Green Additives in Chitosan-Based Bioplastic Films: Physical, Mechanical, and Chemical Properties.

To switch to alternatives for fossil-fuel-based polymer materials, renewable raw materials from green resources should be utilized. Chitosan is such a material that is a strong, but workable derivative from chitin, obtained from crustaceans. However, various applications ask for specific plastic properties, such as certain flexibility, hardness and transparency. With different additives, also obtainable from green resources, chitosan-based composites in the form of self-supporting films, ranging from very hard and brittle to soft and flexible were successfully produced. The additives turned out to belong to one of three categories, namely linear, non-linear, or crosslinking additives. The non-linear additives could only be taken up to a certain relative amount, whereas the uptake of linear additives was not limited within the range of our experiments. Additives with multiple functional groups tend to crosslink chitosan even at room temperature in an acidic medium. Finally, it was shown that dissolving the chitosan in acetic acid and subsequently drying the matrix as a film results in reacetylation compared to the starting chitosan source, resulting in a harder material. With these findings, it is possible to tune the properties of chitosan-based polymer materials, making a big step towards application of this renewable polymer within consumer goods.

Targeted mupirocin-based decolonization for Staphylococcus aureus carriers and the subsequent risk of mupirocin resistance in haemodialysis patients - a longitudinal study over 20 years.

Mupirocin-based decolonization of Staphylococcus aureus carriers undergoing haemodialysis is not widely implemented due to concerns of mupirocin resistance. In our haemodialysis unit, a strategy combining universal S. aureus screening with targeted mupirocin-based decolonization was introduced two decades ago. In this study of haemodialysis patients, mupirocin resistance was assessed in blood and colonizing S. aureus isolates during two periods. Mupirocin resistance in S. aureus was infrequent in both blood and colonizing isolates. Furthermore, in the years 2003-2021, a decreasing trend in the annual rate of S. aureus bloodstream infections was observed. Targeted mupirocin-based decolonization of S. aureus carriers undergoing haemodialysis is a sustainable measure for preventing healthcare-associated infections.

Does plastic waste kill mangroves? A field experiment to assess the impact of macro plastics on mangrove growth, stress response and survival.

The value of mangroves has been widely acknowledged, but mangrove forests continue to decline due to numerous anthropogenic stressors. The impact of plastic waste is however poorly known, even though the amount of plastic litter is the largest in the region where mangroves are declining the fastest: South East Asia. In this study, we examine the extent of the plastic waste problem in mangroves along the north coast of Java, Indonesia. First, we investigate how much of the forest floor is covered by plastic in the field (in number of items per m2 and in percentage of the forest floor covered by plastic), and if plastic is also buried in the upper layers of the sediment. We then experimentally investigate the effects of a range of plastic cover percentages (0%, 50% and 100%) on root growth, stress response of the tree and tree survival over a period of six weeks. Field monitoring showed that plastic was abundant, with 27 plastic items per m2 on average, covering up to 50% of the forest floor at multiple locations. Moreover, core data revealed that plastic was frequently buried in the upper layers of the sediment where it becomes immobile and can create prolonged anoxic conditions. Our experiment subsequently revealed that prolonged suffocation by plastic caused immediate pneumatophore growth and potential leaf loss. However, trees in the 50%-plastic cover treatment proved surprisingly resilient and were able to maintain their canopy over the course of the experiment, whereas trees in the 100%-plastic cover treatment had a significantly decreased leaf area index and survival by the end of the experiment. Our findings demonstrate that mangrove trees are relatively resilient to partial burial by plastic waste. However, mangrove stands are likely to deteriorate eventually if plastic continues to accumulate.

Congenital lung abnormality quantification by computed tomography: The CLAQ method.

