Suberization-the second life of an endodermal cell.

The endodermis is the innermost cortical cell layer that surrounds the central vasculature and deposits an apoplastic diffusion barrier known as the Casparian strip. Although discovered 150 years ago, the underlying mechanisms responsible for formation of the Casparian strips have only recently been investigated. However, the fate of the endodermal cell goes further than formation of Casparian strips as they undergo a second level of differentiation, defined by deposition of suberin as a secondary cell wall. The presence and function of endodermal suberin in root barriers has remained enigmatic, as its role in barrier formation is not clear, especially in respect to the already existing Casparian strips. In this review, we present recent advances in the understanding of suberin synthesis, transport to the secondary cell wall, developmental features and functions. We focus on some of the major unknown questions revolving the function of endodermal suberin, which we now have the means to investigate. We further provide thoughts on how this knowledge might expand our current models on the developmental and physiological adaptation of root in response to the environment.

The impact of an enhanced recovery pathway on nursing workload: A retrospective cohort study.

BACKGROUND & AIMS: The importance of nursing for surgical patients has been frequently underestimated. The success of enhanced recovery programs after surgery (ERAS) depends on preferably complete fulfilment of the protocol and nurses are an important part of it. Due to the additional nursing action required, such protocols are suspected to increase the nursing workload. The aim of the present study was to observe and measure objectively nursing workload before, during and after systematic implementation of a comprehensive enhanced recovery pathway in colorectal surgery. METHODS: The program ERAS was introduced systematically in our tertiary academic centre 2011, since then our experience is based on more than 1500 ERAS patients. Nursing workload was prospectively assessed for all patients on a routine basis by means of a standardized and validated point system (PRN). In a retrospective cohort study, we compared nursing workload based on prospective data before, during and after ERAS implementation and correlated nursing workload to the compliance with the ERAS protocol. RESULTS: The study cohort included 50 patients before ERAS implementation (2010) and 69 (2011) and 148 (2012) consecutive patients after implementation; the baseline characteristics of the 3 groups were similar. Mean PRN values were 61.2 ± 19.7 per day in 2010 and decreased to 52.3 ± 13.7 (P = 0.005) and 51.6 ± 18.6 (P < 0.002) in 2011 and 2012, respectively. Increasing compliance with the ERAS protocol was significantly correlated to decreasing nursing workload (ρ = -0.42; P < 0.001). CONCLUSIONS: Nursing workload is - against a common belief - decreased by systematic implementation of enhance recovery protocol. The higher the compliance with the pathway, the lower the burden for the nurses!

Cost-benefit analysis of an enhanced recovery protocol for pancreaticoduodenectomy.

BACKGROUND: Enhanced recovery after surgery (ERAS) programmes have been shown to decrease complications and hospital stay. The cost-effectiveness of such programmes has been demonstrated for colorectal surgery. This study aimed to assess the economic outcomes of a standard ERAS programme for pancreaticoduodenectomy. METHODS: ERAS for pancreaticoduodenectomy was implemented in October 2012. All consecutive patients who underwent pancreaticoduodenectomy until October 2014 were recorded. This group was compared in terms of costs with a cohort of consecutive patients who underwent pancreaticoduodenectomy between January 2010 and October 2012, before ERAS implementation. Preoperative, intraoperative and postoperative real costs were collected for each patient via the hospital administration. A bootstrap independent t test was used for comparison. ERAS-specific costs were integrated into the model. RESULTS: The groups were well matched in terms of demographic and surgical details. The overall complication rate was 68 per cent (50 of 74 patients) and 82 per cent (71 of 87 patients) in the ERAS and pre-ERAS groups respectively (P = 0·046). Median hospital stay was lower in the ERAS group (15 versus 19 days; P = 0·029). ERAS-specific costs were euro922 per patient. Mean total costs were euro56 083 per patient in the ERAS group and euro63 821 per patient in the pre-ERAS group (P = 0·273). The mean intensive care unit (ICU) and intermediate care costs were euro9139 and euro13 793 per patient for the ERAS and pre-ERAS groups respectively (P = 0·151). CONCLUSION: ERAS implementation for pancreaticoduodenectomy did not increase the costs in this cohort. Savings were noted in anaesthesia/operating room, medication and laboratory costs. Fewer patients in the ERAS group required an ICU stay.

Efficacy of an eradication schema in case of Pseudomonas aeruginosa primo-infection in children with cystic fibrosis

Introduction: Patients with Cystic fibrosis (CF) are more susceptible to pathogens like P. aeruginosa (PA). PA primo-infection requires particular attention as failure in eradication is associated with accelerated lung deterioration. The main aim of this study is to assess the rate of PA eradication according to our particular protocol with inhaled tobramycin and oral ciprofloxacin, as there is no consensus in the literature on what eradication protocol is optimal. Methods: Retrospective single centre study with data analysis from June 1st 2007 to June 1st 2011 of patients with PA primo-infection exclusively treated by 3 x 28 days of inhaled tobramycin and oral ciprofloxacin for the first and last 21 days. Success in eradication is defined by ≥ 3 negative bacteriologies for 6 months after the beginning of the protocol. If ≥ 1 bacteriology is positive, we consider the eradication as a failure. Results: Out of 41 patients, 18 followed the eradication protocol and were included in our analysis (7 girls (38.9%) and 11 boys (61.1%)). Boys had 12 primo-infections and girls had 8. Among these 20 primo-infections, 16 (80%) had an overall success in eradication and 4 (20%) a failure. There was no significant statistical differences in age between these groups (t-test = 0.07, p = 0.94), nor for FEV1% (t-test = 0.96, p = 0.41) or BMI (t-test = 1.35, p = 0.27). Rate of success was 100% for girls and 66.6% for boys. Conclusion: Our protocol succeeded in an overall eradication rate of 80%, without statistical significant impact on FEV1 % and BMI values. However, there was a sex difference with eradication rates in girls (100%) and boys (66.6%). A sex difference has not yet been reported in the literature. This should be evaluated in further studies.

