Total Time Course Research Articles

High species homology potentiates quantitative inflammation profiling in zebrafish using immunofluorescence

Due to substantial homology between the human and zebrafish genome and a high level of conservation of the innate immune system across species, zebrafish larvae have become an invaluable research tool for studying inflammation and modelling inflammatory disease. However, further microscopy techniques need to be developed for better profiling of inflammation and in particular, integrated cytokine responses to different stimuli - approaches are currently largely limited to assessment of changes in cytokine gene transcription and in vivo visualisation using transgenics, which is limited in terms of the number of cytokines that may be assessed at once. In this study, after confirming substantial homology of human vs zebrafish cytokine amino acid sequences, immunofluorescence staining using antibodies directed at human cytokines was performed. Inflammatory cytokine signalling responses to experimental tailfin transection was assessed over 24 h (1 hpi (hours post injury), 2 hpi, 4 hpi, 24 hpi) in zebrafish larvae, with experimental end point at 120 h post fertilization (hpf). When immunofluorescence results were compared to responses observed in rodent and human literature, it is clear that the cytokines follow a similar response, albeit with a condensed total time course. Notably, tumor necrosis factor-α and monocyte chemoattractant protein-1 increased and remained elevated over the 24-h period. In contrast, interleukin-1β and interleukin-6 peaked at 4 hpi and 2 hpi respectively but had both returned to baseline levels by 24 hpi. Macrophage migration inhibitory factor was lowest at 1 hpi, potentially encouraging macrophage movement into the site of injury, followed by a sharp increase. This protocol provides valuable insight into inflammation over a time course and more so, provides an affordable and accessible method to comprehensively assess inflammation in zebrafish disease models.

Annotation of Novel Dynamic UTRs as Functional Targets of miRNAs During Cardiac Development

Small noncoding microRNAs (miRNAs) play essential roles in post-transcriptional gene regulation in development and disease, predominantly through interactions with mRNA untranslated regions (UTRs). However, the dynamic and tissue specific expression of miRNAs and target UTRs throughout development is poorly characterized. In order to understand the RNA regulatory events that drive cardiac morphogenesis, we captured a simultaneous small RNA and total RNA-seq time course in zebrafish hearts. We extracted de novo transcriptome annotation of dynamically changing UTRs, revealing over ten thousand significantly altered transcripts, with novel 5’ and 3’UTRs for approximately half of all protein coding genes, and predicted regulatory miRNA/UTR interactions during development. In addition to miRNA and mRNA transcriptome resources for studies of RNA regulatory events in cardiac development and disease, this study provides a robust bioinformatic pipeline that should facilitate discovery of posttranscriptional regulatory networks in other developmental systems.

TEACHING MUST GO ON: flexibility and advantages of peer assisted learning during the COVID-19 pandemic for undergraduate medical ultrasound education - perspective from the "sonoBYstudents" ultrasound group.

Background: Facing the global COVID-19 pandemic University teaching has been digitalized and German medical faculties took great effort to offer curricular contents online as they agreed that semesters during pandemic should not be suspended. Skill training is an essential part of medical education and cannot be fully digitalized nor should it be omitted. The pandemic demonstrates that skills like ultrasound are essential when treating critical ill patients. Medical faculties use peer assisted learning (PAL) concepts to teach skills, like ultrasound through specially trained student tutors.Aim: Here, we would like to share our experiences and elaborate how ultrasound teaching can be safely performed during the pandemic with an emphasis on adjustment of an existing PAL teaching concept.Method: At the hospital of Saarland University, we implemented a PAL teaching concept for abdominal, including emergency, ultrasound, and echocardiography, called “sonoBYstudents” to teach sonography to undergraduate medical students. Students are generally taught in small groups of 5 people in 90min sessions over a time of 8 weeks with an objective structured clinical exam (OSCE) at the end of the course program. Each semester nearly 50 students are taught in abdominal and emergency ultrasound and 30 students in echocardiography. Over five years, more than 600 students have been taught with at least 30 students being trained as student tutors. Given the pandemic, course size, course interval and total course time and total course time were adapted to the hygienic precautions. Results: 45 and 30 students were taught in abdominal ultrasound and echocardiography respectively achieving their learning goals measured via OSCE at the end of the courses. OSCE results were the same when compared to previous semesters. Conclusion: PAL as a teaching concept lives out of sustained educational strategies like practical and didactical trainings and an ongoing recruitment of new student tutors. Suspending PAL and its skill teaching would require starting from the beginning which is a time and cost consuming process. With sonoBYstudents we were able to demonstrate that an existing PAL concept can, with some effort, be adjusted to changing teaching circumstances. Apart from this ultrasound is a non-omittable part of medical skill training with easily appliable hygienic precautions during teaching sessions.