INTRODUCTION: To date, no consensus has been reached on the optimal management of congenital lung abnormalities, and factors predicting postnatal outcome have not been identified. We developed an objective quantitative computed tomography (CT) scoring method, and assessed its value for clinical decision-making. METHODS: Volumetric CT-scans of all patients born with a congenital lung abnormality between January 1999 and 2018 were assessed. Lung disease was quantified using the newly-developed congenital lung abnormality quantification (CLAQ) scoring method. In 20 equidistant axial slices, cells of a square grid were scored according to the abnormality within. The scored CT parameters were used to predict development of symptoms, and SD scores for spirometry and exercise tolerance (Bruce treadmill test) at 8 years of age. RESULTS: CT-scans of 124 patients with a median age of 5 months were scored. Clinical diagnoses included congenital pulmonary airway malformation (49%), bronchopulmonary sequestration (27%), congenital lobar overinflation (22%), and bronchogenic cyst (1%). Forty-four patients (35%) developed symptoms requiring surgery of whom 28 (22%) patients became symptomatic before a CT-scan was scheduled. Lesional hyperdensity was found as an important predictor of symptom development and decreased exercise tolerance. Using receiver operating characteristic analysis, an optimal cut-off value for developing symptoms was found at 18% total disease. CONCLUSION: CT-quantification of congenital lung abnormalities using the CLAQ method is an objective and reproducible system to describe congenital lung abnormalities on chest CT. The risk for developing symptoms may increase when more than a single lung lobe is affected.

[Direct discharge from the ED for patients with simple stable injuries: a Dutch pilot study]. / Direct ontslag vanaf de SEH voor patiënten met simpele en stabiele letsels.

OBJECTIVE: To describe and study (a) the implementation of direct discharge from a Dutch Emergency Department (ED) for patients with relatively simple stable injuries (SSIs), (b) preliminary logistical and financial effects, and (c) patients' experiences. DESIGN: Prospective cohort study. METHOD: Following the example of a healthcare reorganisation in the United Kingdom, in May 2019 we changed the treatment protocols of eleven SSIs. Since that time, no standard follow-up appointment has been scheduled for these patients. Patients are given information about treatment and the recovery period, and a form of immobilization is applied which can easily be removed at home. This information is summarised in a discharge leaflet and a smartphone application. A telephone helpline is available for any concerns or questions. During the implementation phase we determined compliance with, and deviation from, the protocol daily for 3 months. To determine the logistical and financial effects we compared the healthcare utilization of all patients with SSIs three months before and after implementation. Patient satisfaction and the shift in treatment towards primary care were determined by means of questionnaires. RESULTS: In the three months before implementation 275 patients with an SSI presented to our ED, compared with 318 in the same period after implementation; 304 of the 318 patients were directly discharged (protocol compliance 95.6%). We found a significant reduction in follow-up appointments (-91%), radiological imaging (-72%), and costs. Patient satisfaction was comparable. There was no shift towards primary care in healthcare utilisation. CONCLUSION: In the Netherlands, direct discharge from the ED seems to be an effective and safe alternative to traditional treatment with outpatient follow-up. Further studies on patient-reported outcomes should determine if this process is in concordance with the principle of Value Based Health Care.

Diagnostic properties of the SPIQuestionnaire to detect Posterior Circumflex Humeral Artery Disease in elite volleyball players: a cross-sectional study.

OBJECTIVES: Sports related aneurysmal degeneration and thrombosis of the Posterior Circumflex Humeral Artery (PCHA) has been known to cause symptoms of digital ischemia (DI) in elite volleyball players. Studies have reported symptoms of DI in as much as 28% of the elite indoor volleyball players. The purpose of this study was to determine the diagnostic value of the Shoulder PCHA Pathology and digital Ischemia - Questionnaire (SPI-Q) for detection of sports related PCHA disease using ultrasound data as the standard of reference. METHODS: The SPI-Q was completed by elite indoor volleyball players from the highest and single highest Dutch volleyball division and by elite beach volleyball players participating in the 2014 Grand Slam Beach Tournament The Hague (GSBTH). Ultrasound assessment of the dominant shoulder was performed on-site using the SPI-US protocol. The SPI-Q sensitivity, specificity, positive - and negative predictive value and positive - and negative likelihood ratios, and the diagnostic odds ratio were calculated for detection of sports related PCHA disease, using ultrasound as the standard of reference. RESULTS: Two hundred twenty-four elite male indoor volleyball players from the Dutch division were included in this study and 62 elite male and female beach volleyball players participating in the GSBTH: a total of 278 players. Thirty-five percent of the players reported symptoms of DI. The prevalence of PCHA disease was 6.1%. For the SPI-Q we found a sensitivity of 18% (95% CI 4-43), specificity of 64% (95% CI 58-70), positive predictive value of 3% (95% CI 0.7-8.9) and negative predictive value of 92% (95% CI 87-96), positive likelihood ratio of 0.50 (95% CI 0.18-1.40), negative likelihood ratio of 1.28 (95% CI 1.01-1.62) and a diagnostic odds ratio of 0.39 (95% CI 0.11-1.38). CONCLUSION: The diagnostic value of the SPI-Q to detect PCHA disease in elite volleyball players is poor, which makes it unsuitable as a diagnostic instrument for sports related PCHA disease specifically. However, it can be used to assess all-cause symptoms of DI and raise awareness within athletes and sports physicians, which is important for preventing ischemic complications.

