The 12C(n, 2n)11C cross section from threshold to 26.5 MeV.

The 12C(n, 2n)11C cross section was measured from just below threshold to 26.5 MeV using the Pelletron accelerator at Ohio University. Monoenergetic neutrons, produced via the 3H(d,n)4He reaction, were allowed to strike targets of polyethylene and graphite. Activation of both targets was measured by counting positron annihilations resulting from the ß+ decay of 11C. Annihilation gamma rays were detected, both in coincidence and singly, using back-to-back NaI detectors. The incident neutron flux was determined indirectly via 1H(n,p) protons elastically scattered from the polyethylene target. Previous measurements fall into upper and lower bands; the results of the present measurement are consistent with the upper band.

Childhood predictors of written expression in late adolescents with 22q11.2 deletion syndrome: a longitudinal study.

BACKGROUND: 22q11.2 deletion syndrome (22q11DS) is the second most prevalent genetic syndrome and has a characteristic academic and behavioural phenotype. The primary objective of the current study was to examine the childhood predictors of written expression achievement in adolescents with 22q11DS. Written expression is an important skill that can impact an individual's overall academic performance, potentially resulting in increased levels of stress and exacerbation of psychiatric symptoms. METHODS: A total of 119 participants were included in this study. Sixty-nine late adolescents with 22q11DS and 50 controls (consisting of a combined sample of 23 unaffected siblings of youth with 22q11DS and 27 community controls) participated in a 6-year longitudinal research project and received neuropsychological test batteries every 3 years. The Written Expression subtest of the Wechsler Individual Achievement Test - Second Edition was the primary outcome measure in the current project. RESULTS: Findings indicated differences in childhood predictors of adolescent written expression between participants in the 22q11DS group and participants in the control group. Whereas childhood verbal IQ scores predicted adolescent written expression for participants in the control group, childhood executive function and language skills were unique predictors of adolescent written expression in individuals with 22q11DS. CONCLUSIONS: Childhood predictors of late adolescent written expression in 22q11DS differ in meaningful ways from predictors in the non-22q11DS population. These results offer some guidance on the underlying factors that may be useful to consider when developing written expression interventions for children with 22q11DS.

[Switzerland eliminates measles. National Strategy for the Elimination of Measles 2011-2015]. / Die Schweiz eliminiert die Masern. Nationale Strategie zur Masernelimination 2011-2015.

The measles virus circulates within Switzerland in an endemic way leading to sporadic outbreaks. The most recent outbreak occurred in 2011. It lasted 9 months and had 687 reported cases. This is in contrast to 2012 when there were 66 cases,corresponding to an incidence of 8 cases per million inhabitants. During 2008-2010, the average national vaccination coverage for one or two doses of measles vaccine amounted to 92 and 83 % for 2-year-olds, 95 and 85 % for 8-year-olds, and 95 and 85 % for 16-year-olds, respectively. To improve the national vaccination coverage, the Federal Council adopted the National Strategy for the Elimination of Measles 2011-2015 in 2011.The strategy was drawn up in a participative process led by the Federal Office for Public Health.The cantons as key partners were represented by the Conference of the Cantonal Directors for Public Health and the Association of Cantonal Health Officers. The strategy pursues the vision of eliminating measles in Switzerland in order to protect the population against measles and its complications, including all persons who may not be vaccinated for medical reasons. The strategy comprises six axes of intervention:(1)political engagement and support by all stakeholders, (2)a targeted ≥ 95 % two-dose vaccination coverage for all 2-year-olds, (3)easier access and incentives for the booster vaccination for everyone in the 2-year-old age group up to those born in 1964, (4)communication and promotion, (5)uniform national outbreak control, and (6)targeted surveillance.

Network correlates of disease severity in multiple system atrophy.