Characterizing C5 Inhibition with the SMART-Ig Anti-hC5 Antibody Crovalimab in PNH Patients Using Free Available Paratopes

Characterizing C5 Inhibition with the SMART-Ig Anti-hC5 Antibody Crovalimab in PNH Patients Using Free Available Paratopes

Combined Deep Brain Stimulation of Subthalamic Nucleus and Ventral Intermediate Thalamic Nucleus in Tremor-Dominant Parkinson’s Disease Using a Parietal Approach

Despite its efficacy in tremor-suppression, the ventral intermediate thalamic (VIM) nucleus has largely been neglected in deep brain stimulation (DBS) for tremor-dominant Parkinson's disease (tdPD). The employment of a parietal approach, however, allows stimulation of VIM and subthalamic nucleus (STN) using one trajectory only and thus constitutes a promising alternative to existing strategies. In the present study, we investigate safety and efficacy of combined lead implantation and stimulation of STN and VIM using a parietal approach. Retrospective analysis of five patients with tdPD was performed who underwent DBS using a parietal approach. Changes in symptom severity, disease-specific health-related quality of life and l-dopa equivalent doses (LED) were evaluated over a total time course of 12 months. DBS within both targets yielded significant improvement of parkinsonian symptoms (median: 40.0%, p = 0.04) in the first 6 months of continuous stimulation and remained stable thereafter (median improvement at 12 months: 43.2%, p = 0.07). Sustained improvement of tremor (median at 6 months: 100.0%, p = 0.04; median at 12 months 83.3%, p = 0.04) and quality of life scores (median at 6 months: 29.8%, p = 0.04; median at 12 months: 32.6%, p = 0.04) was noted throughout the follow-up period. No significant change of LEDs was observed by the end of follow-up (median decrease: 2.2%, p = 0.89). Simultaneous DBS of VIM and STN using one trajectory is safe, yielding good control of parkinsonian tremors. Further studies, however, are necessary to determine whether a parietal trajectory affords better control over tremor symptoms than established strategies and hence justifies the potential risks associated with the alternative approach.

Combinations of Symptoms in Emergency Presentations: Prevalence and Outcome.

The predictive power of certain symptoms, such as dyspnoea, is well known. However, research is limited to the investigation of single chief complaints. This is in contrast to patients in the emergency department (ED) presenting usually more than one symptom. We aimed to identify the most common combinations of symptoms and to report their related outcomes: hospitalisation, admission to intensive care units, and mortality. This is a secondary analysis of a consecutive sample of all patients presenting to the ED of the University Hospital Basel over a total time course of 6 weeks. The presence of 35 predefined symptoms was systematically assessed upon presentation. A total of 3960 emergency patients (median age 51, 51.7% male) were included. Over 130 combinations of two, 80 combinations of three, and 10 combinations of four symptoms occurred 42 times or more during a total inclusion period of 42 days. Two combinations of two symptoms were predictive for in-hospital mortality: weakness and fatigue (Odds ratio (OR) = 2.45), and weakness and headache (OR = 3.01). Combinations of symptoms were frequent. Nonspecific complaints (NSCs), such as weakness and fatigue, are among the most frequently reported combinations of symptoms, and are associated with adverse outcomes. Systematically assessing symptoms may add valuable information for prognosis and may therefore influence triage, clinical work-up, and disposition.

