing a strong dependence on surface composition.

Depressor action of insulin on skeletal muscle vasculature: a novel mechanism for postprandial hypotension in the elderly.

OBJECTIVES: We sought to assess the role of insulin in postprandial blood pressure regulation in the elderly. BACKGROUND: Insulin is both a positive inotropic and chronotropic hormone that also vasodilates skeletal muscle vasculature. Insulin may thus mediate aspects of postprandial cardiovascular homeostasis. METHODS: Ten healthy elderly subjects were studied in the fasting state on three separate days. After baseline supine hemodynamic and neurohumoral measurements were taken (cardiac output and superior mesenteric artery blood flow were measured using Doppler ultrasound, and calf blood flow was measured using venous occlusion plethysmography), subjects ate on one occasion a 2.5-MJ high carbohydrate meal and on the other two occasions, an isoenergetic high fat meal. One high fat meal was accompanied by an insulin infusion reproducing the plasma insulin profile seen after a high carbohydrate meal while maintaining the glycemic profile seen after a high fat meal alone. After meal ingestion, measurements were repeated every 20 min for 2 h. RESULTS: After the three meals, there were similar increments in cardiac output and heart rate. After the high carbohydrate meal and high fat meal with insulin, mean arterial blood pressure fell by between 8 to 10 mm Hg, but did not change after the high fat meal. After the high carbohydrate meal and the high fat meal with insulin, calf vascular resistance did not change, whereas after the high fat meal, it increased by 15.5 +/- 4.4 U (mean +/- SEM). CONCLUSIONS: Insulin contributes to the failure of calf vasoconstriction seen after a high carbohydrate meal. By this vasodepressor action, insulin is at least in part responsible for the fall in blood pressure after a high carbohydrate meal.

Use of the TDx-FLM assay in evaluating fetal lung maturity in an insulin-dependent diabetic population. The Diabetes and Fetal Maturity Study Group.

OBJECTIVE: To assess the usefulness of the recently introduced TDx-FLM assay in managing pregnant women with diabetes. METHODS: Participating institutions were recruited from the 1993 and 1994 Society of Perinatal Obstetricians Diabetes Special Interest Group meetings. Study patients consisted of insulin-dependent diabetic women who had undergone transabdominal amniocentesis with assay of the fluid by the TDx-FLM method. Pertinent data were requested concerning pregnancy and respiratory outcomes of the corresponding neonates. RESULTS: Data from 261 pregnancies at 13 institutions were collected. Eight of the 182 infants born within 4 days of amniocentesis developed respiratory distress syndrome (RDS); five of the eight infants with RDS required intubation, and all five had TDx-FLM values less than 70 mg of surfactant per gram of albumin. Three of the eight infants with RDS required hood oxygen only; two of these infants had TDx-FLM values at least 70 mg/g. Thirteen of 144 (9%) subjects who delivered within 4 days of amniocentesis and for whom a TDx-FLM assay and phosphatidylglycerol level were both reported had a TDx-FLM level of at least 70 mg/g and a negative phosphatidylglycerol result. No infant with this combination of results developed RDS. Fifteen of the 40 patients who delivered more than 4 days after amniocentesis, with both tests available, had TDx-FLM values at least 70 mg/g and were phosphatidylglycerol negative. CONCLUSION: In infants of diabetic mothers, TDx-FLM values at least 70 mg/g were not associated with RDS requiring intubation. The TDx-FLM assay may be useful in determining the best time of delivery for pregnant patients with diabetes, especially in a situation in which the TDx-FLM assay is mature and the phosphatidylglycerol result is immature.

Systematic and regional haemodynamic effects of caffeine and alcohol in fasting subjects.

It is well established that caffeine and alcohol can have acute effects on heart rate and blood pressure, but it is not known whether cardiac output and peripheral blood flow are also affected. Such information is needed before any possible effects of caffeine or alcohol on the haemodynamic responses to food can be assessed. Thus, the present study determined the haemodynamic effects of caffeine or alcohol. Eight healthy young subjects were studied in the fasting state before and after ingestion of water (200 ml), coffee containing caffeine (3.5 mg/kg in 200 ml) or alcohol (0.5 g/kg made up to 200 ml) , in random order on three separate occasions. All of the subjects had abstained from both caffeine and alcohol for at least 12 h. Measurements of blood pressure (BP), heart rate (HR), cardiac output (CO), superior mesenteric artery blood flow (SMABF) and calf blood flow (CBF) were made at baseline and for 2 h after each drink. With the alcohol drink, blood alcohol levels estimated using breath measurement peaked at 18.8 mmol/l. HR fell slightly after water but increased after alcohol (+ 7 beats/min) and after caffeine (+ 16 beats/min, group × time interaction analysis of variance, p < 0.03), with peak responses at 40-60 min and a return to baseline by 120 min. Systolic BP increased significantly with time after all three drinks , with no significant differences between the drinks. CBF rose slightly after the drink of water, more so after alcohol but fell slightly after caffeine (group × time interaction analysis of variance, p < 0.01). Total peripheral resistance rose slightly after water and alcohol but much more markedly after caffeine (group effect analysis of variance, p < 0.001). There were no significant effects of alcohol or caffeine on the other variables. Thus, caffeine and alcohol themselves have haemodynamic effects which might interact with the effects of food.