OBJECTIVE: Multiple system atrophy (MSA), the most common of the atypical parkinsonian disorders, is characterized by the presence of an abnormal spatial covariance pattern in resting state metabolic brain images from patients with this disease. Nonetheless, the potential utility of this pattern as a MSA biomarker is contingent upon its specificity for this disorder and its relationship to clinical disability in individual patients. METHODS: We used [(18)F]fluorodeoxyglucose PET to study 33 patients with MSA, 20 age- and severity-matched patients with idiopathic Parkinson disease (PD), and 15 healthy volunteers. For each subject, we computed the expression of the previously characterized metabolic covariance patterns for MSA and PD (termed MSARP and PDRP, respectively) on a prospective single-case basis. The resulting network values for the individual patients were correlated with clinical motor ratings and disease duration. RESULTS: In the MSA group, disease-related pattern (MSARP) values were elevated relative to the control and PD groups (p < 0.001 for both comparisons). In this group, MSARP values correlated with clinical ratings of motor disability (r = 0.57, p = 0.0008) and with disease duration (r = -0.376, p = 0.03). By contrast, MSARP expression in the PD group did not differ from control values (p = 1.0). In this group, motor ratings correlated with PDRP (r = 0.60, p = 0.006) but not with MSARP values (p = 0.88). CONCLUSIONS: MSA is associated with elevated expression of a specific disease-related metabolic pattern. Moreover, differences in the expression of this pattern in patients with MSA correlate with clinical disability. The findings suggest that the MSARP may be a useful biomarker in trials of new therapies for this disorder.

[Macular hole surgery with air tamponade. Does air suffice for short-term tamponade?]. / Makulalochchirurgie mit Lufttamponade: Ist Luft als kurzzeitige Tamponade ausreichend?

BACKGROUND AND PURPOSE: We used a specially designed optical coherence tomography (OCT) device to investigate the dynamics of early macular hole closure after vitrectomy with air tamponade and to determine the closure rate and the briefest possible prone positioning. METHODS: A total of 112 patients with macular holes were examined using a modified spectral-domain OCT on days 1, 2 and 3 after vitrectomy with air tamponade. As soon as closure was complete (group one) or partial (hole closed at inner retinal layers but outer retinal layers still detached from pigment epithelial layer, group two), prone positioning was ended. If neither partial nor complete closure was observed by the third day, renewed vitrectomy was performed on postoperative days 4-8. RESULTS: Macular hole closure was achieved in 88 of the 112 eyes (79%). In 35 of the 88 eyes partial closure was noted on the first postoperative day. In 20 of the 24 eyes requiring renewed surgery the hole was finally closed. After a median follow-up of 144 days the macular hole was completely closed in all layers in 108 patients (96%). Mean visual acuity at final follow-up was 0.37 logMAR in group one, 0.29 logMAR in group two and 0.51 logMAR in patients whose holes closed after renewed surgery. Once closed, none of the macular holes reopened. CONCLUSIONS: The 79% initial closure rate in the present study is about 10% lower than that reported in other studies employing long-acting gas tamponades. However, renewed surgery with air tamponade achieved a closure rate of 96%. Early partial closure is sufficient for subsequent complete closure, requires no further tamponade or prolonged prone positioning, and has no negative effect on the functional results. Short-term prone positioning is sufficient for most patients.

Implications of bevacizumab on vascular endothelial growth factor and endostatin in human choroidal neovascularisation.