Multiple Myeloma Vaccination Sequential Immune Response Pilot Study

BackgroundMultiple myeloma (MM) is a cancer of the immune system. Infection is a major cause of morbidity and mortality in MM. Vaccinations (vax) are recommended in MM, but clinical efficacy endpoints have not been demonstrated and surrogate markers of efficacy have limited data. This pilot study evaluated sequential immunologic markers after standard vax for pneumococcal pneumonia (PV) and influenza (FV).MethodsMM patients and non-MM control (Ctrl) participants signed informed consent to this IRB approved study. The MM patients were not selected for treatment or disease status. Vax was standard PV (PCV13 or PPV23) and/or FV (IIV4) with research laboratory testing at baseline and at 2, 4, 12, 24 weeks after vax. If PV, then PCV13 preferred followed by PPV23 suggested at >= 26 weeks. IgG antibodies (Ab) to influenza and pneumococcal antigens were detected by ELISA. Measurement of Ab to influenza was performed as previously described (Oaks et al. 2013OncoImmunology) and used Flulaval Quadrivalent 2015/2016 form (GlaxoSmithKline) as the coating antigen. Anti-pneumococcal IgG levels were determined with The Binding Site VaccZymeAnti-PCP IgG EIA Kit (#MK012-U) according to the manufacturer’s instructions.ResultsTen MM (5 M, 5 F) and 9 Ctrl (4 M, 5 F) were enrolled. MM median age was 69.8y (range: 59-78) and Ctrl was 63.5y (range: 56-73). Over the total time course 5/10 MM and 4/9 Ctrl had no missing samples. Vax included: 5 (2 MM, 3 Ctrl) FV only; 10 (6 MM, 4 Ctrl) PV (8 PCV13, 2 PPV23) only; and 4 (2 MM, 2 Ctrl) both FV and PV (3 PCV13, 1 PPV23). Tetanus Ab response was unchanged, which served as a negative control. FV results included 2/4 MM showed at least a doubling of anti-flu titer, although the other 2 showed no measurable response. All 5/5 Ctrl had at least a 2-fold increase in anti-flu titers at some point. PV humoral response varied considerably for both MM and Ctrl. All 4 Ctrl responded with at least a 2-fold increase in Ab titer, only 2 Ctrl had a sustained increase in titer at the closing visit. Six of 10 MM had at least a 2-fold Ab increase at some point during the course of the study. Only 2 MM patients showed a sustained increase of anti-PV Ab. Response rate differences were not statistically significant and there was no relationship between responsiveness to FV or PV and initial serum IgG concentration at entry into the study (data not shown).DiscussionStudy limitations include small sample size, sample dropouts, and heterogeneous population. We are unaware of prior MM vax immunology response time courses. This may be because of the difficulties including PV studies with PCV13->PPV23 recommendations and the potential long follow up. FV response may be more amenable to short term follow up. In 2013 Hahn and colleagues showed proof of principle with "Boost vax improves influenza humoral immune response in MM" (ow.ly/sEBEO), but without a time course or clinical outcomes data. The 2015Branagan et al. (http://ow.ly/W4tLS) pilot study showed a 2 dose FV strategy had lower flu infections compared to historical controls. Karlsson et al. (http://ow.ly/YUumy) showed that Ab response does not correlate with functional assays. We found no relationship with total IgG level. This is consistent with Beers et al. findings that IgG isotypes may be of more importance than the total IgG level. (http://ow.ly/Z5g2A)ConclusionWe found that FV and PV Ab response was low and not sustained in most MM patients. Infection in MM remains an important concern. Future vax studies should address the following: 1) Homogeneous population - eg therapy trial or autologous stem cell transplant with a standardized re-vax and sequential testing, 2) validate relevant immunologic surrogates - eg Ab response twice baseline, 4) fresh assay vs frozen (batched), 5) correlation of metric with functional outcomes such as hospitalization, cost, and death, 6) and epidemiologic data may complement translational approaches.FundingFunding was provided by a Vince Lombardi Cancer Foundation Aurora Cancer Research Award.Responses to FV [Display omitted] DisclosuresThompson:Celgene: Membership on an entity's Board of Directors or advisory committees, Other: MDS/AML Registry; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees; AIM Specialty Health: Membership on an entity's Board of Directors or advisory committees; VIA Oncology: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees, Other: Multiple Myeloma International Registry; Doximity: Equity Ownership, Membership on an entity's Board of Directors or advisory committees.

