Rationalisation of the purification process for a phage active pharmaceutical ingredient.

The resurgence of phage therapy, once abandoned in the early 20th century in part due to issues related to the purification process and stability, is spurred by the global threat of antibiotic resistance. Engineering advances have enabled more precise separation unit operations, improving overall purification efficiency. The present review discusses the physicochemical properties of impurities commonly found in a phage lysate, e.g., contaminants, phage-related impurities, and propagation-related impurities. Differences in phages and bacterial impurities properties are leveraged to elaborate a four-step phage purification process: clarification, capture and concentration, subsequent purification and polishing. Ultimately, a framework for rationalising the development of a purification process is proposed, considering three operational characteristics, i.e., scalability, transferability to various phages and duration. This guide facilitates the preselection of a sequence of unit operations, which can then be confronted with the expected impurities to validate the theoretical capacity of the process to purify the phage lysate.

Maintaining the knowledge and neonatal resuscitation skills of student midwives 6 months after an educational program.

BACKGROUND: Training student midwives in neonatal resuscitation is essential because the midwife is present at every birth and must be able to perform resuscitation procedures when needed. The objective of this study was to evaluate student midwives' retention of theoretical knowledge about resuscitation as well as their practical application of that knowledge 6 months after training. METHOD: A cross-sectional study was conducted for two consecutive years, 2015 and 2016, among 49 student midwives in the middle of their second and final year of training at the University of Applied Sciences in Western Switzerland. The study included assessments of both theoretical knowledge and practical skills regarding neonatal resuscitation 6 months after each participant had completed the training program. The students' theoretical knowledge was evaluated using a multiple-choice question (MCQ) test, the results of which were compared with results from the same MCQ test that had been obtained 6 months earlier. The students' practical skills were evaluated following a simulation workshop by analyzing recorded videos and applying scores using an adapted validated grid. RESULTS: The MCQ pretest and MCQ posttest (after 6 months) scores showed no statistically significant difference (z=-1.583, P=0.113). In terms of the practical skills assessment, 25% of the students (11/44) were considered insufficiently skilled for the table preparation. During the simulation, 22 teams of students were available for analysis. Of these, 11 teams (50.0%) were considered insufficiently skilled. The skills observation findings showed an integration of technical gestures for the majority of the teams, but the items demonstrated a lack of organization and management. CONCLUSION: Neonatal resuscitation training for student midwives shows that their theoretical knowledge seems to be well assimilated while practical skills are unevenly retained. Certain elements, as indicated by the detail of the analysis grid, need to be reinforced by additional workshops before the end of the training.

Assessing toxicity of metal contaminated soil from glassworks sites with a battery of biotests.

The present study addresses toxicological properties of metal contaminated soils, using glassworks sites in south-eastern Sweden as study objects. Soil from five selected glassworks sites as well as from nearby reference areas were analysed for total and water-soluble metal concentrations and general geochemical parameters. A battery of biotests was then applied to assess the toxicity of the glassworks soil environments: a test of phytotoxicity with garden cress (Lepidium sativum); the BioTox™ test for toxicity to bacteria using Vibrio fischeri; and analyses of abundancies and biomass of nematodes and enchytraeids. The glassworks- and reference areas were comparable with respect to pH and the content of organic matter and nutrients (C, N, P), but total metal concentrations (Pb, As, Ba, Cd and Zn) were significantly higher at the former sites. Higher metal concentrations in the water-soluble fraction were also observed, even though these concentrations were low compared to the total ones. Nevertheless, toxicity of the glassworks soils was not detected by the two ex situ tests; inhibition of light emission by V. fischeri could not be seen, nor was an effect seen on the growth of L. sativum. A decrease in enchytraeid and nematode abundance and biomass was, however, observed for the landfill soils as compared to reference soils, implying in situ toxicity to soil-inhabiting organisms. The confirmation of in situ bioavailability and negative effects motivates additional studies of the risk posed to humans of the glassworks villages.

A descriptive study of advising practices during travel health consultations in France.

