Determination of hydrogen cluster velocities and comparison with numerical calculations.

The use of powerful hydrogen cluster jet targets in storage ring experiments led to the need of precise data on the mean cluster velocity as function of the stagnation temperature and pressure for the determination of the volume density of the target beams. For this purpose a large data set of hydrogen cluster velocity distributions and mean velocities was measured at a high density hydrogen cluster jet target using a trumpet shaped nozzle. The measurements have been performed at pressures above and below the critical pressure and for a broad range of temperatures relevant for target operation, e.g., at storage ring experiments. The used experimental method is described which allows for the velocity measurement of single clusters using a time-of-flight technique. Since this method is rather time-consuming and these measurements are typically interfering negatively with storage ring experiments, a method for a precise calculation of these mean velocities was needed. For this, the determined mean cluster velocities are compared with model calculations based on an isentropic one-dimensional van der Waals gas. Based on the obtained data and the presented numerical calculations, a new method has been developed which allows to predict the mean cluster velocities with an accuracy of about 5%. For this two cut-off parameters defining positions inside the nozzle are introduced, which can be determined for a given nozzle by only two velocity measurements.

Genetic dissection of fruit quality traits in the octoploid cultivated strawberry highlights the role of homoeo-QTL in their control.

Fruit quality traits are major breeding targets in the Rosaceae. Several of the major Rosaceae species are current or ancient polyploids. To dissect the inheritance of fruit quality traits in polyploid fleshy fruit species, we used a cultivated strawberry segregating population comprising a 213 full-sibling F1 progeny from a cross between the variety 'Capitola' and the genotype 'CF1116'. We previously developed the most comprehensive strawberry linkage map, which displays seven homoeology groups (HG), including each four homoeology linkage groups (Genetics 179:2045-2060, 2008). The map was used to identify quantitative trait loci (QTL) for 19 fruit traits related to fruit development, texture, colour, anthocyanin, sugar and organic acid contents. Analyses were carried out over two or three successive years on field-grown plants. QTL were detected for all the analysed traits. Because strawberry is an octopolyploid species, QTL controlling a given trait and located at orthologous positions on different homoeologous linkage groups within one HG are considered as homoeo-QTL. We found that, for various traits, about one-fourth of QTL were putative homoeo-QTL and were localised on two linkage groups. Several homoeo-QTL could be detected the same year, suggesting that several copies of the gene underlying the QTL are functional. The detection of some other homoeo-QTL was year-dependent. Therefore, changes in allelic expression could take place in response to environmental changes. We believe that, in strawberry as in other polyploid fruit species, the mechanisms unravelled in the present study may play a crucial role in the variations of fruit quality.

Color Doppler ultrasound imaging in varicoceles: is the venous diameter sufficient for predicting clinical and subclinical varicocele?

PURPOSE: Investigating the diagnostic value of color Doppler ultrasound for defining the varicocele grade according to WHO criteria. METHODS: A total of 217 men (129 with clinical varicocele and 88 without clinical varicocele) were investigated by physical examination and color Doppler ultrasound and categorized according to WHO varicocele criteria (0, subclinical, I, II, and III). Diameter and reflux of the largest vein in the pampiniform plexus were measured bilaterally with the patient in the supine position in rest and during the Valsalva maneuver. To assess the possibility of differentiating varicocele grade by venous diameter, optimal cut-point values were determined by receiver-operator characteristic (ROC) analysis. RESULTS: With increased varicocele grade, a larger vein diameter was more significant in rest and during Valsalva (in all cases P < 0.05), except between grade I and grade II. Retrograde peak flow velocities were similar in every group (in all cases P > 0.1). Only grade III varicoceles demonstrated significantly increased peak flow values compared with all other grades (P < 0.001). There were no side-related differences when comparing identical varicocele grades (in all cases P > 0.1). Venous diameters above 2.45 mm in rest (sensitivity 84%, specificity 81%) or 2.95 mm during Valsalva (sensitivity 84%, specificity 84%) predicted the presence of a clinical varicocele. CONCLUSIONS: Our findings support the hypothesis that clinical varicoceles can be predicted with high accuracy based only on the diameter of testicular veins using cut-point values of >2.45 mm in rest or >2.95 mm during Valsalva maneuver in the supine position.

A novel algorithm for the determination of bacterial cell volumes that is unbiased by cell morphology.