QRS Fragmentation and QTc Duration Relate to Malignant Ventricular Tachyarrhythmias and Sudden Cardiac Death in Patients with Hypertrophic Cardiomyopathy.

BACKGROUND: QRS fragmentation (fQRS) and prolonged QTc interval on surface ECG are prognostic in various cardiomyopathies other than hypertrophic cardiomyopathy (HCM). The association between fQRS and prolonged QTc duration with occurrence of ventricular tachyarrhythmias or sudden cardiac death (VTA/SCD) in patients with HCM was explored. METHODS AND RESULTS: One hundred and ninety-five clinical HCM patients were studied. QTc duration was derived applying Bazett's formula; fQRS was defined as presence of various RSR' patterns, R or S notching and/or >1 additional R wave in any non-aVR lead in patients without pacing or (in)complete bundle branch block. The endpoints comprised SCD, ECG documented sustained VTA (tachycardia or fibrillation) or appropriate implantable cardioverter defibrillator (ICD) therapies (antitachycardia pacing [ATP] or shock) for VTA in ICD recipients (n = 58 [30%]). QT prolonging drugs recipients were excluded. After a median follow-up of 5.7 years (IQR 2.7-9.1), 26 (13%) patients experienced VTA or SCD. Patients with fQRS in ≥3 territories (inferior, lateral, septal, and/or anterior) (p = 0.004) or QTc ≥460 ms (p = 0.009) had worse cumulative survival free of VTA/SCD than patients with fQRS in <3 territories or QTc <460 ms. fQRS in ≥3 territories (ß 4.5, p = 0.020, 95%CI 1.41-14.1) and QTc ≥460 ms (ß 2.7, p = 0.037, 95%CI 1.12-6.33) were independently associated with VTA/SCD. Likelihood ratio test indicated assessment of fQRS and QTc on top of conventional SCD risk factors provides incremental predictive value for VTA/SCD (p = 0.035). CONCLUSIONS: Both fQRS in ≥3 territories and QTc duration are associated with VTA/SCD in HCM patients, independently of and incremental to conventional SCD risk factors.

Candidate chemosensory ionotropic receptors in a Lepidoptera.

A new family of candidate chemosensory ionotropic receptors (IRs) related to ionotropic glutamate receptors (iGluRs) was recently discovered in Drosophila melanogaster. Through Blast analyses of an expressed sequenced tag library prepared from male antennae of the noctuid moth Spodoptera littoralis, we identified 12 unigenes encoding proteins related to D. melanogaster and Bombyx mori IRs. Their full length sequences were obtained and the analyses of their expression patterns suggest that they were exclusively expressed or clearly enriched in chemosensory organs. The deduced protein sequences were more similar to B. mori and D. melanogaster IRs than to iGluRs and showed considerable variations in the predicted ligand-binding domains; none have the three glutamate-interacting residues found in iGluRs, suggesting different binding specificities. Our data suggest that we identified members of the insect IR chemosensory receptor family in S. littoralis and we report here the first demonstration of IR expression in Lepidoptera.