BACKGROUND: Recommendations for improving traveler adherence address both the content of the advice given and the structure of the consultation. The objective of this article is to describe how travel health consultations are structured in France. METHODS: A questionnaire based on both theoretical foundations and recommendations in the literature was sent to health professionals who practice in travel clinics, all of them members of France's Société de Médecine des Voyages. RESULTS: The response rate was 78.5% (176/224). One hundred thirty nine respondents (78.9%) reported that treatment (vaccinations, in particular) and advising were done at separate times in the consultation. The majority of respondents questioned the traveler on his wishes, difficulties, expectations, experiences, and previous knowledge. A third explored the traveler's perceptions regarding the seriousness of diseases, the effectiveness of prevention measures and the latter's adverse effects with a difference when health professionals were practicing >5 years and/or had received specific training ( P < 0.05). At the end of the consultation, 92% of the respondents asked the traveler whether he understood the advice given. One hundred thirty seven respondents (77.8%) gave travelers a booklet with additional advice, and 66.5% gave them a website where they could find health advice on their destination. Travelers were almost never offered group consultations or the opportunity to work on real-life situations. When there were language barriers, the respondents were more likely to seek help from a French-speaking member of the traveler's entourage (48.9%) than from an interpreter (22.7%). CONCLUSIONS: While the majority of practitioners follow most of the recommendations regarding the structure of travel health consultations, some of the factors that enhance traveler learning are underutilized, reducing the likelihood that travelers will apply the advice given. The study illustrates the need to develop more educational intervention methods and to evaluate their impact on travelers.

Open retromuscular large mesh reconstruction of lumbar incisional hernias including the atrophic muscular area.

PURPOSE: Lumbar incisional hernias (LIH) are a rare wall defect, whose surgical management is challenging because no recommendation exists. Moreover, LIH are frequently associated with flank bulging which should be taken into account during LIH surgical repair. We aimed to describe a cohort of patients operated on for LIH using a homogeneous surgical technique and to report surgical outcomes. METHODS: The records of all consecutive patients operated on in a specialized surgical center between January 2009 and January 2015 were retrospectively reviewed. The same open technique was performed, i.e., using a mesh into the retroperitoneal space posteriorly, placed with the largest overlap inferiorly and posteriorly, and fixed through the controlateral abdominal wall muscles under strong tension to correct the flank bulging. RESULTS: The cohort included 31 patients, of median age 62, who presented two or more comorbidities in 68% of cases. LIH was recurrent in 45% of patients, and was related to nephrectomy in 61% of patients. The mesh was totally extraperitoneal in 65% of patients. The postoperative mortality rate was null. The rate of specific surgical complications was 32.3%, and the rate of overall postoperative morbidity (Clavien-Dindo classification) was 38.7%. After a median follow-up of 27.5 months, the recurrence rate was 6.5% and 9.7% reported chronic pain. CONCLUSION: The open approach for LIH repair was safe and enabled treating flank bulging simultaneously in all patients. Due to the paucity of adequate scientific studies, this reproducible open method could help moving toward a standardization of LIH surgical management.

Predicting the functional states of human iPSC-derived neurons with single-cell RNA-seq and electrophysiology.

Human neural progenitors derived from pluripotent stem cells develop into electrophysiologically active neurons at heterogeneous rates, which can confound disease-relevant discoveries in neurology and psychiatry. By combining patch clamping, morphological and transcriptome analysis on single-human neurons in vitro, we defined a continuum of poor to highly functional electrophysiological states of differentiated neurons. The strong correlations between action potentials, synaptic activity, dendritic complexity and gene expression highlight the importance of methods for isolating functionally comparable neurons for in vitro investigations of brain disorders. Although whole-cell electrophysiology is the gold standard for functional evaluation, it often lacks the scalability required for disease modeling studies. Here, we demonstrate a multimodal machine-learning strategy to identify new molecular features that predict the physiological states of single neurons, independently of the time spent in vitro. As further proof of concept, we selected one of the potential neurophysiological biomarkers identified in this study-GDAP1L1-to isolate highly functional live human neurons in vitro.