AIM: To evaluate the implications of intravitreal bevacizumab on proangiogenic vascular endothelial growth factor (VEGF) with regard to the endogenous angiogenesis inhibitor endostatin in human choroidal neovascularisation (CNV) secondary to age-related macular degeneration. METHODS: Retrospective review of an interventional case series of 48 patients who underwent full macular translocation surgery with removal of CNV. Twenty-five patients were treated with intravitreal bevacizumab injection 1 to 154 days prior to surgery (bevacizumab CNV). Twenty-three CNV without any kind of previous treatment were used as controls (control CNV). CNV were stained for CD34, cytokeratin18, VEGF, endostatin and E-selectin. A "predominance score of VEGF over endostatin" (PS) was defined by the difference between VEGF and endostatin staining scores. RESULTS: Bevacizumab CNV revealed a weaker VEGF expression in endothelial cells (p = 0.0245) but significantly more intense endostatin in retina pigment epithelium (RPE) (p = 0.0001) and stroma (p<0.0001). Consequently, PS was significantly lower in RPE (p = 0.02), vessels (p = 0.03) and stroma (p = 0.0004) in bevacizumab CNV. The intensity of E-selectin expression in bevacizumab CNV was comparable with that in control CNV. CONCLUSIONS: A shift within the angiogenic balance in terms of decreased VEGF predominance over endostatin is detected in human CNV treated with bevacizumab.

Specific heating power of fatty acid and phospholipid stabilized magnetic fluids in an alternating magnetic field.

Magnetic fluids (MFs) with a similar narrow size distribution of the iron oxide core were stabilized with lauric acid (MF 1), oleate (MF 2) or, after dialysis in the presence of liposomes, with phospholipid molecules (MF 3 and MF 4, respectively). The hydrodynamic sizes of the MF 1 and MF 3 were half those found for MF 2 and MF 4. The MFs were exposed to inductive heating in an alternating magnetic field at a frequency of 200 kHz and a maximum magnetic field strength of 3.8 kA m(-1). Specific absorption rates (SAR) of 294 ± 42 (MF 1), 214 ± 16 (MF 2), 297 ± 13 (MF 3) and 213  ± 6 W g(-1) Fe (MF 4) were obtained. The data for MF 2 and MF 4 were identical to those found for the commercially available ferucarbotran. The biomedical relevance of the phospholipid-coated MFs is briefly discussed.

Increased pre-SMA activation in early PD patients during simple self-initiated hand movements.

The slowness of movement, termed bradykinesia, is one of the main symptoms of Parkinson's disease (PD). This symptom may be due to the inability of PD patients to maximise the speed of internally driven movements. The mesial premotor areas and in particular the pre-supplementary motor area (pre-SMA) seem to play a crucial role in the temporal initiation of movements in humans and animals. However, this activation seems to be debatable in imaging studies of PD patients. We performed a motor paradigm with temporally self-initiated movements in nine de novo PD patients before and after initiation of dopaminergic medication. The main finding was an increased activation of the pre-SMA in de novo PD patients compared with healthy age-matched control subjects. This result indicates the contribution of the pre-SMA in the temporal initiation of self-generated movements and in the disease pathology of PD. Increased bilateral activation of the superior cerebellum, mainly on the ipsilateral side, and a decreased activation of the ipsilateral inferior cerebellum in PD patients were also present. These findings provide new insights into the activation pattern of the cerebellum in PD patients.

The effect of free polymer on the interactions and the glass transition dynamics of microgel colloids.

By studying the phase behaviour and the short range order of polystyrene microgel colloids in a good solvent we demonstrated that these particles can be considered as hard spheres or nearly hard spheres if the internal cross link density is made sufficiently high. A binary mixture of 1:50 crosslinked (1 crosslink per 50 monomers) particles with a size ratio R(small)/R(large) = 0.83 and a number ratio N(small)/N(large) = 2.7 was characterized with respect to the short range order and glass transition dynamics. We found that this mixture can be mapped onto a one-component hard sphere system with an effective polydispersity of 11%, even though for the particle interactions an inverse power potential u(r) alpha r(-35) was established. The only significant difference observed was a shift of the glass transition to a higher volume fraction of 0.595. Thus, the binary mixture was used as a non-crystallizing reference system to study the effect of free polymer on interactions and glass transition dynamics. Addition of linear polystyrene with a size ratio delta = R(g,polymer)/R(colloid) = 0.054 induced short-ranged depletion attractions between microgel particles. In the case of a glassy sample already a rather small amount of polymer leads to melting of the glass and a re-entrant glass transition is observed at high polymer content. From the difference of the line shapes of the density autocorrelation functions on approaching the different transition lines. measured over the full dynamic range, a change of the freezing mechanism from a packing-driven glass transition at low polymer content to a bonding-driven glass transition at high polymer content was deduced.

