Pediatric emergency medical care in Yerevan, Armenia: a knowledge and attitudes survey of out-of-hospital emergency physicians.

BACKGROUND: Out-of-hospital emergency care is at an early stage of development in Armenia, with the current emergency medical services (EMS) system having emergency physicians (EPs) work on ambulances along with nurses. While efforts are underway by the Ministry of Health and other organizations to reform the EMS system, little data exists on the status of pediatric emergency care (PEC) in the country. We designed this study to evaluate the knowledge and attitudes of out-of-hospital emergency physicians in pediatric rapid assessment and resuscitation, and identify areas for PEC improvement. METHODS: We distributed an anonymous, self-administered Knowledge and Attitudes survey to a convenience sample of out-of-hospital EPs in the capital, Yerevan, from August to September 2012. RESULTS: With a response rate of 80%, the majority (89.7%) of respondents failed a 10-question knowledge test (with a pre-defined passing score of ≥7) with a mean score of 4.17 ± 1.99 SD. Answers regarding the relationship between pediatric cardiac arrest and respiratory issues, compression-to-ventilation ratio in neonates, definition of hypotension, and recognition of shock were most frequently incorrect. None of the participants had attended pediatric-specific continuing medical education (CME) activities within the preceding 5 years. χ2 analysis demonstrated no statistically significant association between physician age, length of EMS experience, type of ambulance (general vs. resuscitation/critical care), or CME attendance and pass/fail status. The majority of participants agreed that PEC education in Armenia needs improvement (98%), that there is a need for pediatric-specific CME (98%), and that national out-of-hospital PEC guidelines would increase PEC safety, efficiency, and effectiveness (96%). CONCLUSIONS: Out-of-hospital emergency physicians in Yerevan, Armenia are deficient in pediatric-specific emergency assessment and resuscitation knowledge and training, but express a clear desire for improvement. There is a need to support additional PEC training and CME within the EMS system in Armenia

Sonoluminescence and collapse dynamics of multielectron bubbles in helium

Multielectron bubbles (MEBs) differ from gas-filled bubbles in that it is the Coulomb repulsion of a nanometer thin layer of electrons that forces the bubble open rather than the pressure of an enclosed gas. We analyze the implosion of MEBs subjected to a pressure step, and find that despite the difference in the underlying processes the collapse dynamics is similar to that of gas-filled bubbles. When the MEB collapses, the electrons inside it undergo strong accelerations, leading to the emission of radiation. This type of sonoluminescence does not involve heating and ionisation of any gas inside the bubble. We investigate the conditions necessary to obtain sonoluminescence from multielectron bubbles and calculate the power spectrum of the emitted radiation.Comment: 6 figure

Skp2 expression is associated with high risk and elevated Ki67 expression in gastrointestinal stromal tumours

BACKGROUND: Gastrointestinal stromal tumors (GIST) exhibit an unpredictable clinical course and can rapidly progress to lethality. Predictions about the biological behavior of GIST are based on a number of canonical clinical and pathologic parameters whose validity in distinguishing between a benign and a malignant tumour is still imperfect. The aim of our study was to investigate the role of morphologic parameters and expression of cells cycle regulators as prognosticators in GIST. METHODS: We performed an immunohistochemical analysis for Ki67, p27Kip1, Jab1, and Skp2, on a Tissue Microarray (TMA) containing 94 GIST. Expression of the above proteins was correlated to classically used prognosticators, as well as to risk groups. Clinical significance of histologic and immunohistochemical features were evaluated in 59 patients for whom follow-up information was available. RESULTS: Overexpression of Ki67 and Skp2, and p27Kip1 loss directly correlated with the high risk group (p = 0.03 for Ki67 and Skp2, p = 0.05 for p27Kip1). Jab1 expression did not exhibit correlation with risk. In 59 cases provided with clinical follow-up, high cellularity, presence of necrosis, and Ki67 overexpression were predictive of a reduced overall survival in a univariate model. The same parameters, as well as mitotic rate, tumour size, and p27Kip1 loss were indicative of a shortened relapse free survival interval. High cellularity, and high mitotic rate retained their prognostic significance by multivariate analysis. CONCLUSION: Our data suggest that a number of histologic parameters in combination with immunohistochemical expression of cell cycle regulators can facilitate risk categorization and predict biologic behavior in GIST. Importantly this study demonstrates, for the first time, that Skp2 expression correlates with Ki67 expression and high risk in GIST

Echocardiographic findings on aortic stenosis: an observational, prospective, and multi-center registry