Meiofauna distribution in a mangrove forest exposed to shrimp farm effluents (New Caledonia).

Meiofauna abundance, biomass and individual size were studied in mangrove sediments subjected to shrimp farm effluents in New Caledonia. Two strategies were developed: i) meiofauna examination during the active (AP) and the non-active (NAP) periods of the farm in five mangrove stands characteristics of the mangrove zonation along this coastline, ii) meiofauna examination every two months during one year in the stand the closest to the pond (i.e. Avicennia marina). Thirteen taxonomic groups of meiofauna were identified, with nematodes and copepods being the most abundant ones. Meiofauna abundance and biomass increased from the land side to the sea side of the mangrove probably as a result of the increased length of tidal immersion. Abundance of total meiofauna was not significantly different before and after the rearing period. However, the effluent-receiving mangrove presented twice the meiofauna abundance and biomass than the control one. Among rare taxa, mites appeared extremely sensitive to this perturbation.

Trace metal geochemistry in mangrove sediments and their transfer to mangrove plants (New Caledonia).

Because of their physico-chemical inherent properties, mangrove sediments may act as a sink for pollutants coming from catchments. The main objective of this study was to assess the distribution of some trace metals in the tissues of various mangrove plants developing downstream highly weathered ferralsols, taking into account metals partitioning in the sediment. In New Caledonia, mangroves act as a buffer between open-cast mines and the world's largest lagoon. As a result of the erosion of lateritic soils, Ni and Fe concentrations in the sediment were substantially higher than the world average. Whatever the mangrove stand and despite low bioaccumulation and translocations factors, Fe and Ni were also the most abundant metals in the different plant tissues. This low bioaccumulation may be explained by: i) the low availability of metals, which were mainly present in the form of oxides or sulfur minerals, and ii) the root systems acting as barriers towards the transfer of metals to the plant. Conversely, Cu and Zn metals had a greater mobility in the plant, and were characterized by high bioconcentration and translocation factors compared to the other metals. Cu and Zn were also more mobile in the sediment as a result of their association with organic matter. Whatever the metal, a strong decrease of trace metal stock was observed from the landside to the seaside of the mangrove, probably as a result of the increased reactivity of the sediment due to OM enrichment. This reactivity lead to higher dissolution of bearing phases, and thus to the export of dissolved trace metals trough the tidal action. Cu and Zn were the less concerned by the phenomenon probably as a result of higher plant uptake and their restitution to the sediment with litter fall in stands where tidal flushing is limited.

[Symptomatic lumbar incisional hernia after open nephrectomy: What are the risk factors?]. / Éventrations lombaires symptomatiques après néphrectomies par lombotomie: quels sont les facteurs de risque?

OBJECTIVE: Lumbar incisional hernias after open nephrectomy are rare but can lead to aesthetic disorder, discomfort or intestinal obstruction. The aim of the study is to highlight their risk factors. PATIENTS AND METHODS: The characteristics of patients who suffered from symptomatic and surgically treated lumbar incisionnal hernia after open nephrectomy (study group "GE") were compared to those of patients who underwent open nephrectomy without postoperative incisional hernia (control group "GT") using the Student's t test and Mann-Whitney test (statistical significance P value<0.05). GT patients were randomly selected with a 1/4 ratio (1 lumbar incisionnal hernia vs 4 controls). RESULTS: From 2004 to 2014, 417 open nephrectomies were performed in one university hospital. Forty-five patients were included: 9 in GE and 36 in GT. There was no statistically significant difference between GT and GE for weight, height, body mass index (BMI), emergency, partial nephrectomy, laterality, rib resection, laparoscopic conversion to open surgery, postoperative complications, smoking, diabetes mellitus, cardiovascular history, obesity and sex, but there was a statistically significant difference for age, operative time, chronic obstructive pulmonary disease (COPD) and severe obesity (BMI>35) with, respectively, P=0.05, P=0.02, P=0.04 and P=0.02. CONCLUSION: Risk factors for lumbar incisional hernia after open nephrectomy are age, operative time, severe obesity and COPD. LEVEL OF EVIDENCE: 5.