On the use of an appropriate TdT-mediated dUTP-biotin nick end labeling assay to identify apoptotic cells.

Apoptosis is an essential cellular mechanism involved in many processes such as embryogenesis, metamorphosis, and tissue homeostasis. DNA fragmentation is one of the key markers of this form of cell death. DNA fragmentation is executed by endogenous endonucleases such as caspase-activated DNase (CAD) in caspase-dependent apoptosis. The TUNEL (TdT-mediated dUTP-biotin nick end labeling) technique is the most widely used method to identify apoptotic cells in a tissue or culture and to assess drug toxicity. It is based on the detection of 3'-OH termini that are labeled with dUTP by the terminal deoxynucleotidyl transferase. Although the test is very reliable and sensitive in caspase-dependent apoptosis, it is completely useless when cell death is mediated by pathways involving DNA degradation that generates 3'-P ends as in the LEI/L-DNase II pathway. Here, we propose a modification in the TUNEL protocol consisting of a dephosphorylation step prior to the TUNEL labeling. This allows the detection of both types of DNA breaks induced during apoptosis caspase-dependent and independent pathways, avoiding underestimating the cell death induced by the treatment of interest.

L-Lactate protects neurons against excitotoxicity: implication of an ATP-mediated signaling cascade.

Converging experimental data indicate a neuroprotective action of L-Lactate. Using Digital Holographic Microscopy, we observe that transient application of glutamate (100 μM; 2 min) elicits a NMDA-dependent death in 65% of mouse cortical neurons in culture. In the presence of L-Lactate (or Pyruvate), the percentage of neuronal death decreases to 32%. UK5099, a blocker of the Mitochondrial Pyruvate Carrier, fully prevents L-Lactate-mediated neuroprotection. In addition, L-Lactate-induced neuroprotection is not only inhibited by probenicid and carbenoxolone, two blockers of ATP channel pannexins, but also abolished by apyrase, an enzyme degrading ATP, suggesting that ATP produced by the Lactate/Pyruvate pathway is released to act on purinergic receptors in an autocrine/paracrine manner. Finally, pharmacological approaches support the involvement of the P2Y receptors associated to the PI3-kinase pathway, leading to activation of KATP channels. This set of results indicates that L-Lactate acts as a signalling molecule for neuroprotection against excitotoxicity through coordinated cellular pathways involving ATP production, release and activation of a P2Y/KATP cascade.

Evolution: the end of an ancient asexual scandal.

Bdelloid rotifers were believed to have persisted and diversified in the absence of sex. Two papers now show they exchange genes with each other, via horizontal gene transfers as known in bacteria and/or via other forms of non-canonical sex.

Is the presence of an intrathecal synthesis of immunoglobulins associated with neurocognitive impairment in HIV-infected patients?

Worldwide, the incidence of HIV-associated dementia has decreased However, the prevalence of HIV-associated neurocognitive disorders (HAND), mostly the milder forms, i.e. mild neurocognitve disorders (MND) and asymptomatic neurocognitive impairments (ANI) has increased in the combined antiretroviral therapy (cART) era. Indeed, 20% to 60% of well- treated HIV-infected patients, i.e. with undetectable HIV viremia, still present HAND in the cART era. HAND are characterized by psychomotor slowing, memory loss, and attention deficit. Possible explanations for this paradoxical phenomenon encompass: increased survival of HIV- infected patients thank to cART, low grade inflammation of the brain insufficient penetrance of antiretroviral drugs through the blood brain barrier (BBB), or on the contrary, toxic effect of some antiretroviral drugs. These somewhat contradictory hypotheses underline our poor understanding of HAND physiopathology. Here, we aim at determining whether the intrathecal synthesis of immunoglobulins G (IgG), hereafter referred as cerebrospinal fluid oligoclonal band (CSF OB), may help us in better understanding the immunopathogenesis of cognitive disorders. By analogy with other infection, such as syphilis or neuroborreliosis (9, 10), one can assume that, in the case of HIV-infected patients, the CSF OB are directed against HIV proteins (11). Nevertheless, in the case of HIV, the meaning of such CSF OB is unclear. Indeed, it is unknown whether this intrathecal inflammatory reaction is beneficial (viral control) or harmful (brain parenchyma destruction by the different inflammatory factors). Here, we looked at the association between CSF OB and cognitive disorders in HIV-infected patients, hypothesizing that if these CSF OB are protective, one should see an inverse correlation with the presence of cognitive disorders.