Factor VIII procoagulant antigen levels in normal pregnancy and preeclampsia.

It has been suggested that the basis for the marked discordance in factor VIII parameters in preeclampsia is the result of proteolysis of the factor VIII procoagulant component (VIII:C) owing to activation of the coagulation system. To investigate this further, levels were compared of factor VIII:C and VIII:C (Ag), the immunologic equivalent of the procoagulant activity, in a series of preeclamptic patients and patients with uncomplicated pregnancies. No significant difference in the mean (+/- SD) level of factor VIII:C or VIII:C (Ag) could be detected between these groups. Our results do not support proteolysis of factor VIII:C as a mechanism to account for the discordant levels of the factor VIII parameters in preeclampsia.

A new ciliary feeding structure in an ophiuroid echinoderm.

The genital shields which form the walls of the bursal slits in Ophiura texturata are covered by a precisely oriented arrangement of ciliated ridges and non-ciliated grooves. An electron microscopic examination has revealed many mucous cells associated with this structure and a catecholamine-containing nerve plexus underlying it. An examination of the currents produced by this ciliated structure suggest that it is associated with suspension feeding and preliminary results indicate that the secretion of mucus is under neural control. Specialized structures of this type have not been previously described in ophiuroids and are only present in the members of certain families. The interest in these structures is not just in relation to feeding mechanisms in ophiuroids but they also provide a useful specialized preparation for the study of some aspects of the function of the subepidermal nerves in echinoderms.

Within- and between-day variability in transcutaneous Doppler ultrasound measurements of superior mesenteric artery blood flow (SMABF) in the fasted state.

This study assessed within- and between-day variability of human superior mesenteric artery blood flow (SMABF) using transcutaneous Doppler ultrasound. Two groups of healthy volunteers were studied after fasting overnight; six subjects were studied for one visit of 90 min duration (group 1) and six other subjects attended the laboratory for three separate visits of 30 min duration (group 2). Measurements of SMABF were made by a single, trained observer every 15 min, the angle of insonation of the Doppler beam being set both < 30 degrees and > 30 degrees each time. Within a day (group 1), the angle of insonation had little effect upon SMABF measurements (values differed by less than 6%) and variability was low (mean coefficient of variation below 5%). SMABF measurements between days (group 2) were consistent (mean coefficient of variation ranging from 6 to 12%), but measurements made at angles of < 30 degrees had slightly lower standard error of the mean (SEM) and coefficient of variation (CV) than those above 30 degrees. Thus, in fasted subjects there is small within-visit or between-visit variability in SMABF assessed by a single trained observer using Doppler ultrasound. Slightly less variability is observed when scanning at angles of < 30 degrees, but this effect was not substantial and the correction factor for angle contained within the software of the ultrasound machine appeared to be reliable.

Schistocytosis, aminotransferase elevation and thrombocytopenia in preeclampsia/eclampsia.

Some preeclamptic patients have schistocytosis, abnormal liver function tests and thrombocytopenia. To determine how strongly these three abnormalities cluster with each other, a sequential series of 49 preeclamptic or eclamptic patients was analyzed for the presence of schistocytosis, serum aminotransferase elevation and thrombocytopenia. These three abnormalities were found less often together (the HELLP syndrome) than singly or in pairs. These data do not clearly separate HELLP patients from other preeclamptic patients.

Pediatric patients experiencing postoperative nausea and vomiting after burn reconstruction surgery: an analysis.

Nausea and vomiting after a surgical procedure has a significant impact on a patient's hospital course. A perceived increased incidence of postoperative nausea and vomiting (PONV) in pediatric patients undergoing reconstructive scalp surgery had been clinically observed. A chart review to determine if a relationship existed between the surgical procedure and the incidence of PONV was conducted by selecting patients who were 5 to 12 years old and whose surgery fell between April 1995 and August 1995. Thirty-eight patients were evaluated for 46 procedures; 8 patients were evaluated for both insertion and removal of scalp expanders. No differences were identified between groups for previous history of PONV, length of anesthesia, or position during surgery. Data from the retrospective review suggested that pediatric patients with reconstructive surgeries of the scalp experienced PONV at 100% (24 procedures), whereas only 45% (10 procedures) of patients whose surgeries did not involve the scalp experienced PONV. In addition, despite significant earlier return of bowel sounds, episodes of PONV and time to oral intake were also increased in the group of patients whose operations involved the scalp. On the basis of these findings, a prospective study has been initiated to determine if changes in the perioperative protocol will improve patient outcomes and reduce the incidence of PONV.

Oxytocin for labor induction.

