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Many structural properties of conventional passive materials are known to arise from the symmetries of their microscopic constituents. By contrast, it is largely unclear how the interplay between particle shape and self-propulsion controls the meso- and macroscale behavior of active matter. Here we use large-scale simulations of homo- and heterogeneous self-propelled particle systems to identify generic effects of broken particle-shape symmetry on collective motion. We find that even small violations of fore-aft symmetry lead to fundamentally different collective behaviors, which may facilitate demixing of differently shaped species as well as the spontaneous formation of stable microrotors. These results suggest that variation of particle shape yields robust physical mechanisms to control self-assembly of active matter, with possibly profound implications for biology and materials design.

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Individuals with autism spectrum disorder (ASD) show impairments in processing coherent motion which have been proposed to be linked to a general deficit in the dorsal visual pathway. However, few studies have investigated the neural mechanisms underlying coherent motion processing in ASD. Thus, the aim of this study was to further test the hypothesis of a dorsal pathway deficit in ASD using visual evoked potentials (VEPs). 16 children and adolescents with ASD and 12 typically developing controls were examined with VEPs elicited by a random dot kinematogram. After an initial experimental sequence, where subjects were presented randomly moving dots, a fraction of the dots moved coherently (dependent on the level of coherence, 20%, 40%, or 60% of the dots) to the left or right side. Subjects were asked to detect the direction of coherent motion via button press. On the behavioural level, no significant group differences emerged. On the neural level, coherently moving dots elicited a N200 followed by a late positive potential (P400). ASD subjects exhibited a reduced N200 amplitude compared to controls. Moreover, in the ASD group, a trend for a negative relationship between N200 amplitude and a measure of autistic pathology was revealed. The present study provides strong support of a dorsal stream deficiency in the disorder and renders alternative explanations for impaired coherent motion processing in ASD less likely. Together with findings from related research fields, our data indicate that deviances in the N200 during coherent motion perception might be fundamental to ASD.

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We report the case of a 39 years old patient with sudden onset of abdominal distension and icterus. Occlusion of the liver veins discovered by doppler ultrasound caused the portal hypertension and liver disease. Given the erythrocytosis the detection of JAK 2-mutation proved polycythemia vera as underlying disease for the Budd Chiari syndrome. The implantation of a TIPS wasn't successful because of an early thrombotic occlusion. Therefore a surgical mesocaval shunt was done. At the moment the patient is therapied with oral anticoagulation and hydroxycarbamide and is fully capable of work again.

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We calculate the escape rates of different dynamical processes for the case of a one-dimensional symmetric double-well potential. In particular, we compare the escape rates of a Smoluchowski process, i.e., a corresponding overdamped Brownian motion dynamics in a metastable potential landscape, with the escape rates obtained for a biologically motivated model known as the Fisher-Eigen process. The main difference between the two models is that the dynamics of the Smoluchowski process is determined by local quantities, whereas the Fisher-Eigen process is based on a global coupling (nonlocal interaction). If considered in the context of numerical optimization algorithms, both processes can be interpreted as archetypes of physically or biologically inspired evolutionary strategies. In this sense, the results discussed in this work are utile in order to evaluate the efficiency of such strategies with regard to the problem of surmounting various barriers. We find that a combination of both scenarios, starting with the Fisher-Eigen strategy, provides a most effective evolutionary strategy.

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RATIONALE AND OBJECTIVES: The authors evaluated selective perfusion of the coronary arteries in the isolated rat heart as a model for studying contrast medium-induced cardiac effects and compared the effects of iodixanol, iotrolan, and ioxaglate with this model. MATERIALS AND METHODS: Isolated, spontaneously beating rat hearts were used. Control hearts were perfused in the Langendorff or the selective perfusion mode receiving Krebs Henseleit buffer. Contrast media were injected selectively into the left coronary artery. Left ventricular pressure and electrocardiographic parameters were monitored continuously throughout the experiments. RESULTS: The stability of the selective perfusion preparation was similar to that of the conventional Langendorff preparation. Ioxaglate (0.3 g iodine per kilogram body weight) significantly (P < .05) depressed left ventricular contractility and decreased (P < .05) left ventricular pressure. Iodixanol and iotrolan had minor cardiac effects. CONCLUSION: Selective coronary artery perfusion seems to be a suitable model for studying direct cardiac effects of contrast media. The nonionic dimers, iodixanol and iotrolan, induce only minor changes in cardiac function.