Protein S-nitrosylation in photosynthetic organisms: A comprehensive overview with future perspectives.

BACKGROUND: The free radical nitric oxide (NO) and derivative reactive nitrogen species (RNS) play essential roles in cellular redox regulation mainly through protein S-nitrosylation, a redox post-translational modification in which specific cysteines are converted to nitrosothiols. SCOPE OF VIEW: This review aims to discuss the current state of knowledge, as well as future perspectives, regarding protein S-nitrosylation in photosynthetic organisms. MAJOR CONCLUSIONS: NO, synthesized by plants from different sources (nitrite, arginine), provides directly or indirectly the nitroso moiety of nitrosothiols. Biosynthesis, reactivity and scavenging systems of NO/RNS, determine the NO-based signaling including the rate of protein nitrosylation. Denitrosylation reactions compete with nitrosylation in setting the levels of nitrosylated proteins in vivo. GENERAL SIGNIFICANCE: Based on a combination of proteomic, biochemical and genetic approaches, protein nitrosylation is emerging as a pervasive player in cell signaling networks. Specificity of protein nitrosylation and integration among different post-translational modifications are among the major challenges for future experimental studies in the redox biology field. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.

Peptides derived from the dependence receptor ALK are proapoptotic for ALK-positive tumors.

ALK is a receptor tyrosine kinase with an oncogenic role in various types of human malignancies. Despite constitutive activation of the kinase through gene alterations, such as chromosomal translocation, gene amplification or mutation, treatments with kinase inhibitors invariably lead to the development of resistance. Aiming to develop new tools for ALK targeting, we took advantage of our previous demonstration identifying ALK as a dependence receptor, implying that in the absence of ligand the kinase-inactive ALK triggers or enhances apoptosis. Here, we synthesized peptides mimicking the proapoptotic domain of ALK and investigated their biological effects on tumor cells. We found that an ALK-derived peptide of 36 amino acids (P36) was cytotoxic for ALK-positive anaplastic large-cell lymphoma and neuroblastoma cell lines. In contrast, ALK-negative tumor cells and normal peripheral blood mononuclear cells were insensitive to P36. The cytotoxic effect was due to caspase-dependent apoptosis and required N-myristoylation of the peptide. Two P36-derived shorter peptides as well as a cyclic peptide also induced apoptosis. Surface plasmon resonance and mass spectrometry analysis of P36-interacting proteins from two responsive cell lines, Cost lymphoma and SH-SY5Y neuroblastoma, uncovered partners that could involve p53-dependent signaling and pre-mRNA splicing. Furthermore, siRNA-mediated knockdown of p53 rescued these cells from P36-induced apoptosis. Finally, we observed that a treatment combining P36 with the ALK-specific inhibitor crizotinib resulted in additive cytotoxicity. Therefore, ALK-derived peptides could represent a novel targeted therapy for ALK-positive tumors.

Foraminiferal assemblages as bioindicators to assess potential pollution in mangroves used as a natural biofilter for shrimp farm effluents (New Caledonia).

In New Caledonia, semi-intensive shrimp farms release untreated effluents into the mangrove. Foraminiferal assemblages were analyzed for assessing the impact of effluent release on the benthic compartment. Comparison was made between samples collected (1) in an effluent receiving mangrove before and after the rearing cycle, and (2) for one-year monitoring an effluent receiving and a control mangrove. The distribution of foraminiferal assemblages was primarily driven by the gradient between Rhizophora stands and salt-flats, related to salinity and tidal elevation, and by seasonal cycles. The potential impact of effluent release was due to the combined effects of normal-saline effluents on surface salinity, and of nutrient input and microbial stimulation on food availability. Foraminiferal assemblages did not indicate a substantial impact of farm effluents and suggest that semi-intensive shrimp farming using mangrove for effluent discharge may appear as a sustainable solution in New Caledonia, when considering only the impact on the mangrove itself.

[Is obesity a barrier to kidney transplantation?]. / L'obésité est-elle un frein à la transplantation rénale ?