The determination of cell volumes and biomass offers a means of comparing the standing stocks of auto- and heterotrophic microbes of vastly different sizes for applications including the assessment of the flux of organic carbon within aquatic ecosystems. Conclusions about the importance of particular genotypes within microbial communities (e.g., of filamentous bacteria) may strongly depend on whether their contribution to total abundance or to biomass is regarded. Fluorescence microscopy and image analysis are suitable tools for determining bacterial biomass that moreover hold the potential to replace labor-intensive manual measurements by fully automated approaches. However, the current approaches to calculate bacterial cell volumes from digital images are intrinsically biased by the models that are used to approximate the morphology of the cells. Therefore, we developed a generic contour based algorithm to reconstruct the volumes of prokaryotic cells from two-dimensional representations (i.e., microscopic images) irrespective of their shape. Geometric models of commonly encountered bacterial morphotypes were used to verify the algorithm and to compare its performance with previously described approaches. The algorithm is embedded in a freely available computer program that is able to process both raw (8-bit grayscale) and thresholded (binary) images in a fully automated manner.

[Argentinean consensus guidelines on the identification and clinical care of secondary progressive multiple sclerosis]. / Consenso sobre la identificación y seguimiento de la esclerosis múltiple secundaria progresiva en Argentina.

INTRODUCTION: The identification, diagnosis, follow-up, and treatment of patients with secondary progressive multiple sclerosis (SPMS) show significant differences between health care professionals in Argentina. AIM: To provide consensus recommendations on the management of patients with SPMS in Argentina to optimize patient care. DEVELOPMENT: A panel of expert neurologists from Argentina dedicated to the diagnosis and care of multiple sclerosis patients gathered during 2019 and 2020 to carry out a consensus recommendation on the diagnosis and treatment of SPMS patients in Argentina. To achieve consensus, the methodology of 'formal consensus-RAND/UCLA method' was used. Recommendations were established based on published evidence and the expert opinion. Recommendations focused on how to define SPMS and how to follow SPMS patients. CONCLUSION: The recommendations of this consensus guidelines attempt to optimize the care of SPMS patients in Argentina.

TITLE: Consenso sobre la identificación y seguimiento de la esclerosis múltiple secundaria progresiva en Argentina.Introducción. Existen diferencias significativas en el diagnóstico, la identificación y el seguimiento de pacientes con esclerosis múltiple secundaria progresiva (EMSP) entre los profesionales de la salud a cargo de su tratamiento. Objetivo. Proveer recomendaciones sobre el tratamiento de los pacientes con EMSP en Argentina con el fin de optimizar su cuidado. Desarrollo. Un grupo de neurólogos expertos en esclerosis múltiple de Argentina elaboró un consenso para el tratamiento de pacientes con EMSP en la región mediante metodología de ronda de encuestas a distancia y reuniones presenciales. Se establecieron 33 recomendaciones basadas en la evidencia publicada y en el criterio de los expertos que participaron. Las recomendaciones se enfocaron en el diagnóstico y el seguimiento de los pacientes con EMSP. Conclusión. Las recomendaciones establecidas en el presente consenso permitirían optimizar el cuidado y el seguimiento de los pacientes con EMSP en Argentina.

Automated quality assessment of autonomously acquired microscopic images of fluorescently stained bacteria.

Quality assessment of autonomously acquired microscopic images is an important issue in high-throughput imaging systems. For example, the presence of low quality images (>or=10%) in a dataset significantly influences the counting precision of fluorescently stained bacterial cells. We present an approach based on an artificial neural network (ANN) to assess the quality of such images. Spatially invariant estimators were extracted as ANN input data from subdivided images by low level image processing. Different ANN designs were compared and >400 ANNs were trained and tested on a set of 25,000 manually classified images. The optimal ANN featured a correct identification rate of 94% (3% false positives, 3% false negatives) and could process about 10 images per second. We compared its performance with the image quality assessment by different humans and discuss the difficulties in assigning images to the correct quality class. The computer program and the documented source code (VB.NET) are provided under General Public Licence.

Pseudomeningocele induced transient loss of consciousness in Marfan syndrome.

Anterior and posterior meningoceles are the severest clinical expression of dural ectasia in patients with Marfan syndrome. Meningoceles and pseudomeningoceles have been reported from either asymptomatic, to causing headache, back pain, leg pain, radiculopathy, constipation and/or urinary symptoms. This article includes a case report of a 31-year-old woman, who presented with recurrent transient loss of consciousness thought to be secondary to acute changes in intracranial pressure transmitted from a pseudomeningocele.

I know what you are doing. a neurophysiological study.