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RATIONALE AND OBJECTIVE: The study was designed to compare acute and direct cardiotoxicity of gadopentetate dimeglumine, gadoteridol injection, and gadodiamide injection. METHODS: Two consecutive injections of contrast material (0.3 to 1.5 mmol/kg body weight) were given to spontaneously beating, isolated rat hearts. Cardiac function was assessed by measuring left ventricular developed pressure (LVDP), perfusion pressure, and electrocardiographic (ECG) parameters. RESULTS: Gadopentetate dimeglumine decreased LVDP, and its first derivatives (+/- dP/dt max) substantially more than gadodiamide injection. Gadoteridol increased these variables. PR and RT intervals lengthened after 1.5 mmol/kg gadopentetate dimeglumine and gadoteridol injection. Bradycardia and ventricular tachyarrhythmias were seen after injection of 1.5 mmol/kg gadopentetate dimeglumine. Except for isolated ventricular premature beats, gadodiamide injection and gadoteridol injection did not provoke any serious arrhythmia. CONCLUSION: Gadopentatate dimeglumine induced negative inotropy and more pronounced ECG disturbances. Gadoteridol injection and gadodiamide injection induced only small changes in left ventricular inotropy and minor electrophysiologic effects.

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PURPOSE: To identify psychological correlates of adolescent depression. METHODS: The subjects (N = 156) represented a convenience sample of adolescents who were attending public high schools in four Midwestern rural communities. Instruments used were: The Center for Epidemiologic Studies Depression Scale of Children, Loneliness Inventory-Short Form, Rosenberg Self-Esteem Scale, Family Strengths Inventory, and Parent-Adolescent Communication Inventory. FINDINGS: Higher levels of depression were associated with loneliness (r = .646, p < or = .001) and low self-esteem (r = .596, p < or = .001). Depression was negatively related to family strengths (r = -.293, p < or = .001). Older adolescents were more depressed than younger adolescents (r = .332, p < or = .001). A stepwise regression identified three pertinent factors associated with depression: loneliness, self-esteems, and age. CONCLUSION: Implications for nursing practice include interventions that minimize the exacerbating factors associated with depression in the adolescent population.

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This study was designed to compare the cardiac electrophysiology and mechanical effects of iodixanol to those of iotrolan, iopromide, ioxaglate and diatrizoate. Two consecutive injections of contrast media (CM) (0.3 g I/kg and 0.9 g I/kg b.w.) were given to spontaneously beating, Langendorff-perfused rat hearts. CM were given as a single, short-lasting bolus injection (i.e. over 2 and 5 s). Changes in aortic pressure, left ventricular pressures and ECG were continuously recorded during constant volume perfusion. The nonionic CM had less pronounced effects on aortic pressure than had the ionic media. The peak rate of isovolumetric contraction (LV dP/dt(max)) was slightly decreased by iodixanol and iotrolan, slightly more decreased by iopromide and markedly decreased by ioxaglate and diatrizoate. Similarly, the peak rate of pressure decline (LV dP/dt (min)) was only slightly decreased by iodixanol and iotrolan. Also, the 2 nonionic dimers had the smallest effects on the left ventricular end diastolic pressure (LVEDP) and heart rate. Ioxaglate lengthened the PQ-interval, but less so than diatrizoate. THe QT-interval was only slightly lengthened by iodixanol and iotrolan, as compared to the lenghthening caused by iopromide, ioxaglate and diatrizoate. Single ventricular extrasystoles were seen in all groups. Extrasystoles up to 3 coupled beats were registered after ioxaglate and diatrizoate. No episodes of ventricular fibrillation occurred with any CM. In conclusion, the nonionic dimers, and in particular iodixanol, induce only minor changes in cardiac function, whereas the ionic dimer ioxaglate and the ionic monomer diatrizoate induce pronounced effects.

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Absorption and excretion of iodixanol 320 mg I/ml were investigated in rats after intragastric administration of 2.5 g I/kg b.w. Animals were observed for up to 96 hours after treatment, and blood, urine and feces taken at several time-points throughout the experiment. Concentrations of iodixanol in serum and urine were measured by means of reversed-phase high-performance liquid chromatography. Fecal concentrations of iodixanol, based on iodine measurements, were determined by X-ray fluorescence spectrometry. Serial radiographs were obtained and histopathological examination was performed on selected tissues. The results indicate that less than 1% of the intragastric dose of iodixanol is absorbed from the intestine into the blood stream. No adverse clinical signs were observed, and there were no treatment-related histomorphological findings.

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To compare the impact of using Minnesota antilymphoblast globulin (MALG) versus the monoclonal antibody, OKT3, on the development of symptomatic cytomegalovirus (CMV) infection, we reviewed a cohort of 130 cadaveric renal transplant recipients enrolled in a prospective comparison of MALG versus OKT3 for rejection prophylaxis. Among the 112 patients at risk for CMV, prophylactic MALG was associated with an increased risk of symptomatic infection (relative hazard [rh] = 3.31; 95% confidence interval CI], 1.50 to 7.30; P = 0.003). Transplantation of kidneys from CMV-seropositive donors into CMV-seronegative recipients (rh = 5.22; 95% CI, 2.34 to 11.63; P = 0.00004), first transplantation (rh = 4.76; 95% CI, 1.06 to 21.3; P = 0.039), and acute rejection therapy (rh = 2.03; 95% CI, 0.98 to 4.21; P = 0.055) were also associated with an increased risk. Prophylactic MALG followed by treatment with any agent for acute rejection was strongly correlated with symptomatic CMV infection (rh = 4.46; 95% CI, 3.71 to 5.21; P = 0.00006). Symptomatic CMV infection was not only more frequent, but more severe in recipients of prophylactic MALG, and more MALG recipients were treated with ganciclovir. There was no difference in rejection rate for the two rejection prophylaxis regimens (P = 0.625). Prophylactic OKT3 results in less risk of symptomatic CMV infection than prophylactic MALG in cadaveric renal transplant recipients who are seropositive for CMV or whose donors are seropositive for CMV.(ABSTRACT TRUNCATED AT 250 WORDS)