INTRODUCTION: Kidney transplantation is the most suitable of ESRD care. The proportion of obese people is increasing in the general population and patients with kidney impairment. It is important to assess the impact of obesity on surgical complications of kidney transplantation. The aim of this retrospective study was to signify the correlation between obesity and the occurrence of postoperative urological complications during the first year. METHODS: We conducted a retrospective study from March 1999 to December 2009. We conducted a chart review of patients undergoing kidney transplantation. The kidneys were taken from cadaveric donors. Data collected included age, weight, height, preoperative BMI; causal nephropathy, smoking, hypertension, diabetes, anticoagulation therapy. Intraoperative data included operative time (DO), cold ischemia. Urological complications were recorded during the first year after the kidney transplantation (vascular anastomotic strictures, ureterovesical stenosis, lymphorrheas, pyelonephritis, hematoma, wound infection). Statistical analysis consisted of a t-test for independent samples and univariate and multivariate logistic regression for the occurrence of complications. RESULTS: Four hundred and twenty-two patients were transplanted in total. We excluded 20 patients. BMI and duration of surgery patients with complications were significantly different from those of patients with no complications (P=0.016 and P=0.039, respectively). Obese (n=48) had more diabetes (12.5% versus 3.7%, P=0.014), were more often smoking (35.4% versus 22%, P=0.012), had a longer DO (203.64minutes versus 182.46minutes, P=0.006), and complications (62.5% versus 50.28%, P=0.03) than patients with a BMI <30 (n=354). After adjusting for age, smoking, DO, diabetes and BMI showed that only BMI was an independent predictor of the occurrence of postoperative complications with P=0.048 and RR=1.058 [CI: 1 to 1.119]. However, there was no more transplantectomy obese (P=0.911). CONCLUSION: Our study showed that there is a significant risk of surgical complications after kidney transplantation in obese patients. But ultimately, this does not affect graft survival because there are no more transplantectomies or return to dialysis. LEVEL OF EVIDENCE: 5.

Study of the impacts of patient-educators on the course of basic sciences in dental studies.

Ever since 2006, Nantes University dental educators have started organising lectures led by the mother of a young patient suffering from ectodermic dysplasia (patient-educator) to help second-year students to better understand how important it is for their future dental work to better understand basic sciences. In this study, we have analysed this training experience on students' motivation. For this purpose, students were asked to complete questionnaires 10 days after the patient-educator's lecture (early assessment; n = 193) and 4 years later, during the last year of their dental studies (delayed assessment; n = 47). Moreover, 3 years after the first lecture, we analysed the ability of students to diagnose a mother carrying the ectodermic dysplasia genetic disorder, using a case-based learning exercise with a patient showing dental features similar to those exposed by the patient-educator (measure of knowledge; n = 42). Ten days after the lecture, the early assessment shows that all the students were interested in the lecture and 59% of the students declared being motivated to find out more about genetics whilst 54% declared the same thing about embryology courses. Moreover, 4 years later, 67% of the students remembered the patient-educator's lecture a little or very well. Three years after the course, 83% of the students diagnosed ectodermal dysplasia whilst studying the case-based example that listed typical dental phenotypes. In conclusion, this study shows that this original educational approach enhances dental students' motivation in learning basic sciences and that patient-educators could offer many benefits for students and patients.

[The impact of obesity on renal function at one year after kidney transplantation: single-center experience]. / Impact de l'obésité sur la fonction rénale à 1 an chez les transplantés rénaux: expérience mono centrique.