Re-entrant glass transition in a colloid-polymer mixture with depletion attractions.

Performing light scattering experiments we show that introducing short-ranged attraction to a colloid suspension of nearly hard spheres by addition of a free polymer produces new glass-transition phenomena. We observe a dramatic acceleration of the density fluctuations amounting to the melting of a colloidal glass. Upon increasing the strength of the attractions the system freezes into another nonergodic state sharing some qualitative features with gel states occurring at lower colloid packing fractions. This re-entrant glass transition is in qualitative agreement with recent theoretical predictions.

Motivation for smoking cessation: what role do doctors play?

PRINCIPLES: Cigarette smoking causes an estimated 13% of all deaths in Switzerland. Though most smokers will eventually become ex-smokers of their own volition, physicians play an important role in accelerating the process of quitting among smoking patients. Even brief advice from physicians is effective in doing so. The purpose of this study was to investigate which smokers were asked about their smoking habits, and how often, whether they received advice to quit, and how this correlates with the patient's desire to quit. METHODS: Telephone interviews were carried out with a random sample of smokers and ex-smokers from the German-speaking Swiss population (n = 993). We collected information on personal characteristics, smoking habits, and recall of physicians' advice. Data was analysed descriptively and by logistic regression. RESULTS: 88% recalled being asked by a doctor about their smoking habits. In contrast, only 34% of smoking patients recalled being advised to stop. Women, older people and those in poor subjective health were asked more frequently. Heavier smokers and those in poor subjective health were advised more frequently. Current smokers more frequently express the desire to quit if they are heavier smokers and have been advised to quit by their physician, compared with those who have not received such advice. CONCLUSIONS: Similarly to the international findings, smoking patients in Switzerland receive brief advice with insufficient frequency. Action should therefore be taken to encourage health professionals not only to question all smoking patients but to advise and motivate them to quit smoking.

Preschool children with attention-deficit/hyperactivity disorder: impairments in behavioral, social, and school functioning.

OBJECTIVE: To examine differences in home, school, and medical functioning between preschool-age children with attentiondeficit/hyperactivity disorder (ADHD) and normal control children. METHOD: A sample of 94 children (58 with ADHD, 36 normal controls) between 3 and 5 years old participated. Dependent measures included parent and teacher ratings of problem behavior and social skills, parent ratings of stress and family functioning, medical functioning data, observations of parent-child interactions and classroom behavior, and a test of preacademic skills. RESULTS: Young children with ADHD exhibited more problem behavior and were less socially skilled than their normal counterparts according to behavior ratings. Parents of children with ADHD experienced greater stress and were coping less adaptively than parents of non-ADHD children. Children with ADHD exhibited more noncompliant and inappropriate behavior than normal controls, particularly during task situations. Parents of children with ADHD were more likely to display negative behavior toward their children. Children with ADHD exhibited more negative social behavior in preschool settings and scored significantly lower on a test of preacademic skills. No significant differences in injuries or utilization of medical services were found. CONCLUSIONS: Preschool-age children with ADHD are at significant risk for behavioral, social, familial, and academic difficulties relative to their normal counterparts.

[Blood titanium levels before and after oral administration titanium dioxide]. / Titan-Blutspiegel vor und nach Belastungsversuchen mit Titandioxid.

