Project description:BACKGROUND:Management of spontaneous pneumothorax (SP) is still subject to debate. Although encouraging results of recent studies about outpatient management with chest drains fitted with a one-way valve, no data exist concerning application of this strategy in real life conditions. We assessed how SP are managed in Emergency departments (EDs), in particular the role of outpatient management, the types of interventions and the specialty of the physicians who perform these interventions. METHODS:From June 2009 to May 2013, all cases of spontaneous primary (PSP) and spontaneous secondary pneumothorax (SSP) from EDs of 14 hospitals in France were retrospectively included. First line treatment (observation, aspiration, thoracic drainage or surgery), type of management (admitted, discharged to home directly from the ED, outpatient management) and the specialty of the physicians were collected from the medical files of the ED. RESULTS:Among 1868 SP included, an outpatient management strategy was chosen in 179 PSP (10%) and 38 SSP (2%), mostly when no intervention was performed. Only 25 PSP (1%) were treated by aspiration and discharged to home after ED admission. Observation was the chosen strategy for 985 patients (53%). In 883 patients with an intervention (47%), it was performed by emergency physicians in 71% of cases and thoracic drainage was the most frequent choice (670 patients, 76%). CONCLUSIONS:Our study showed the low level of implementation of outpatient management for PS in France. Despite encouraging results of studies concerning outpatient management, chest tube drainage and hospitalization remain preponderant in the treatment of SP.
Project description:BACKGROUND: Expectant management is an alternative for curettage in women with a miscarriage. AIM: To assess the pattern of vaginal bleeding and pain in expectantly managed women with a miscarriage, and to analyse the factors predictive of a relatively quick spontaneous loss of pregnancy. DESIGN OF STUDY: Part of a study comparing expectant management with surgical evacuation. SETTING: Two hospitals in Amsterdam. METHOD: In expectantly managed women with a miscarriage, the pattern of vaginal bleeding and pain and the probability of a spontaneous loss of pregnancy was analysed. RESULTS: Of the 188 expectantly managed women 95 (51%) experienced a spontaneous loss of their pregnancy. In women with bleeding at inclusion, 52% had a completed miscarriage loss, while of the women without bleeding but with a coincidentally diagnosed non-viable pregnancy during routine ultrasonographic examination, 46% had a completed miscarriage. In the multivariate analysis an increasing bleeding pattern at inclusion was predictive of a relatively quick spontaneous loss of pregnancy. The median daily levels of bleeding and pain were the most prominent during the first 8 days after the start of the bleeding and decreased thereafter. CONCLUSIONS: Expectant management is effective in 51% of unselected women with a miscarriage. An increasing bleeding pattern is predictive of a relatively quick spontaneous loss of pregnancy in first-trimester miscarriages. The graphical representation of our findings can be used to inform women about the natural course of miscarriages and a well-informed treatment choice.
Project description:In cells, RNA polymerase (RNAP) must transcribe supercoiled DNA, whose torsional state is constantly changing, but how RNAP deals with DNA supercoiling remains elusive. We report direct measurements of individual Escherichia coli RNAPs as they transcribed supercoiled DNA. We found that a resisting torque slowed RNAP and increased its pause frequency and duration. RNAP was able to generate 11 ± 4 piconewton-nanometers (mean ± standard deviation) of torque before stalling, an amount sufficient to melt DNA of arbitrary sequence and establish RNAP as a more potent torsional motor than previously known. A stalled RNAP was able to resume transcription upon torque relaxation, and transcribing RNAP was resilient to transient torque fluctuations. These results provide a quantitative framework for understanding how dynamic modification of DNA supercoiling regulates transcription.
Project description:Introductionand importance: We reported a case of secondary spontaneous pneumothorax (SSP) in a 70-years-old male with acute exacerbation of COPD (AE COPD) managed with improvised chest tube drain (ICD).Case presentationHe presented with sudden onset breathlessness and oxygen saturation of 78%. With prolonged expiration on auscultation, he was treated as AE COPD with oxygen therapy, nebulization with albuterol/ipratropium, and injectable antibiotics and steroids. The patient was not improving with treatment on third day, and non-critical respiratory distress continued. Considering the alternative diagnosis, the chest X-ray was done which revealed right sided spontaneous pneumothorax and COPD. Due to his reluctancy to go to higher center for chest tube insertion during ongoing COVID-19 pandemic, we inserted ICD (intravenous set put in saline bottle) at our primary care. Following drainage, breathlessness improved and saturation increased. Then inpatient symptomatic treatment for COPD was continued for three more days. He was discharged on inhalers after fifth day and asked for follow up after 10 days. He came after 1 month and on repeat chest X-ray, his right sided pneumothorax resolved completely and COPD was in control with inhaled medications. There was no recurrence of pneumothorax in five months follow up.Clinical discussionICD is a safe, and an alternative option in resource limited setting. However, the guidelines recommend chest tube insertion as appropriate treatment.ConclusionThis would remind the physicians to anticipate the alternative possibility, and to re-examine those with AE COPD who are not improving as expected with oxygen and nebulization therapy.