Spread of infectious chronic bee paralysis virus by honeybee (Apis mellifera L.) feces.

Knowledge of the spreading mechanism of honeybee pathogens within the hive is crucial to our understanding of bee disease dynamics. The aim of this study was to assess the presence of infectious chronic bee paralysis virus (CBPV) in bee excreta and evaluate its possible role as an indirect route of infection. Samples of paralyzed bees were (i) produced by experimental inoculation with purified virus and (ii) collected from hives exhibiting chronic paralysis. CBPV in bee heads or feces (crude or absorbed onto paper) was detected by reverse transcription-PCR. CBPV infectivity was assessed by intrathoracic inoculation of bees with virus extracted from feces and by placement of naive bees in cages previously occupied by contaminated individuals. CBPV RNA was systematically detected in the feces of naturally and experimentally infected bees and on the paper sheets that had been used to cover the floors of units containing bees artificially infected with CBPV or the floor of one naturally infected colony. Both intrathoracic inoculation of bees with virus extracted from feces and placement of bees in contaminated cages provoked overt disease in naive bees, thereby proving that the excreted virus was infectious and that this indirect route of infection could lead to overt chronic paralysis. This is the first experimental confirmation that infectious CBPV particles excreted in the feces of infected bees can infect naive bees and provoke overt disease by mere confinement of naive bees in a soiled environment.

In vitro culture of large bone substitutes in a new bioreactor: importance of the flow direction.

New biomaterials combined with osteogenic cells are now being developed as an alternative to autogeneous bone grafts when the skeletal defect reaches a critical size. Yet, the size issue appears to be a key obstacle in the development of bone tissue engineering. Bioreactors are needed to allow the in vitro expansion of cells inside large bulk materials under appropriate conditions. However, no bioreactor has yet been designed for large-scale 3D structures and custom-made scaffolds. In this study, we evaluate the efficiency of a new bioreactor for the in vitro development of large bone substitutes, ensuring the perfusion of large ceramic scaffolds by the nutritive medium. The survival and proliferation of cells inside the scaffolds after 7 and 28 days in this dynamic culture system and the impact of the direction of the flow circulation are evaluated. The follow-up of glucose consumption, DNA quantification and microscopic evaluation all confirmed cell survival and proliferation for a sample under dynamic culture conditions, whereas static culture leads to the death of cells inside the scaffolds. Two directions of flow perfusion were assayed; the convergent direction leads to enhanced results compared to divergent flow.

Interactions of B16F10 melanoma cells aggregated on a cellulose substrate.

There is evidence that the shape of cells and their contact with a matrix direct the growth and the differentiation of both normal and cancer cells. Cells in 3D culture resemble the in vivo situation more closely than do those in conventional 2D cultures. We have studied the interactions and functions of B16F10 mouse melanoma cells, which spread and grow well on tissue culture polystyrene (tPS), when they were made to aggregate on cellulose-coated Petri dishes (CEL). This aggregation of melanoma cells on CEL was Ca2+ dependent and mediated by N-cadherins. The levels of N-cadherin and beta-catenin transcripts in cells cultured on CEL and tPS were similar, but those on CEL contained less beta-catenin protein. Immunoprecipitation and immunostaining showed that both N-cadherins and beta-catenins were present at the membranes of cells on CEL. Cells proliferated significantly more slowly after 48 h on CEL and the cellulose coating caused most of them to arrest in G1. We also compared the melanin contents and tyrosinase activity of cells on CEL and controls grown on tPS. Melanogenesis was induced in cells aggregated on CEL. A cellulose substrate thus appears to be an outstanding tool for studying cell-cell interactions and cell functions in 3D cultures.

[Taxonomy of Apis mellifera viruses]. / Les virus infectant l'abeille Apis mellifera : le point sur leur classification.