Biofunctional porous anodized titanium implants for enhanced bone regeneration

Efficient osseointegration is a key factor in dental implants to reduce the total time-course of therapy. Titanium implants with anodized surface gained much interest for their enhanced osseointegration. Anodized implant combined with bioactive drugs is an ideal candidate for enhance bone regeneration. Previously delivery of drugs from the metal implants has been attempted by utilizing a polymeric dip-coating method. However, the entire surface coating with polymer can diminish the advantageous surface roughness of anodized implants and cause contact inhibition between bone and implant surface. In this study, fibroblast growth factor-2 (FGF-2) loaded poly(lactide-co-glycolide) nanoparticles were partially coated on anodized Ti discs by an electrospray deposition. Nanoparticle coated anodized discs maintained their native porous structure and provided a sustained release of FGF-2 for more than 2 weeks with 40% initial burst. In vitro study confirmed the influence of polymeric nanoparticles and the release of growth factors from the Ti disc. Nanoparticle-coated groups significantly enhanced cell spreading and differentiation. For in vivo evaluation, the anodized titanium implants were applied to rabbit tibia model. The osseointegration was estimated by bone to implant contact of best three consecutive threads at the border of the implant. The mean osteointegration value of FGF-2 releasing implant groups (70.1%) was significantly higher than that of untreated implants (47.1%). We believe that the electrospray deposition technique is a particularly attractive approach for the coating of medical devices with porous surface to maintain their surface topography while allowing a sustained delivery of growth factors for bone regeneration. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3639-3648, 2014.

Effects of long-term head-down-tilt bed rest and different training regimes on the coagulation system of healthy men

Immobility plus preexisting chronic disease or acute trauma can activate the coagulation system, thus increasing the risk for thromboembolic events. The effects of long-term bed-rest immobility and microgravity on the coagulation system of healthy persons (e.g., during crewed Mars missions) have not yet been studied. The main objective of the second Berlin BedRest Study (BBR2-2) “Coagulation Part” was to investigate adaptations of the hemostatic system during long-term bed rest (60 days) under simulated microgravity (6° head-down-tilt [6°HDT]) and after mobilization in three different volunteer groups (randomly assigned to CTR= inactive control group; RE= resistive exercise only group; and RVE= resistive exercise with whole-body vibration group). In 24 males (aged 21–45 years), before, during, and after long-term bed rest, key parameters of coagulation were measured from venous blood samples: D-dimer (DD), thrombin–antithrombin III complex (TAT), and prothrombin fragment F1 + 2 (PT-F1 + 2). Additionally, modified rotational thrombelastometry (ROTEM®) analysis was performed. Times of exploratory analyses were as follows: baseline data collection 2 days before bed rest (BDC-2); eight different days of 6°HDT bed rest (HDT1–HDT60), and two different days after reambulation (R + 3 and R + 6). We found significant changes in DD, TAT, and PT-F1 + 2 over the total time course, but no consistent effect of physical interventions (RE, RVE) on these parameters. Notably, no parameter reached levels indicative of intravascular thrombin formation. All ROTEM® parameters remained within the normal range and no pathological traces were found. Sixty days of 6°HDT bed rest are not associated with pronounced activation of the coagulation system indicative of intravascular thrombus formation in healthy volunteers independent of the training type during the bed rest.

Brain glucose transporter (Glut3) haploinsufficiency does not impair mouse brain glucose uptake

Mouse brain expresses three principal glucose transporters. Glut1 is an endothelial marker and is the principal glucose transporter of the blood-brain barrier. Glut3 and Glut6 are expressed in glial cells and neural cells. A mouse line with a null allele for Glut3 has been developed. The Glut3−/− genotype is intrauterine lethal by 7days post-coitis, but the heterozygous (Glut3+/−) littermate survives, exhibiting rapid post-natal weight gain, but no seizures or other behavioral aberrations. At 12weeks of age, brain uptake of tail vein-injected 3H-2-deoxy glucose in Glut3+/− mice was not different from Glut3+/+ littermates, despite 50% less Glut3 protein expression in the brain. The brain uptake of injected 18F-2-fluoro-2-deoxy glucose was similarly not different from Glut3+/− littermates in the total amount, time course, or brain imaging in the Glut3+/− mice. Glut1 and Glut6 protein expressions evaluated by immunoblots were not affected by the diminished Glut3 expression in the Glut3+/− mice. We conclude that a 50% decrease in Glut3 is not limiting for the uptake of glucose into the mouse brain, since Glut3 haploinsufficiency does not impair brain glucose uptake or utilization.