Project description:BACKGROUND:To determine the inter-study reproducibility of MR feature tracking (MR-FT) derived left ventricular (LV) torsion and torsion rates for a combined assessment of systolic and diastolic myocardial function. METHODS:Steady-state free precession (SSFP) cine LV short-axis stacks were acquired at 9:00 (Exam A), 9:30 (Exam B), and 14:00 (Exam C) in 16 healthy volunteers at 3 Tesla. SSFP images were analyzed offline using MR-FT to assess rotational displacement in apical and basal slices. Global peak torsion, peak systolic and peak diastolic torsion rates were calculated using different definitions ("twist", "normalized twist" and "circumferential-longitudinal (CL) shear angle"). Exam A and B were compared to assess the inter-study reproducibility. Morning and afternoon scans were compared to address possible diurnal variation. RESULTS:The different methods showed good inter-study reproducibility for global peak torsion (intraclass correlation coefficient [ICC]: 0.90-0.92; coefficient of variation [CoV]: 19.0-20.3%) and global peak systolic torsion rate (ICC: 0.82-0.84; CoV: 25.9-29.0%). Conversely, global peak diastolic torsion rate showed little inter-study reproducibility (ICC: 0.34-0.47; CoV: 40.8-45.5%). Global peak torsion as determined by the CL shear angle showed the best inter-study reproducibility (ICC: 0.90;CoV: 19.0%). MR-FT results were not measurably affected by diurnal variation between morning and afternoon scans (CL shear angle: 4.8 ± 1.4°, 4.8 ± 1.5°, and 4.1 ± 1.6° for Exam A, B, and C, respectively; P = 0.21). CONCLUSION:MR-FT based derivation of myocardial peak torsion and peak systolic torsion rate has high inter-study reproducibility as opposed to peak diastolic torsion rate. The CL shear angle was the most reproducible parameter independently of cardiac anatomy and may develop into a robust tool to quantify cardiac rotational mechanics in longitudinal MR-FT patient studies.
Project description:DNA torsional stress is generated by virtually all biomolecular processes involving the double helix, in particular transcription where a significant level of stress propagates over several kilobases. If another promoter is located in this range, this stress may strongly modify its opening properties, and hence facilitate or hinder its transcription. This mechanism implies that transcribed genes distant of a few kilobases are not independent, but coupled by torsional stress, an effect for which we propose the first quantitative and systematic model. In contrast to previously proposed mechanisms of transcriptional interference, the suggested coupling is not mediated by the transcription machineries, but results from the universal mechanical features of the double-helix. The model shows that the effect likely affects prokaryotes as well as eukaryotes, but with different consequences owing to their different basal levels of torsion. It also depends crucially on the relative orientation of the genes, enhancing the expression of eukaryotic divergent pairs while reducing that of prokaryotic convergent ones. To test the in vivo influence of the torsional coupling, we analyze the expression of isolated gene pairs in the Drosophila melanogaster genome. Their orientation and distance dependence is fully consistent with the model, suggesting that torsional gene coupling may constitute a widespread mechanism of (co)regulation in eukaryotes.
Project description:How the methyl torsion transition energy in unsaturated systems is affected by its environment is investigated. It is strongly influenced by both its immediate neighborhood, (the number of methyl groups present in the molecule) and the intermolecular interactions. It is clear that the intermolecular interactions have a major influence on the torsion transition energy, as demonstrated unambiguously previously for mesitylene and also seen here for other systems. In part, this may be caused by the fact that the methyl torsion is rarely a pure mode (unless enforced by symmetry). Where the crystal structure is available, the assignments have been supported by CASTEP calculations of the unit cell. The agreement between the observed and calculated spectra is generally good, although not perfect, toluene being a case in point, and highlights just how demanding it is to obtain accurate transition energies for low energy modes. The disagreement between observed and calculated inelastic neutron scattering spectra for meta-xylene and 9,10 dimethylanthracene is so severe that it would suggest that there are additional phases to those presently known. Comparison between the full periodic calculations and those for the isolated molecule shows that intermolecular interactions raise the methyl torsion transition energy by at least 8% and in some cases by more than 50%. The presence of more than one methyl group in the molecule generally raises the average torsion energy from the <100 cm-1 seen for single methyl groups to 150-200 cm-1.
Project description:A 17-year-old boy presented with right testicular torsion to the lateral side. Torsion was diagnosed by physical examination; the colour Doppler ultrasonography (CDU) confirmed right testicular torsion with minimal peripheral hydrocele. Transverse and longitudinal examination of the spermatic cord with ultrasound and CDU revealed a counter-clockwise testicular torsion. Manual de-torsion was performed in a clockwise direction (720o) and testicular blood flow and the neutral position of the spermatic cord were confirmed by CDU. We did not encounter a residual twist of the spermatic cord upon surgical exploration. In our experience, ultrasound and CDU may predict the direction of testicular torsion and may allow appropriate management of cases prior to surgery.