In the ventral premotor cortex of the macaque monkey, there are neurons that discharge both during the execution of hand actions and during the observation of the same actions made by others (mirror neurons). In the present study, we show that a subset of mirror neurons becomes active during action presentation and also when the final part of the action, crucial in triggering the response in full vision, is hidden and can therefore only be inferred. This implies that the motor representation of an action performed by others can be internally generated in the observer's premotor cortex, even when a visual description of the action is lacking. The present findings support the hypothesis that mirror neuron activation could be at the basis of action recognition.

Circulating somatostatin. Physiological regulator of pancreatic function?

The present study was designed to determine whether somatostatin is released into the circulation in sufficient amounts to regulate exocrine and endocrine pancreatic function and to evaluate the possible role of somatostatin as a hormonal regulator of the pancreas. Mean plasma somatostatin levels (SLI) increased from 11 +/- 2 pmol liter-1 to peak concentrations of 18 +/- 2 in six healthy male volunteers after a steak meal (P less than 0.05). Infusion of somatostatin inhibited hormone-induced exocrine pancreatic secretion and suppressed cerulein-stimulated pancreatic polypeptide (PP) secretion, but did not significantly change arginine-stimulated insulin and glucagon release at mean plasma somatostatin concentrations within the range seen after a meal. The amount of somatostatin released after a meal thus was of sufficient magnitude to inhibit exocrine pancreatic function and PP release. On the other hand, basal and arginine-stimulated glucagon and insulin secretions were not significantly affected by these plasma concentrations of intravenous somatostatin suggesting that the exocrine pancreas might be more sensitive to somatostatin than the islet cells. We conclude that somatostatin in concentrations within the range seen after a meal is a potent inhibitor of stimulated acinar cell function in man. The findings support the hypothesis that somatostatin acts as a true hormonal regulator.

Assessment of prenatal tobacco smoke exposure by determining nicotine and its metabolites in meconium.

Meconium samples collected from 115 neonates were analysed for nicotine, cotinine and trans -3-hydroxycotinine (OH-cotinine) by means of high-performance liquid chromatography (HPLC) to identify prenatal smoke exposure. The self-reported maternal smoking status during pregnancy was determined by means of a questionnaire and verified by measurements in urine prior to childbirth. The total sum of nicotine and its metabolites (Sum(tot)) of the first passed meconium samples was 1560 +/- 1024 pmol/g in newborns of smoking mothers. Smoking of less than five cigarettes was clearly detected. Sum(tot) remained constant in all meconium samples passed by a neonate in succession. However, the proportion of nicotine decreased with the time of passage after birth and the OH-cotinine proportion increased, whereas cotinine hardly changed. Nicotine or its metabolites were not detectable in meconium (detection limit < 20 pmol/g), when the mothers were only exposed to environmental tobacco smoke (ETS) using the HPLC method. The hypothesis that the content of nicotine metabolites in meconium reflects long-term smoke exposure could not be confirmed in newborns whose mothers had quit smoking during the latter half of pregnancy. Determining Sum(tot) enables the intensity of continuous smoking during pregnancy to be estimated in all meconium samples passed by a newborn.

Wadi el-Sheikh: A new archaeological investigation of ancient Egyptian chert mines.

This article provides an overview of the first results from archaeological investigations at Wadi el-Sheikh in Egypt by the University of Vienna Middle Egypt Project. Chert was an important raw material used to produce tools, implements and jewelry in ancient times. Wadi el-Sheikh was exploited over thousands of years as it was probably the most important source of chert in Pharaonic civilization. The results of our new investigations that involved surveys and test excavations indicate the presence of large scale mining activities in the first half of the 3rd Millennium B.C.E. which allow for detailed insights into the amount of raw material extracted, the mining methods used and the lithic products manufactured in this area. These aspects are contextualized on the background of ancient Egyptian state-organized resource acquisition strategies and economy.

Crystallization and preliminary X-ray studies of an aspartate aminotransferase mutant from Escherichia coli.

Mutant aspartate aminotransferase V39L (Val39 replaced by Leu) from Escherichia coli has been crystallized into a monoclinic cell from a polyethylene glycol solution (pH 7.5) by vapor diffusion. The space group and the unit cell dimensions have been determined using a precession camera, a CAD4 diffractometer and a Nicolet Xentronics area detector to be P2(1) with a = 86.8 A, b = 79.9 A, c = 89.4 A, beta = 118.74 degrees. The crystals diffract to better than 2.3 A and are suitable for X-ray structure analysis.

Electrophoretic screening for human apolipoprotein C-II variants: repeated identification of apolipoprotein C-II(K19T).