Effect of propofol on twitch diaphragmatic pressure evoked by cervical magnetic stimulation in patients

BackgroundSeveral studies have demonstrated the inhibitory effect of propofol on diaphragmatic contractility in laboratory animals, but there have been few studies in humans. We have investigated the effect of a single bolus injection of propofol on twitch diaphragmatic pressure (TwPdi) evoked by cervical supramaximal magnetic stimulation, and its impact on diaphragmatic contractility. MethodsIn 16 patients scheduled for elective operation, TwPdi was evoked bilaterally at the cervical phrenic nerves with supramaximal magnetic stimulations using a 140 mm diameter magnetic coil. Changes of TwPdi were monitored dynamically before and during general anaesthesia induced by single bolus of propofol 2 mg kg −1. During the study, all patients breathed 100% oxygen by a face mask, maintaining Spo2 ≥99% and Pe′co2 4.6–5.2 kPa. ResultsTwPdi declined after administration of propofol with gradual recovery. Compared with baseline [20.6 (6.0) cm H2O], TwPdi decreased by 23.3% (P<0.001) to [15.8 (6.4) cm H2O]. When the patients regained awareness, TwPdi returned to [19.1 (6.1) cm H2O], close to baseline (P=0.063). The time from starting the propofol infusion to the lowest TwPdi was [240 (86) s]. Total time course of stimulation lasted [363 (89) s]. ConclusionsA single bolus propofol depressed TwPdi evoked by cervical magnetic stimulation, demonstrating inhibitory effects of propofol on diaphragmatic contractility in patients during general anaesthesia.

Enzyme kinetics and mechanism, by Paul F. Cook and W.W. Cleland

Enzyme kinetics and mechanism, by Paul F. Cook and W.W. Cleland

The in vivo cytokine release profile following implantation

There has been no comprehensive study that maps the production of the range of inflammatory cytokines following implantation of a material. There is an urgent requirement for specific data on the real time production of biological markers in order to study their effects in vitro and more accurately predict the in vivo response. This study determined the production of IL-1β, IL-2, IL-4, IL-6, IL-10, IFNγ and TNF-α in response to a synthetic material implanted in a rat soft tissue model for up to 90 days. IL-1 β and TNF-α were elevated over the total experimental time course with values in the order of 500 pg/ml for IL-1β and 40 pg/ml for TNF-α. The cytokines IL-2, IL-4, IL-6 and IL-10 were also detected and their production reduced with increasing time.

Trapping and Structural Elucidation of an Intermediate in the Macrophomate Synthase Reaction Pathway

Macrophomate synthase (MPS) catalyzes the reaction of oxaloacetate and 2-pyrones to give, over multiple steps, substituted benzoates. We detected a transient intermediate in the course of this transformation by monitoring the total time course either spectroscopically at 305 nm or by 1H NMR. This species was trapped by quenching the reaction with acetonitrile and cooling the sample to 270 K; its structure was determined to be an allylic cyclohexadienol by a complete 2D NMR spectroscopic analysis. It is formed according to Michaelis−Menten kinetics at a rate that is as fast or faster than the decarboxylation of oxaloacetate, the first step in the reaction sequence. Dehydration of this compound to give macrophomate, which limits the rate of the overall process, is not catalyzed by MPS. Although these results clarify the final stages of MPS catalysis, they shed no light on the early C−C bond-forming step(s). As a consequence, other methods will be needed to resolve the controversy as to whether this enzyme f...

Brief antenatal cognitive behaviour therapy group intervention for the prevention of postnatal depression and anxiety: A randomised controlled trial