With the exception of the filamentous virus, all viruses of the honey bee (Apis mellifera L.) are single stranded RNA viruses. At the time of their discovery, they have been classified as picorna-like viruses. Progress in molecular biology allowed sequencing some of them and revealed they were differed from picornaviruses. Two new taxons were therefore created: the Iflavirus genus and the Dicistroviridae family, which includes the genus Cripavirus, the unique genus of this family. These viruses differ from the picornaviruses at the genomic level by the order of genes and, in the case of dicistrovirus, by the organization of these genes in two ORF, each having their own regulation system. The phylogenetic analysis of members of both taxons generally shown only few similarities at the nucleotide and amino-acid level. However, within each taxon, some viruses show strong similarities, reflecting a probable common origin. Geographical isolates of the same viruses showgenetic and protein variability, which are new illustrations of the potential evolution of RNA viruses.

[Acute schizophrenia concept and definition: investigation of a French psychiatrist population]. / Définition de l'etat aigu dans la schizophrénie: enquête réalisée auprès des psychiatres français.

For schizophrenic disorders, the clinical conception of "acute state" is widely used in clinical settings to assess the effectiveness of therapeutic programs as well as epidemiological studies. Schizophrenic-specific symptomatology modification, need for hospitalization, significant change in care, disturbances in social behavior or suicide attempts were all used to define acute schizophrenic state. The decision to hospitalize is frequently used to define acute state but refers to multiple factors such as mood disorder, suicide attempts, drug abuse or social and environmental problems. Indeed, several and distinct definitions in a criteria basis form are available but no one has reached consensus. Because recognition of acute schizophrenic state remains based on the subjective clinician's advice, epidemiological and therapeutic studies fail in validity and reliability. The aim of the study was to evaluate how a population of French psychiatrists define criteria and therapeutic targets of acute schizophrenic state in their clinical practice. Psychiatrists filled out a self administered interview. At the time the interview was given, clinicians were notified that they were participating in a clinical consensus survey about schizophrenia. Six major indicators for acute state definition based on the literature data were proposed: general schizophrenic symptomatology modification (depression, anxiety, agitation, impulsivity/aggressiveness), specific schizophrenic symptomatology modification (positive symptoms, negative symptoms, disorganization), need for hospitalization, significant change in care, disturbance in social behavior and lastly, suicidal behavior. Minimal duration (1.2 or 4 weeks) of general and specific schizophrenic symptomatology modification required to define acute state were evaluated. The booklet included the 30 PANSS symptoms listed with their definitions. Among this symptom list, clinicians were instructed to select the ten criteria which they estimated best defined the acute state, followed by the ten most important target symptoms to be treated. Out of 2,369 questionnaires, 1,584 were collected on time (66.9%). Among the six majors indicators proposed to define acute state 75% of psychiatrists considered 1 to 3 criteria. Three were more frequently rated, including core schizophrenic symptomatology disturbance (68.4%), general schizophrenic symptomatology disturbance (68.0%) and suicidal behavior (64.9%). The other criteria were rated as follows: need for hospitalization (26.8%), significant change in care (18.3%), and disturbance in social behavior (29.1%). For 53.2% of psychiatrists the definition of acute state requires the presence of specific schizophrenic symptomatology for a minimal duration of one week. Two weeks with general symptomatology was required for 45.5% of psychiatrists to define acute state. Symptoms more often rated within the four first choices for acute state definition included delusions, conceptual disorganization, hallucinatory behavior and excitement. Except for grandiosity, all the PANSS positive subscale items were chosen to be included in the definition (delusions, conceptual disorganization, hallucinatory behavior, excitement, suspiciousness/persecution and hostility). Four items, including anxiety, depression, uncontrolled hostility, inner tension from the general psychopathology subscale were chosen as part of the ten most important criteria to define acute state. On the PANSS negative subscale (blunted affect, emotional withdrawal, poor relationships, passive apathetic withdrawal, difficulty in abstract thinking, lack of spontaneity/flow of conversation and stereotyped thinking), no item was rated to be included in the acute state definition. The highest rated symptoms among the four first choices for treatment included delusions, hallucinatory behavior, excitement and anxiety. The ten most important criteria for treatment were the same as for acute state definition with differences in frequency. Excited state, depression and suspiciousness/persecution were more rated for treatment than definition whereas delusion, hostility and conceptual disorganization were less rated as treatment target than definition criteria. In clinical practice, recognition of acute schizophrenic state is underscored by the association of specific schizophrenic symptomatology (positive symptoms, negative symptoms, disorganization) and general symptomatology (impulsivity/aggressiveness, anxiety, depression, agitation) of schizophrenia. For most clinicians, acute state definition requires specific symptom for a minimum of one week and other non-specific indicators such as suicidal behaviour have to be taken into account. With regard to PANSS criteria, most positive schizophrenic symptoms and some general schizophrenic symptoms are necessary for definition and designated as treatment priorities. Negative symptoms were not taken into account. Hallucinatory behavior is the first symptom rated in definition and is considered by psychiatrists as the absolute therapeutic priority. This survey could be a first step in the construction of an operational and consensual definition. This definition is strongly needed as a valid measurement in therapeutic and epidemiological outcome studies, which remain at least partly based on clinician subjective judgment.