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Demographic information, risk factors, therapy, and outcome for all patients who had candidemia at Barnes Hospital, St. Louis, between 1 September 1988 and 1 September 1989 were retrospectively reviewed. One hundred six candidemic patients were identified, representing 0.5% of all medical and surgical discharges and 0.33% of total patient discharges. These percentages represent a 20-fold increase in the incidence of candidemia at our hospital in comparison with that during 1976-1979. Candida albicans was the most frequently isolated species (63%), followed by Candida tropicalis (17%), Candida glabrata (13%), Candida parapsilosis (6.5%), and Candida krusei (0.9%). Overall mortality was 57%, and 14 (23%) of 60 deaths occurred within 48 hours of the detection of candidemia. Mortality was associated with higher APACHE II scores (25 for nonsurvivors vs. 16 for survivors; P = .0001), the presence of a rapidly fatal underlying illness (P = .0009), and sustained positivity of blood cultures (P = .02). In cases of sustained candidemia, the isolation of non-albicans Candida species also correlated with increased mortality (8 of 8 vs. 10 of 21; P = .005). Thirty candidemic patients (28%) did not receive any antifungal therapy, and 19 (63%) of these untreated patients died. Eleven untreated patients (37%) survived without sequelae. There has been a marked increase in the incidence of candidemia in our institution that is associated with a high overall mortality. Candidemia lasting less than 24 hours was associated with a lower mortality than was that of longer duration. Severity of illness and duration of candidemia should be used as stratifying factors in prospective studies to determine optimum therapy.

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In summary, families in the ICU have had both a positive and a negative effect on staff. On the positive side there is an increased opportunity for staff to get feedback and appreciation. Goals can be realistically refocussed to help the family when a patient can no longer be helped, thus broadening the role of the staff. This also applies to the nurse advocacy role being enhanced by the increased patient data provided by the family. The opportunity to personalize the patient, to get to know him, is provided by the family's presence. And when a patient dies in the unit a family's grieving can help the staff with closure around its own grief. Families who express unrealistic demands of the ICU staff can be experienced as a stress. Staff who feel unsure of themselves or criticized by families have found the presence of families difficult. Staff who prefer to remain detached from patients also are uncomfortable with increased family presence. Feelings of rivalry with those nurses seen as "super nurses" has been a source of stress for a few in the unit. Discussions of how the staff feels about families and how certain families make the staff members feel about themselves have helped to maintain an objectivity on the part of the staff. Identifying the stress and providing support and understanding for staff have reduced the numbers of exacerbations and provided increased opportunities for staff and family to work together toward their common goal--the well-being of the patient.

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To investigate mesenteric hemodynamics in early perinephritic hypertension, we measured blood flows and intravascular pressures in innvervated, collateral-free, naturally perfused loops of ileum in 50 male mongrel dogs anesthetized with sodium pentobarbital. In addition, we studied venous pressure-volume relationships in temporarily occluded segments of mesenteric veins in vivo and in excised segments of mesenteric veins in vitro. In 10 dogs (group H-1), one kidney was wrapped in silk 11 days before study; in 15 other dogs (group H-2), one kidney was wrapped 4 weeks before study and the other was removed 2 weeks before study. Twenty-five additional dogs were prepared as normotensive controls: in 10 one kidney was sham-wrapped (group C-1), and in 15 one kidney was sham-wrapped and the other was removed (group C-2). A significant rise in mean arterial blood pressure occurred in groups H-1 and H-2. Compared to controls, (1) ileal blood flow in the hypertensive dogs (H-1 plus H-2) was increased by 17% (P smaller than 0.05), (2) calculated ileal vascular resistances (total and segmental) were unchanged (P smaller than 0.05), and (3) in vivo and in vitro mesenteric vein pressure-volume curves of H-2 (but not of H-1) hypertensive dogs were shifted in the direction of the pressure axis (P smaller than 0.05). These data suggest that in the early stages of perinephritic hypertension in dogs (1) ileal blood flow is increased. (2) ileal vascular resistance is not elevated, and (3) mesenteric venous compliance is reduced. Analysis of the venous pressure-volume curves suggests that the decreased venous compliance is attributable to factors other than smooth muscle contraction.

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