Cyanobacterial growth and cyanophycin production with urea and ammonium as nitrogen source

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Médecine d’urgence [Emergency medicine : update 2019]

At a time when « Smarter medicine » and « Choosing Wisely » campains become increasingly important, emergency medicine is no exception. Many recent studies lead us to reconsider our practices and to change our work-up and treatement strategies, to ultimately use only the ones with a real clinical benefit for emergency departement patients

The discovery of endogenous retroviruses

When endogenous retroviruses (ERV) were discovered in the late 1960s, the Mendelian inheritance of retroviral genomes by their hosts was an entirely new concept. Indeed Howard M Temin's DNA provirus hypothesis enunciated in 1964 was not generally accepted, and reverse transcriptase was yet to be discovered. Nonetheless, the evidence that we accrued in the pre-molecular era has stood the test of time, and our hypothesis on ERV, which one reviewer described as 'impossible', proved to be correct. Here I recount some of the key observations in birds and mammals that led to the discovery of ERV, and comment on their evolution, cross-species dispersion, and what remains to be elucidated

Nausées et vomissements chez la femme enceinte [Nausea and vomiting in pregnancy]

Nausea and vomiting in early pregnancy is a common condition at risk to be minimized by women or care providers. If not treated in the early stages, it can evolve to a severe condition with a morbidity risk for the mother and/or the fetus, and expose to public health consequences. Severe forms of nausea and vomiting and hyperemesis gravidarum are a clinical diagnosis with nonspecific manifestations in addition to biologic and metabolic consequences for mother and/or child. Safe and effective treatments can prevent severe consequences if used in an early stage of symptoms

Understanding Decline in Medical Video Consultation - A User-Centred Approach.

The world’s population is growing and ageing. Consequently, the demand for health care services increases, which leads to the need for health care providers to find new ways to provide services. Video consultations (VCs) are a cost-efficient way to address this problem. However, they can only work if both health professionals and patients trust and make use of VC systems. We describe our work on determining the reasons behind why the use of VC declined after an initial period of intensive use at a local Dutch medical centre. Questioning patients why they no longer contact their doctors via video was not possible as it would violate privacy law. We propose an alternative method that combines interviews with medical professionals and vignette studies, which can be used to follow up with patients potentially using VCs. We provide a set of lessons learned, which can support future inquiries in the medical domain

Cyanobacterial growth and cyanophycin production with urea and ammonium as nitrogen source

Several technologies have aimed to recover nitrogen directly from urine. Nitrogen recovery in these technologies was limited by the mismatch of the nitrogen-phosphorus molar ratio (N:P) of urine, being 30–46:1, and that of the final product, e.g., 1:1 in struvite and 16–22:1 in microalgae biomass. Additionally, the high nitrogen concentrations found in urine can be inhibitive for growth of microorganisms. Cyanobacteria were expected to overcome phosphorus (P) limitation in urine given their ability to store an N-rich polymer called cyanophycin. In this study, it was found that the model cyanobacterium Synechocystis sp. PCC6803 did not experience significant growth inhibition when cultivated in synthetic medium with concentrations of 0.5 g ammonium-N L−1. In the case of urea, no inhibition was observed when having it as sole nitrogen source, but it resulted in chlorosis of the cultures when the process reached stationary phase. Synechocystis was successfully cultivated in a medium with 0.5 g ammonium-N L−1 and a N:P ratio of 276:1, showing the N:P flexibility of this biomass, reaching biomass N:P ratios up to 92:1. Phosphorus starvation resulted in cyanophycin accumulation up to 4%. Dilution of the culture in fresh medium with the addition of 118 mg N L−1 and 1.5 mg P L−1 (N:P of 174:1) resulted in a rapid and transient cyanophycin accumulation up to 11%, after which cyanophycin levels rapidly decreased to 3%

Médecine d’urgence : update 2018 [Emergency medicine : update 2018]

Professionalisation of emergency medicine is currently booming. In order to offer the best care, emergency physician can refer to several new studies : 1) in a cerebral stroke, the 0° head position doesn't offer any benefit ; 2) hyperoxygenation in acute patients could raise mortality ; 3) epinephrine in prehospital cardiac arrest favors return of spontaneous circulation but worsens the neurological prognosis ; 4) systematic cross-checking reduces the risk of adverse events in the emergency department ; 5) ultrasensitive troponins better detect myocardic events, but raises the number of unusefull invasive procedures and 6) combined pre-test probability score and D-dimers potentially allows to rule out aortic dissection