Comparative particle-induced cytotoxicity toward macrophages and fibroblasts.

The cytotoxicity caused by the debris resulting from wear of prostheses can produce major damage to tissues around the implant. We have compared particle internalization by macrophages and fibroblasts in vitro and analyzed cell death. J774.2 macrophages and L929 fibroblasts were incubated with 0.43 and 2.81 microm alumina particles or 0.45 and 3.53 microm polystyrene (PS) beads. Incubation of J774.2 cells with alumina particles of both sizes and 0.5 and 1.0 mg/ml PS beads significantly decreased cell numbers in a particle concentration-dependent manner. L929 cells were not affected by lower concentrations of 0.43 microm alumina particles (which aggregate at high concentrations) and they internalized 0.45 microm PS beads without any decrease in cell numbers. Particles were more cytotoxic for macrophages than for fibroblasts. Particles caused the size of both types of cells to increase in correlation with cytotoxicity. Trypan blue exclusion and lactate dehydrogenase release showed cell membrane leakage for both types of cells incubated with PS beads for 24 h. Apoptosis was assessed by annexin V-FITC, propidium iodide staining and assay of caspase 3 activity. Macrophage death appeared to depend on both necrosis, caused mainly by 3.53 microm PS beads, and apoptosis, mainly due to 0.45 microm PS beads. The release of the inflammatory cytokine IL-6 appears to be nonlinearly correlated with cytotoxicity. Thus, the size of the internalized particles affects macrophages and fibroblasts differently, and the increase in cell size can be used as a preliminary criterion of particle cytotoxicity in vitro.

Phosphorylcholine-containing N-glycans of Trichinella spiralis: identification of multiantennary lacdiNAc structures.

Although the presence of phosphorylcholine (PC) in Trichinella spiralis is well established, the precise structure of the PC-bearing molecules is not known. In this paper, we report structural studies of N-glycans released from T.spiralis affinity-purified antigens by peptide N-glycosidase F. Three classes of N-glycan structures were observed: high mannose type structures; those which had been fully trimmed to the trimannosyl core and were sub-stoichiometrically fucosylated; and those with a trimannosyl core, with and without core fucosylation, carrying between one and eight N-acetylhexosamine residues. Of the three classes of glycans, only the last was found to be substituted with detectable levels of phosphorylcholine.

[Sweet syndrome in an infant]. / Syndrome de Sweet chez un nourrisson.

BACKGROUND: Acute febrile neutrophilic dermatosis (Sweet's syndrome) is very uncommon in infancy. Systemic corticosteroid treatment is the standard therapy, usually leading to dramatic improvement within a few days. CASE REPORT: A seven-month-old female infant was admitted for investigation of a rash developing over ten days with fever. Physical examination and skin biopsy led to a diagnosis of Sweet's syndrome. The relative inefficiency of systemic corticotherapy induced the parents to stop all treatment. CONCLUSION: This case report allows us: 1) to consider the clinical and biological features of Sweet's syndrome in infancy; 2) to describe a corticosteroid resistant disease; and 3) to observe the course of a spontaneous evolution of Sweet's syndrome.