Background The majority of randomised controlled trials examining the effectiveness of antenatal group interventions at preventing postnatal depression in “at risk” women have used a “psychoeducational” intervention. The aim of the present study is to evaluate the effectiveness of an antenatal cognitive behavioural group intervention in a primary care setting for pregnant women identified with mild to moderate symptoms in pregnancy and/or at risk of developing depression or anxiety in the perinatal period. Method Subjects were randomised to a CBT group intervention or control condition (information booklet) and administered the EPDS and STAI at pre (Time 1) and post intervention (Time 2), and at 2 months (Time 3) and 4 months postpartum (Time 4). MINIs were administered at Times 1, 3 and 4. Results Of the 774 women approached, 277 accepted and were suitable; thus 191 were randomised to the CBT intervention and 86 to the control condition. The subsequent 52% drop-out left 89 women “completing” the CBT groups and 43 in the control group; these two groups were well matched on demographic variables. Intention to treat analyses revealed relatively low mean baseline EPDS scores (means 6.88 -8.16) with no reduction in EPDS scores in either group from Time 1 to Time 4. MINI depression criteria were fulfilled by 19% of all participants at Time 1 but there was no reduction in depression in either group; in contrast those with MINI anxiety diagnoses reduced from 28% in late pregnancy to 16% at four months postpartum in the CBT group with similar reductions in the control group. Analyses on the 132 “completers” showed significant symptomatic improvement over time for both the CBT group and control condition. Depression scores in the most symptomatic women (EPDS > 12; N = 19) decreased steadily by over 50% over the total time course but there were no differences in improvement between the CBT and control groups. Limitations A number of methodological factors may have obscured our results including a tendency to natural remission in mildly symptomatic subjects and the possibility that our control condition was therapeutic in itself. Conclusion While a modest reduction in depression scores was noted in study “completers”, both the CBT group intervention control condition were equally beneficial. The reasons for this finding include the low symptom level at baseline; the potential effectiveness of the control condition; and the brevity of the intervention.

Odontoblast transport of sulphate—the in vitro influence of fluoride

The present study reports the development of a culture system for the analysis of 35 S -sulphate release from odontoblasts in vitro. Pulpless longitudinally split rat incisors were cultured in supplemented minimum essential medium (αMEM) with 20 μCi 35 S -sulphate per ml, 20 μCi 3 H -mannitol per ml for 1 h. Teeth were then transferred to fresh unlabelled media and aliquots of media were removed and the level of 35 S -sulphate 3 H -mannitol determined. Results indicated a two phase release of 35 S -sulphate into the media, and comparison with pulp tissue indicated a specific release pattern. Transport of sulphate is essential for correct synthesis and glycosylation of macromolecules such as proteoglycans (PG). Previous studies have shown that post-translational modifications of these proteins can be influenced by excess fluoride, resulting in decreased sulphation and elongation of glycosaminoglycan (GAG) chains. Therefore the influence of fluoride on sulphate transport, using the optimised culture system was also investigated. Inclusion of 6 mM fluoride during pulse labelling caused a significant decrease of 35 S -sulphate ( P<0.0001) during the initial release phase. Inclusion of 3 and 6 mM fluoride only in the post-labelling incubation media resulted in a significant decrease in the release of 35 S -sulphate ( P<0.0001), during the total time course. The influence of fluoride was not dose dependent. Inclusion of a specific chloride channel blocker SITS, into the culture system indicated that 35 S -sulphate transport may in part be via this route. Fluoride would therefore appear to influence the transport of 35 S -sulphate across the odontoblast membrane, potentially via a chloride channel.

A SAXS/WAXS XAFS study of crystallisation in cordierite glass.

New Cr X-ray absorption fine structure (XAFS) data have been combined with the results of small angle X-ray scattering (SAXS) and wide angle X-ray scattering (WAXS) experiments to probe in detail the crystallisation mechanism in cordierite (Mg2Al4Si5O18) glass doped with 0.34 mol% Cr2O3. By direct comparison with chromo-aluminate spinels (MgCr2xAl2(1 - x)O4) Cr XAFS is used to determine the composition of the devitrified Cr species. This is identified as MgCr(0.18)Al(1.82)O4, which can be directly related to the Cr content in the starting glass and as a result the total crystalline volume in the fully developed ceramic is predicted to be 4%. In situ WAXS not only reveals the presence of the spinel phase but also a silica-rich stuffed quartz phase. This grows independently of the spinel and is probably nucleated from the glass surface. From our knowledge of the compositions of both crystalline phases we are able to deduce that the SAXS contrast between the surrounding glass and the spinel crystallites is 30 times greater than that between the quartz crystallites and the glass matrix, and therefore dominates the measured scattered intensity and the SAXS invariant that is derived from it. As a consequence we are able to show that the spinel crystalline volume fraction inherent in the SAXS is in close agreement with the 4% value obtained from the Cr XAFS. Furthermore in situ SAXS reveals the gradual development of the spinel particle size and shape during heat treatment. This is conducted in the super-cooled region just above the glass transition temperature, Tg. By employing a two-step annealing process nucleation can be separated from growth and from time-resolved SAXS measurements the alumino-chromate nanocrystals are found to be closely monodispersed. Over a total time course of 600 min they grow from rough crystallites to smooth spherical particles of radius 21 +/- 2 nm, with a final density of (1.2 +/- 0.4) x 10(21) m(-3). As the process of ceramic formation takes place in the viscous melt, growth is indeed found to be limited by diffusion and is complete when all the Cr is exhausted. We use this comprehensive in situ study of crystallisation in cordierite glass to demonstrate the advantages of combining SAXS, WAXS and XAFS for probing the time-resolved chemistry, the microstructure and its development from nucleation sites, that underpins the processing of nanoparticle ceramics.