The normal titanium levels in the blood of males between 24 and 66 years of age were found to be 11.2 micrograms/l (rsd 4.1). After oral administration of titanium dioxide containing capsules or as powder (anatas) it could be observed that the material can be absorbed from the gastro-intestinal tract. If two titanium dioxide qualities, having different mean particle sizes (0.16 micron and 0.38 micron), are administered orally, the latter shows less absorption, most likely due to agglomeration phenomena. The blood concentration/time correlation shows the type of curves which are characteristic for a persorption mechanism of absorption and reveal a high individual fluctuation. An increase of the administered dose by twice the amount shows only a tendentious response in the corresponding blood levels. The method of analysis was ICP-AES. A pretreatment of the samples in order to eliminate the organic matrix is necessary.

The effect of combined oestrogen and progesterone replacement on the renal responses to oxytocin and vasopressin in ovariectomized rats.

OBJECTIVE: Renal responsiveness to the neurohypophyseal hormones, oxytocin and vasopressin, has been shown in the rat to vary during pregnancy and lactation. A study was performed to determine whether ovarian steroids could contribute to the observed changes. DESIGN: Using a previously validated method, fluid excretion during infusion of oxytocin or vasopressin was monitored in ovariectomized animals with and without chronic administration of oestrogen and progesterone. METHODS: After 14 days treatment with vehicle or 12.5 mg hydroxyprogesterone caproate and 0.25 mg oestradiol valerate injected every 3 days, rats were infused with 0.077 mol/l NaCl for an equilibration period of approximately 2.5h. Timed urine collections for the determination of volume and electrolytes were then made during a control period of at least 45 min and for 60 min while the infusate was supplemented with vasopressin (40 fmol/min) or oxytocin (50 fmol/min). Further observations were made for a final 90 min of hypotonic saline infusion. In control infusions saline alone was given. RESULTS: Treatment with ovarian steroids did not affect the volume of urine excreted during hormone infusion. Electrolyte excretion, however, was affected with lower concentrations of sodium and chloride on oxytocin infusion being seen in the steroid-treated animals. During vasopressin infusion, peak electrolyte concentrations were also achieved later in this group of animals. CONCLUSION: The increased circulating concentrations of oestrogen and progesterone seen during pregnancy could contribute to variations in the natriuretic response to neurohypophyseal hormones observed in the rat.

Adolescent suicide prevention: acceptability of school-based programs among secondary school principals.

High school principals' acceptability ratings of three school-based programs for the prevention of adolescent suicide were examined. From a random sample of members from the 1994-1995 membership directory of the National Association of Secondary School Principals (NASSP), a total of 185 (40%) respondents completed the Suicide Prevention Program Rating Profile (SPPRP), a measure designed to evaluate the acceptability of suicide prevention programs, after reading a description of a particular prevention program. Programs evaluated for their acceptability included (1) curriculum-based programs presented to students, (2) in-service presentations to school staff, and (3) student self-report screening measures. The results indicated that the curriculum-based and staff in-service programs were significantly more acceptable to principals than was the schoolwide student screening program. No significant differences between the acceptability of curriculum-based and inservice programs were found. Limitations of the study and implications for practice and research are discussed.

Economic analysis of an outbreak of avian influenza, 1997-1998.

OBJECTIVE: To determine economic losses associated with an outbreak of avian influenza in flocks in Pennsylvania during 1997 and 1998. SAMPLE POPULATION: 5 premises containing avian influenza-infected layer, pullet, and turkey flocks. PROCEDURE: Losses incurred before depopulation, those incurred at the time of depopulation, and those that were attributable to depopulation (unrealized loss of income) were evaluated. Results were extrapolated to provide values for all infected flocks. RESULTS: Extrapolating the costs determined on the basis of age and number of birds from the 5 sample flocks to all other flocks infected with nonpathogenic avian influenza H7N2 yielded an estimated total cost to the Pennsylvania poultry industry of $3.5 million. CLINICAL IMPLICATIONS: The H7N2 virus is not highly pathogenic. If the pathogenicity of the virus does not change, then the poultry industry and state and federal governments will not have severe economic losses for the 1997-1998 outbreak similar to those for the 1983-1984 avian influenza outbreak in Pennsylvania. To decrease the potential for financial losses that could result from future outbreaks of avian influenza, it is essential that the commercial industry and livebird market system be separated via increased use of biosecurity measures.

