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Notes: Abstract A 15-year-old girl was admitted to ICU in a comatose state. She presented with mydriasis, areflexia, hypoxemia and seizures. She was immediately intubated and connected to a ventilator. The seizures were reversed with intravenous diazepam. CT scan was negative. EEG showed a diffuse fast activity and theta waves with spikes in the anterior and temporal regions, bilaterally. The gastric lavage was suggestive of drug ingestion. The patient completely recovered after 6 h of mechanical ventilation and supportive management. Mydriasis was still present after the resolution of neurological symptoms. The girl told us she had ingested 10 tablets (3 g–55 mg/kg) of Loftyl (buflomedil) for suicidal intention. The buflomedil concentrations at 2–3 h from ingestion were 24.8 mg/l in the blood, 324.4 mg/l in the urine and 6.9 mg/l in the gastric content. The p-desmethyl metabolite was also identified in the urine. Buflomedil is a rheological agent largely used as a vasodilator in some European countries. Some recent reports have emphasized the risk of acute intoxication with this drug. Relatively low doses (50–60 mg/kg) have been associated with an important neurological toxicity and a high mortality. We suggest that the clinical picture we observed might be related to a neuroleptic-type action of buflomedil. We bring to attention the risk of a large, uncontrolled diffusion of a drug capable to cause serious consequences at relatively low doses.

Notes: Abstract Objective The purpose of this study was to investigate whether changes in breathing pattern, neuromuscular drive (P0.1), and the work involved in breathing might help to set the individual appropriate level of pressure support ventilation (PSV) in patients with acute respiratory failure (ARF) requiring ventilatory assistance.Design: A prospective, interventional study. Setting An 8-bed multidisciplinary intensive care unit (ICU). Patients Ten patients with ARF due to adult respiratory distress syndrome (ARDS), sepsis or airway infection were included in the study. Chronic obstructive pulmonary disease (COPD) patients with acute exacerbation were excluded. None of these patients was in the weaning process. Interventions We found a level of pressure support able to generate a condition of near-relaxation in each patient, as evidenced by work of breathing (WOB) values close to 0 J/l. This level was called PS 100 and baseline physiological measurements, namely, breathing pattern, P 0.1 and WOB were obtained. Pressure support was then reduced to 85%, 70% and 50% of the initial value and the same set of measurements was obtained. Measurements and results Flow ( $$\dot V$$ ) was measured by a flow sensor (Varflex) positioned between the Y-piece of the breathing circuit and the endotracheal tube. Tidal volume was obtained by numerical integration of the flow signal. Airway pressure (Paw) was sampled through a catheter attached to the flow sensor. Esophageal pressure (Pes) was measured with a nasogastric tube incorporating an esophageal balloon. The esophageal balloon and flow and pressure sensors were connected to a portable monitor (CP 100 Bicore) that provided realtime display of flow, volume, Paw and Pes tracings and loops of Pes/V, Paw/V and $$\dot V$$ /V relationships. The breathing pattern was analyzed from the flow signal. Patient work of breathing (WOB) was calculated by integration of the area of the Pes/V loop. Respiratory drive (P 0.1) was measured at the esophageal pressure change during the first 100 ms of a breath, by the quasiocclusion technique. When pressure support was reduced, we found that the respiration rate significantly increased from PS 100 to PS85, but varied negligibly with lower pressure support levels. Tidal volume behaved in a similar way, decreasing significantly from PS 100 to PS85, but hardly changing at PS 70 and PS 50. In contrast, WOB and P 0.1 increased progressively with decreasing pressure support levels. The changes in WOB were significant at each stage in the trial, whereas P 0.1 increased significantly from PS 100 at other stages. Linear regression analysis revealed a highly positive, significant correlation between WOB and P 0.1 at decreasing PSV levels (r=0.87), whereas the correlation between WOB and ventilatory frequency was less significant (r=0.53). No other correlation was found. Conclusions During pressure support ventilation, P 0.1 may be a more sensitive parameter than the assessment of breathing pattern in setting the optimal level of pressure support in individual patients. Although P 0.1 was measured with an esophageal balloon in the present study, non-invasive techniques can also be used.