Screening for apolipoprotein (apo) C-II variants in the plasma of 400 students, 600 patients of a cardiological rehabilitation center, and 1200 patients of an outpatient lipid clinic by isoelectric focusing and subsequent anti-apo C-II immunoblotting led to the identification of four individuals whose plasma samples contained an apo C-II isoform with an abnormal isoelectric point. In all cases direct sequencing of PCR-amplified DNA assessed a heterozygous A to C transversion in codon 19 of the apo C-II gene which leads to the replacement of lysine with threonine. Two of the four index patients presented with moderate hypertriglyceridemia; one suffered from severe hyperlipidemia, with triglyceride levels ranging between 180 and 1900 mg/dl, depending on dietary changes. Sequencing of this proband's lipoprotein lipase gene showed no alteration compared to the wild-type sequence. A study in his family revealed that heterozygosity for apo C-II(K19T) is not associated with differences in mean lipid and lipoprotein concentrations. In conclusion, apo C-II(K19T) occurs in Germany at a frequency of approximately 1 in 550. Although this variant is not sufficient to cause hypertriglyceridemia, it may be possible that apo C-II(K19T) cause hypertriglyceridemia in the presence of additional as yet unidentified environmental and/or genetic factors.

Policy statement on materials for testing glucose in the urine. The Committee on Materials and Therapeutic Agents, American Diabetes Association.

Semiquantitative methods for measurement of glucose in the urine are useful for monitoring glucose homeostasis in subjects with diabetes mellitus where quantitative blood and urine glucose measurements are not available. The use of a "plus" scale for glucose measurement is confusing because the same plus values are assigned to different quantities of glucose with different methods. The two-drop Clinitest method is the most quantifiable and readable test for urine sugar, particularly if there is high sugar spill. Therefore, it is the most useful method for monitoring insulin-dependent juvenile diabetes. Its major disadvantages are its potential toxicity, the cumbersome methodology, the cost, and the possibility of interference from other reducing substances. The enzyme "dipstick" methods are most sensitive for detecting the presence of glucose. Among the available "dipstick" methods, Diastix is the most quantifiable and readable. These methods are inhibited by the presence of ketones and a number of other substances. Tes-Tape is the least expensive and, where there are inhibiting substances, the most useful, because it can be read at the liquid front where the glucose reaction is chromatographically separated. Clinistix and Chemstrip are essentially screening methods for the presence of glucose and not useful for quantification. Basing therapy on these and other plus values is irrational and should be discontinued.

Baby food exchanges and feeding the diabetic infant.

Because of the dangers of hypoglycemia to the developing brain, the need to develop a lifelong positive attitude toward an eating pattern, the inherent communication difficulties, and the spontaneity of the very young, the diabetic infant presents a particular challenge to medical personnel. Baby and toddler foods in jar measurements and formula have been translated into the American Diabetes Association exchanges to help in teaching families with diabetic infants the effects of various foods on the infant's diabetes. The exchanges are taught as tools in maintaining metabolic balance rather than as a fixed diet. Caloric level is planned on the basis of diet history and the infant's current growth status. Flexibility of pattern and attitude is emphasized to minimize conflict over eating and to allow normal spontaneous activity without jeopardizing health.

A developmentally staged curriculum for teaching self-care to the child with insulin-dependent diabetes mellitus.

A developmentally staged curriculum has been designed to teach children with insulin-dependent diabetes mellitus about their disorder and its care within an organized program of ongoing ambulatory medical care. A preliminary evaluation of the teaching program based on this curriculum indicates that self-care skills are mastered but that the implementation of self-monitoring aspects decreases during adolescence. A survey of a sampling of participants indicates that interest in the program also declines with adolescence. However, the majority had positive responses at all ages and all children and adolescents had positive responses to the experience of being with diabetic peers. The curriculum is presented to help organize the appropriate teaching of diabetes care to children and adolescents.

Impaired DNase1-mediated degradation of neutrophil extracellular traps is associated with acute thrombotic microangiopathies.

BACKGROUND: Acute thrombotic microangiopathies (TMAs) are characterized by excessive microvascular thrombosis and are associated with markers of neutrophil extracellular traps (NETs) in plasma. NETs are composed of DNA fibers and promote thrombus formation through the activation of platelets and clotting factors. OBJECTIVE: The efficient removal of NETs may be required to prevent excessive thrombosis such as in TMAs. To test this hypothesis, we investigated whether TMAs are associated with a defect in the degradation of NETs. METHODS AND RESULTS: We show that NETs generated in vitro were efficiently degraded by plasma from healthy donors. However, NETs remained stable after exposure to plasma from TMA patients. The inability to degrade NETs was linked to a reduced DNase activity in TMA plasma. Plasma DNase1 was required for efficient NET degradation and TMA plasma showed decreased levels of this enzyme. Supplementation of TMA plasma with recombinant human DNase1 restored NET-degradation activity. CONCLUSIONS: Our data indicate that DNase1-mediated degradation of NETs is impaired in patients with TMAs. The role of plasma DNases in thrombosis is, as of yet, poorly understood. Reduced plasma DNase1 activity may cause the persistence of pro-thrombotic NETs and thus promote microvascular thrombosis in TMA patients.