Tight binding of bulky fluorescent derivatives of adenosine to the low affinity E2ATP site leads to inhibition of Na+/K+-ATPase. Analysis of structural requirements of fluorescent ATP derivatives with a Koshland-Némethy-Filmer model of two interacting ATP sites.

A Koshland-Némethy-Filmer model of two cooperating ATP sites has previously been shown to explain the kinetics of inhibition of Na+/K+-ATPase (EC 3.6.1.37) by dansylated ATP (Thoenges, D., and Schoner, W. (1997) J. Biol. Chem. 272, 16315-16321). The present work demonstrates that this model adequately describes all types of interactions and kinetics of a number of ATP analogs that differ in their cooperativity of the high and low affinity ATP binding sites of the enzyme. 2',3'-O(2,4,6-trinitrophenyl)ATP binds in a negative cooperative way to the E1ATP site (Kd = 0.7 microM) and to the E2ATP site (Kd = 210 microM), but 3'(2')-O-methylanthraniloyl-ATP in a positive cooperative way with a lower affinity to the E1ATP binding site (Kd = 200 microM) than to the E2ATP binding site (Kd = 80 microM). 3'(2')-O(5-Fluor-2,4-dinitrophenyl)-ATP, however, binds in a noncooperative way, with equal affinities to both ATP binding sites (Kd = 10 microM). In a research for the structural parameters determining ATP site specificity and cooperativity, we became aware that structural flexibility of ribose is necessary for catalysis. Moreover, puckering of the ring atoms in the ribose is essential for the interaction between ATP sites in Na+/K+-ATPase. A number of derivatives of 2'(3')-O-adenosine with bulky fluorescent substitutes bind with high affinity to the E2ATP site and inhibit Na+/K+-ATPase activity. Evidently, an increased number of interactions of such a bulky adenosine with the enzyme protein tightens binding to the E2ATP site.

Suspected malignant hyperthermia in a 13-month-old: today's "typical" episode--a case report.

A case of suspected malignant hyperthermia in a 13-month-old female, to whom succinylcholine was not administered, is presented. The patient presented for a repair of the right radial nerve under general anesthesia. Induction was accomplished with halothane, nitrous oxide, and oxygen. Tracheal intubation was facilitated with intravenous vecuronium. Controlled ventilation was initiated, and anesthesia was maintained with isoflurane, nitrous oxide, oxygen, morphine sulfate, and vecuronium. At the conclusion of the surgical procedure, an abrupt increase in ETCO2, an elevation in body temperature, and a mixed acidosis was observed. Resolution of symptoms followed the administration of dantrolene sodium. The patient underwent an uneventful postoperative recovery and was discharged home. It was felt that the patient was too young to undergo a muscle biopsy for a caffeine-halothane stimulation test.

Effects of reinforcer quality on behavioral momentum: coordinated applied and basic research.

The high-probability (high-p) instructional sequence has been an effective treatment for noncompliance. However, treatment failures have also been reported. We hypothesized that the efficacy of the high-p treatment may be improved by using higher quality reinforcers for compliance to high-p instructions. The resistance of compliance to change was tested by varying reinforcer quality in two applied studies and a basic laboratory experiment. Experiment 1 tested the hypothesis that an increase in reinforcer quality for high-p compliance will increase the effectiveness of the high-p treatment when it fails to increase compliance. Experiment 2 assessed the effects of reinforcer quality on resistance of compliance to change by presenting successive low-p requests following the high-p treatment. A basic laboratory study (Experiment 3) was conducted to further isolate the relation between reinforcer quality and behavioral momentum. Two different liquid reinforcers (sucrose and citric acid solutions) were presented in a two-component multiple variable-interval variable-interval schedule followed by a single extinction test session. Results of all three experiments showed a generally consistent relationship between reinforcer quality and behavioral momentum.