INTRODUCTION: Kidney transplantation is the treatment of choice for ESRD. Several studies have investigated the factors that may affect kidney function at 1 year. The factors mentioned are anemia, hypercholesterolemia, immunosuppressors, etc. We studied the independent predictors of serum creatinine>100µmol/L at 1 year. MATERIALS AND METHODS: We conducted a retrospective study from March 1999 to December 2009. We conducted a chart review of 402 kidney transplant patients. The kidneys were removed from cadaveric donors. Data collected included age, weight, height, preoperative BMI, the causal nephropathy, smoking, hypertension, diabetes, anticoagulation. Intraoperative data included operative time, and cold ischemia. Statistical analysis consisted of a t-test for independent samples comparing the group with a creatinine≤100µmol/L vs>100 group, and univariate and multivariate Cox regression for a serum creatinine>100µmol/L at 1 year and test of correlation between BMI and serum creatinine at 1 year postoperatively. RESULTS: We found a significant difference in BMI and cold ischemia with P=0.008 and P=0.002, respectively. In contrast there was no difference in age, operative time and blood loss, P=0.758, P=0.941 and P=0.963, respectively. Multivariate Cox regression showed that donor age P=0.004 (HR: 1.016 and CI: 1.005-1.027), a recipient age P=0.023 (HR: 0.986 and CI: 0.974-0.998) and BMI P=0.001 (HR: 1.019 and CI: 1.010-1.028) were independent predictors of serum creatinine>100µmol/L at 1 year. The Pearson correlation coefficient r=0.154 (P=0.004) showed a significant correlation between BMI and serum creatinine. CONCLUSION: Our study showed that donor age, recipient age and BMI were independent predictors of renal function>100µmol/L at 1 year. Our results highlight the difficulty of the management of obesity in renal transplant patients. LEVEL OF EVIDENCE: 5.

[Perceptions of cystic fibrosis patients, patient relatives and physicians: barriers or motivations to lung transplantation]. / Motivations et freins à la greffe chez patients, aidants et médecins dans la mucoviscidose.

INTRODUCTION: The aims of this study are to describe qualitatively the perceptions of three groups involved in the cystic fibrosis transplant decision, looking for similarities and differences between groups, and to identify those that act as motivations or barriers to transplantation. METHODS: Thirty patients, 26 patient relatives and 27 physicians were interviewed, and concept maps were constructed from those interviews. Their degree of transplant acceptance at the time of the interview was measured. RESULTS: There were motivations and barriers in the pre-, peri- and post-transplant period. Analysis revealed similar perceptions regarding the risks and benefits of transplantation, but also different perceptions in the specific concerns of each group. Patients and patient relatives expressed many questions and fears in their concept maps, and physicians expressed difficulties. CONCLUSIONS: This study highlights the value of better understanding the perceptions of patients, relatives and physicians, in order to remove some of the barriers to transplantation. It also demonstrates the benefits of education and support activities for patients and patient relatives prior to transplantation, and continuing education and supervision for physicians.

Influence of experimental conditions on data variability in the liver comet assay.

The in vivo comet assay has increasingly been used for regulatory genotoxicity testing in recent years. While it has been demonstrated that the experimental execution of the assay, for example, electrophoresis or scoring, can have a strong impact on the results; little is known on how initial steps, that is, from tissue sampling during necropsy up to slide preparation, can influence the comet assay results. Therefore, we investigated which of the multitude of steps in processing the liver for the comet assay are most critical. All together eight parameters were assessed by using liver samples of untreated animals. In addition, two of those parameters (temperature and storage time of liver before embedding into agarose) were further investigated in animals given a single oral dose of ethyl methanesulfonate at dose levels of 50, 100, and 200 mg/kg, 3 hr prior to necropsy. The results showed that sample cooling emerged as the predominant influence factor, whereas variations in other elements of the procedure (e.g., size of the liver piece sampled, time needed to process the liver tissue post-mortem, agarose temperature, or time of lysis) seem to be of little relevance. Storing of liver samples of up to 6 hr under cooled conditions did not cause an increase in tail intensity. In contrast, storing the tissue at room temperature, resulted in a considerable time-dependent increase in comet parameters.

Poor long-term stability of the Corvita abdominal stentgraft.

INTRODUCTION: The endovascular treatment of abdominal aortic aneurysms was introduced in the early 1990s, with different generations of devices using various options for either the stent skeleton or the membrane. REPORT: Corvita generated one of these devices using braided stainless steel and a porous spun polycarbonate urethane membrane. DISCUSSION: In this report, we describe a case involving Corvita stentgraft explantation for complete aneurysm reperfusion after 13 years, demonstrating major degradation of the polyurethane membrane.