Evidence for muscarinic acetylcholine receptor subtypes in the pigeon telencephalon.

At least five subtypes of muscarinic acetylcholine receptors are expressed in various mammalian tissue preparations. The following experiment, through the use of direct binding assays (using tritiated quinuclidinyl benzilate), competitive binding assays (using tritiated quinuclidinyl benzilate and unlabeled pirenzepine or AF-DX 116), and autoradiographic techniques, examined whether two of these five putative muscarinic acetylcholine receptor subtypes can be found in avian brain. Accordingly, autoradiographic mapping of pirenzepine-sensitive (M1-like) and AF-DX 116-sensitive (M2-like) muscarinic acetylcholine receptor subtypes in the pigeon telencephalon was conducted. Although both ligands bound throughout the brain, most telencephalic regions, including the archistriatum, the neostriatum, and basal ganglia structures like lobus paraolfactorius, nucleus accumbens, and paleostriatum, showed a higher density of M1-like sites. The exception to this finding was the nucleus basalis which appeared as a region where M2-like sites predominated. Moreover, the telencephalic region with the largest ratio of M1-like to M2-like sites was the lateral portion of the parahippocampus; a characteristic shared with the mammalian dentate gyrus. The findings reported here are generally consistent with previous reports of mammalian M1/M2 receptor distributions.

Association of variables of coagulation, fibrinolysis and acute-phase with atherosclerosis in coronary and peripheral arteries and those arteries supplying the brain.

We investigated the vessel status of coronary and peripheral arteries and those arteries supplying the brain in 929 consecutive male patients admitted to a coronary rehabilitation unit. The severity of coronary atherosclerosis was scored using coronary angiography. Changes in extracranial brain vessels and manifest cerebrovascular disease (CVD) were determined by B-mode ultrasound and Doppler examination. Peripheral arterial disease (PAD) was diagnosed using base-line and stress oscillography. We assessed variables of coagulation, fibrinolysis, and the acute phase response. There was a significant increase in plasma fibrinogen, plasminogen, d-dimer and C-reactive protein (CRP) with increasing severity of coronary heart disease. Compared to men with unaffected arteries, men with 3 diseased coronary arteries had 58% greater d-dimer concentrations. Patients with CVD and PAD, respectively, also had significantly higher fibrinogen, d-dimer and CRP concentrations. We did not find an association between plasminogen activator inhibitor activity and the severity of coronary atherosclerosis. In conclusion, plasma fibrinogen, d-dimer and CRP concentrations were significantly related to atherosclerosis in the coronary, peripheral and extracranial brain arteries.

Association of serum apolipoprotein A-I (but not high-density lipoprotein cholesterol) with healed myocardial infarction in men independent of serum insulin and C-peptide.

Low serum levels of high-density lipoprotein (HDL) cholesterol or apolipoprotein A-I and high serum levels of insulin increase the risk of coronary heart disease (CHD) and can indicate insulin resistance. We tested the strength, independence, and interactions of associations between HDL cholesterol (or apolipoprotein A-I), insulin (or C-peptide), glucose, and CHD in 95 male nondiabetic patients with CHD who were <60 years old, in 92 probands from the PROCAM study, and in 61 non-cardiologic patients; all subjects were matched by age, body mass index, and smoking habits. Systemic hypertension (odds radio [OR] 2.8, 95% confidence intervals [CI] 1.6 to 4.8), high serum levels of glucose (OR 2.3, 95% CI 1.6 to 4.8), insulin (OR 2.1, 95% CI 1.3 to 3.6), and C-peptide (OR 4.1, 95% CI 2.2 to 7.5) as well as low serum levels of HDL cholesterol (OR 2.0, 95% CI 1.1 to 3.5) or apolipoprotein A-I (OR 3.9, 95% CI 2.1 to 7.1) had significant associations with CHD. At multivariate analysis, systolic blood pressure, glucose, apolipoprotein A-I, and C-peptide, but not HDL cholesterol and insulin, had consistent independent associations with CHD. Thus, the combined measurement of apolipoprotein A-I and C-peptide may improve the identification of nondiabetic patients at increased risk for CHD.