Induction of labor has increased from 9% to 18% of all U.S. deliveries in recent years. Several useful oxytocin induction protocols are available, both from the ACOG Practice Bulletin #10 and institutional sources. Higher-dose protocols tend to result in fewer cesarean deliveries for dystocia but more "fetal distress." There is no consensus as to which protocol is best, and the clinician is advised to understand the trade-offs involved and how those trade-offs could relate to the clinician's local situation. Given the availability now of prostaglandin agents for induction with an unfavorable cervix, the advantage of less hyperstimulation in low-dose oxytocin protocols may become increasingly important. The most important risks include hyperstimulation (frequent but usually brief and well-tolerated), failed induction (occasional and important), and uterine rupture in some studies (rare but dangerous). Pain was not a sensitive indicator of uterine rupture in a large 1989 study. Fetal heart rate changes were much more likely to herald uterine rupture in that study. Oxytocin's greatest weakness is that some patients will not respond well to it, especially with marked cervical unfavorability. However, given an individual patient whose uterus will respond adequately to this drug, oxytocin has the advantage of short half-life and the option for prompt cessation if desired. Intrauterine pressure catheters with oxytocin usage are usually well-worth their minor risks. Current ACOG literature lists induction of labor in the setting of one or more previous low-transverse cesarean deliveries as necessitating "special attention" and "close patient monitoring." The well-informed clinician will be familiar with the issues involved.

The giant neurone system in Ophiuroids. I. The general morphology of the radial nerve cords and circumoral nerve ring.

The nervous system of Ophiura texturata contains nerve fibres and cell bodies that are an order of magnitude larger than anything previously described in the Asteroidea and Echinoidea. These large nerve cells are designated giant fibres. Giant nerve cells are present in both the ectoneural and hyponeural nervous system. The layout of these nerve cells is described and it is shown that the organization is repeated in each segmental ganglion that makes up the radial nerve cord. The circumoral nerve ring is composed, in the main, of tracts of nerve fibres joining the radial nerves, and it contains only limited areas of neuropil associated with the alimentary canal and muscle of the disc and jaws. Degeneration studies have shown that each segmental ganglion of the radial nerve cords contains a discrete population of neurones separate from adjacent ganglion and that there are not anatomically continuous giant fibres along the whole length of the nerve cord.

The giant neurone system in ophiuroids. III. The detailed connections of the circumoral nerve ring.

The morphology of the circumoral nerve ring of an ophiuroid, Ophiura texturata, is described. Particular attention is given to a system of fibres which are giant by echinoderm standards, and which occur both in the ectoneural and hyponeural parts of the nerve ring. The giant fibres in the ectoneurla tissue do not show the complicated pattern of distribution present in the segmental ganglia of the radial nerves. The main areas of neuropil in the ectoneural tissue are associated with small axon bundles which leave the nerve ring to innervate the gut and disc. The hyponeural tissue is exclusively motor and is involved in the innervation of the main radial and inter-radial muscles of the disc. Branches of the motor nerves are also associated with juxtaligamental tissue, the secretory products from which are thought to influence the plasticity of collagenous connective tissue. The structure of the circumoral nerve ring suggests that it serves as a functional connection between the nerve cords in adjacent radii. The ultrastructural evidence does not support the view that the circumoral nerve ring represents a central nervous system.

Systemic and regional haemodynamic effects of caffeine and alcohol in fasting subjects [corrected].

It is well established that caffeine and alcohol can have acute effects on heart rate and blood pressure, but it is not known whether cardiac output and peripheral blood flow are also affected. Such information is needed before any possible effects of caffeine or alcohol on the haemodynamic responses to food can be assessed. Thus, the present study determined the haemodynamic effects of caffeine or alcohol. Eight healthy young subjects were studied in the fasting state before and after ingestion of water (200 ml), coffee containing caffeine (3.5 mg/kg in 200 ml) or alcohol (0.5 g/kg made up to 200 ml), in random order on three separate occasions. All of the subjects had abstained from both caffeine and alcohol for at least 12 h. Measurements of blood pressure (BP), heart rate (HR), cardiac output (CO), superior mesenteric artery blood flow (SMABF) and calf blood flow (CBF) were made at baseline and for 2 h after each drink. With the alcohol drink, blood alcohol levels estimated using breath measurement peaked at 18.8 mmol/l. HR fell slightly after water but increased after alcohol (+ 7 beats/min) and after caffeine (+ 16 beats/min, group x time interaction analysis of variance, p < 0.03), with peak responses at 40-60 min and a return to baseline by 120 min. Systolic BP increased significantly with time after all three drinks, with no significant differences between the drinks. CBF rose slightly after the drink of water, more so after alcohol but fell slightly after caffeine (group x time interaction analysis of variance, p < 0.01).

Plasma fibronectin levels in preeclampsia: a possible biochemical marker for vascular endothelial damage.

Fibronectin is a plasma glycoprotein which is involved in coagulation, platelet function, tissue repair, and the vascular endothelial basement membrane. We have found plasma fibronectin concentrations to be elevated in a group of preeclamptic patients. This finding is consistent with other evidence for a role of the vascular endothelium in preeclampsia.