Accelerated inactivation of voltage-dependent K+ outward current in cardiomyocytes from thyroid hormone receptor alpha1-deficient mice.

Thyroid hormone affects the electrophysiologic properties of the heart. It is not known which of the different subtypes of thyroid hormone receptors mediate these effects. Using standard patch-clamp techniques, we studied time- and voltage-dependent properties of depolarization-activated K+ currents in ventricular heart cells isolated from mice lacking the thyroid hormone receptor alpha1 (TR alpha1) and compared these currents with those in respective wild-type cells. In both groups of cells, the time course of current decay could be described by two inactivating exponential components and a sustained current component. In TR alpha1-deficient cells, the total inactivation time course was accelerated due to both increase of the relative contribution of the fast component and shortening of the slow time constant. The peak amplitude of the total current was not altered. The main component of steady-state inactivation of the voltage-dependent K+ outward current was shifted to more hyperpolarized voltages by 7 mV in TR alpha1-deficient cells compared with that in wild-type cells. Under current-clamp conditions, action potential duration at 90% repolarization was prolonged in TR alpha1-deficient cells compared with that in wild-type cells by 3.6 msec. The resulting acceleration of the total inactivation time course is proposed to contribute to action potential prolongation and thus to the increased QTend-time observed previously on ECG of TR alpha1-deficient mice.

Les horaires principaux du circuit dˈun enfant aux urgences pédiatriques. Expérience de lˈhôpital Lenval en 1999

Objective. – The purpose of the present study was to determine the main schedules of a visit in a paediatric emergency ward. Patients and methods. – A prospective survey concerning the main schedules of the children examined in the paediatric emergency ward of the Lenval’s hospital in Nice in 1999 was implemented. The study was conducted over a period of 84 days, one week per month, and included 6038 children analysed recording to the following criteria: 1) duration of the waiting; 2) duration of the radiological period; 3) duration of the medical advice and/or treatment period; 4) total time course of the visit. Results. – Data were collected in 66.6% of all cases for waiting ( n = 4022), 52.1% for medical advice ( n = 3149), in 44.1% for radiological time ( n = 833 of 1888 children having radiological examination), in 58.1% for the total time course of the visit. Waiting for not severe emergencies was about one time out of three less than five minutes, more than one time out of two less than 15 minutes, and more than three times out of four less than 30 minutes. Mean radiological time course was 20 to 25 minutes. Mean medical advice was 15 minutes, for medical consultations such as surgical ones. Total time course of the visit was less than 30 minutes in 23.1% of all cases, 30 to 60 minutes in 38.5%, one to two hours in 31.3%, two to four hours in 6.8%, and more than four hours in 0.3% of all cases. Mean total time course of the visit was 45 minutes for medical emergencies and 55 minutes for surgical ones. Conclusion. – This study shows the main schedules of a visit in a paediatric emergency ward which took care of 26 726 children in 1999. The results of this survey confirmed that waiting before consultation, for not severe emergencies, is sometimes long or very long because of a constant increasing number of patients and their preferential breakdown according to specific periods (weekends, public or school holidays, winter) which are the result of demographic, social and economic changes. At present, the only available possibility to control both phenomena consists in adjusting and adopting medical tools and staffs to crowds and flows. This study also confirms the usefulness for paediatric emergency ward to have a short hospitalization unit.

Convulsions Induced by Ropivacaine During Interscalene Brachial Plexus Block

Convulsions Induced by Ropivacaine During Interscalene Brachial Plexus Block