Notes: [Auszug] Arising from: S. R. Kulkarni et al. Nature 447, 458–460 (2007) An anomalous transient in the early Hubble-type (S0) galaxy Messier 85 (M85) in the Virgo cluster was discovered by Kulkarni et al. on 7 January 2006 that had very low ...

Notes: [Auszug] The death of massive stars produces a variety of supernovae, which are linked to the structure of the exploding stars. The detection of several precursor stars of type II supernovae has been reported (see, for example, ref. 3), but we do not yet have direct information on the ...

Notes: A technique for sorting live LH- and FSH-secreting cells was developed. After enzymatic dispersion, a suspension of pituitary cells from male rats castrated 7 days earlier was incubated in potassium chloride (KCI 50 mmol/l) for 30 min and gonadotropin outflow was provoked. Then, considering either LH or FSH as temporary surface markers, we positively selected the secreting cells by means of antibodies toward either LH (anti-LH beads) or FSH (anti-FSH beads) covalently attached to magnetic beads. The spontaneous secretion of LH and FSH overnight and the release induced by KCI the following morning were calculated. A population enriched in gonadotropes (16% of the total) able to secrete both gonadotropins was selected by means of anti-LH beads; this released 7 times as much LH as non-selected cells. A similar population (14% of the total) was selected by means of anti-FSH-coated beads; this produced 3.3 times as much LH as non-selected cells.In some experiments, the cells not previously sorted with anti-LH-coated beads were further incubated in the presence of anti-FSH beads, in an attempt to isolate a population secreting only FSH. A limited number of cells were sorted (6% of the total cells), able to produce both gonadotropins, but with a lower LH/FSH ratio.Similarly, those cells excluded by the selection with anti-FSH beads were further incubated with anti-LH beads, with a view to obtaining only-LH-secreting cells. However, both gonadotropins were still secreted by these cells (8% of the total), which had the highest LH/FSH ratio.In conclusion, fractions from castrated male rats that are enriched in gonadotropes contain cells that secrete both gonadotropins in vitro. The secretion of LH is prevalent. However, differences in the LH/FSH ratio between the populations sorted and changes from spontaneous to stimulated release are observed. This suggests that some gonadotropes might ‘specialize’ in releasing LH and others in releasing both LH and FSH.

Notes: Abstract Two patients with refractory hypoxemia due to unilateral lung atelectasis were treated with differential lung ventilation (DLV) through a Robertshaw-type, double-lumen tracheostomy tube. DLV was applied using two non-synchronized ventilators and maintained for 6 and 3 days, respectively. Ventilator settings were chosen in accord to the clinical, laboratory and chest X-rays results. Particularly, tidal volume and PEEP were set to avoid excessively high alveolar pressure and to obtain the highest possible value of compliance. We investigated the mechanical properties of the two lungs separately by measuring airway pressure and compliance of each lung before the beginning of DLV and at 0, 5, 24, and 48 h after. Initially we observed in both patients very low values of compliance (7–9 cm H2O/I) and a significant level of PEEPi (12–8 cm H2O) of the diseased lung, whereas PEEPi in the healthy lung was negligible. The clinical improvement was assessed by sequential chest X-rays and by significant improvement of arterial blood gas and PaO2/FiO2 ratios and was associated with a progressive increase of compliance (24–22 cm H2O/I) and by a fall of PEEPi levels (5–4 cm H2O) of the diseased lung. We also observed an improvement of S $$\bar v$$ O2, O2AVI, PVRI and $$\dot Q$$ va/ $$\dot Q$$ t values (Case 1). The tracheostomy tube used to apply DLV was very reliable, allowing easy nursing care and selective bronchial aspirations. We conclude that DLV is a very useful technique in unilateral lung pathology, and it can be a life saving procedure in selected patients, by supplying volume and PEEP more efficiently to the affected lung.

Notes: Abstract After a rigorous introduction to hyperreal numbers, we give in terms of non standard analysis, (1) a Lagrangian statement of classical physics, and (2) a statement of formal quantum scattering.