Background: The aim of this aortic stenosis registry was to investigate the changes of routine echocardiographic indices and strain in patients with moderate-to-severe aortic stenosis over a 6-month follow-up period. Methods: Our aortic stenosis registry is observational, prospective, multicenter registry of nine countries, with 197 patients with aortic valve area less than 1.5 cm2. The enrolment took place from January to August 2017. We excluded patients with uncontrolled atrial arrhythmias, pulmonary hypertension or cardiomyopathies, as well as those with hemodynamically significant valvular disease other than aortic stenosis. We included patients who did not require intervention and who had a complete follow-up study. Results: In patients with preserved ejection fraction, left ventricular mass has significantly increased between baseline and follow-up studies (218 ± 34 grams vs 253 ± 29 grams, p = 0.02). However, when indexed to body surface area, there was no significant difference. Left ventricular global longitudinal strain significantly decreased (-19.7 ± -4.8 vs (-16.4 vs -3.8, p = 0.01). Left atrial volume was significantly higher at follow-up (p = 0.035). Right ventricular basal diameter and mid-cavity diameter were greater at the follow-up (p = 0.04 and p = 0.035, respectively). Patients with low-flow low-gradient aortic stenosis had significantly lower global longitudinal strain (-12.3% ± -3.9% vs -19.7% ± -4.8%, p = 0.01). Conclusion: Left atrial dilatation is one of the first changes to take place in low-flow low-gradient aortic stenosis patients even when left ventricular dimensions and function remains intact. Global longitudinal strain is an important determinant of left ventricular systolic and diastolic dysfunction and right ventricular function is an important parameter of aortic stenosis assessment. Accordingly, our registry has further shed the light on these indices role as multisite follow-up of aortic stenosis

De novo DNA synthesis using polymerase-nucleotide conjugates.

Oligonucleotides are almost exclusively synthesized using the nucleoside phosphoramidite method, even though it is limited to the direct synthesis of ∼200 mers and produces hazardous waste. Here, we describe an oligonucleotide synthesis strategy that uses the template-independent polymerase terminal deoxynucleotidyl transferase (TdT). Each TdT molecule is conjugated to a single deoxyribonucleoside triphosphate (dNTP) molecule that it can incorporate into a primer. After incorporation of the tethered dNTP, the 3' end of the primer remains covalently bound to TdT and is inaccessible to other TdT-dNTP molecules. Cleaving the linkage between TdT and the incorporated nucleotide releases the primer and allows subsequent extension. We demonstrate that TdT-dNTP conjugates can quantitatively extend a primer by a single nucleotide in 10-20 s, and that the scheme can be iterated to write a defined sequence. This approach may form the basis of an enzymatic oligonucleotide synthesizer

<i>De novo</i> DNA synthesis using polymerasenucleotide conjugates

Oligonucleotides are almost exclusively synthesized using the nucleoside phosphoramidite method, even though it is limited to the direct synthesis of ∼200 mers and produces hazardous waste. Here, we describe an oligonucleotide synthesis strategy that uses the template-independent polymerase terminal deoxynucleotidyl transferase (TdT). Each TdT molecule is conjugated to a single deoxyribonucleoside triphosphate (dNTP) molecule that it can incorporate into a primer. After incorporation of the tethered dNTP, the 3' end of the primer remains covalently bound to TdT and is inaccessible to other TdT-dNTP molecules. Cleaving the linkage between TdT and the incorporated nucleotide releases the primer and allows subsequent extension. We demonstrate that TdT-dNTP conjugates can quantitatively extend a primer by a single nucleotide in 10-20 s, and that the scheme can be iterated to write a defined sequence. This approach may form the basis of an enzymatic oligonucleotide synthesizer

De novo DNA synthesis using polymerase-nucleotide conjugates.

Oligonucleotides are almost exclusively synthesized using the nucleoside phosphoramidite method, even though it is limited to the direct synthesis of ∼200 mers and produces hazardous waste. Here, we describe an oligonucleotide synthesis strategy that uses the template-independent polymerase terminal deoxynucleotidyl transferase (TdT). Each TdT molecule is conjugated to a single deoxyribonucleoside triphosphate (dNTP) molecule that it can incorporate into a primer. After incorporation of the tethered dNTP, the 3' end of the primer remains covalently bound to TdT and is inaccessible to other TdT-dNTP molecules. Cleaving the linkage between TdT and the incorporated nucleotide releases the primer and allows subsequent extension. We demonstrate that TdT-dNTP conjugates can quantitatively extend a primer by a single nucleotide in 10-20 s, and that the scheme can be iterated to write a defined sequence. This approach may form the basis of an enzymatic oligonucleotide synthesizer