Unmodified multi-wall carbon nanotubes in polylactic acid for electrically conductive injection-moulded composites

Tailoring the properties of natural polymers such as electrical conductivity is vital to widen the range of future applications. In this article, the potential of electrically conducting multi-wall carbon nanotube (MWCNT)/polylactic acid (PLA) composites produced by industrially viable melt mixing is assessed simultaneously to MWCNT influence on the composite’s mechanical strength and polymer crystallinity. Atomic force microscopy observations showed that melt mixing achieved an effective distribution and individualization of unmodified nanotubes within the polymer matrix. However, as a trade-off of the poor tube/matrix adhesion, the tensile strength was lowered. With 10 wt% MWCNT loading, the tensile strength was 26% lower than for neat PLA. Differential scanning calorimetric measurements indicated that polymer crystallization after injection moulding was nearly unaffected by the presence of nanotubes and remained at 15%. The resulting composites became conductive below 5 wt% loading and reached conductivities of 51 S m−1 at 10 wt%, which is comparable with conductivities reported for similar nanocomposites obtained at lab scale. </jats:p

Surgery Due to Inflammatory Bowel Disease During Pregnancy : Mothers and Offspring Outcomes From an Ecco Confer Multicentre Case Series (Scar Study)

i) To evaluate the evolution of pregnancies and offspring after inflammatory bowel disease (IBD) surgery during pregnancy; and ii) to describe the indications, the surgical techniques, and the frequency of caesarean section concomitant to surgery.Patients operated on due to IBD during pregnancy after 1998 were included. Participating clinicians were asked to review their databases to identify cases. Data on patients' demographics, IBD characteristics, medical treatments, IBD activity, pregnancy outcomes, surgery, delivery, foetal and maternal outcomes, were recorded.Forty-four IBD patients were included, 75% had Crohn's disease. Eighteen percent of the surgeries were performed in the 1 st trimester, 55% in the 2 nd, and 27% in the 3 rd trimester. One patient had complications during surgery, and 27% had postsurgical complications. No patient died. Seventy percent of deliveries were carried out by caesarean section. There were 40 newborns alive and 4 miscarriages/stillbirths (1 in the 1 st, 2 in the 2 nd, and 1 in the 3 rd trimester): 2 occurred during surgery, and another 2 occurred 2 weeks after surgery. Fourteen percent of the surgeries during the 2 nd trimester and 64% of those in the 3 rd trimester ended up with a simultaneous cesarean section or vaginal delivery. Of the 40 newborns, 61% were premature, and 47% had low birth weight; 42% of newborns needed hospitalisation (25% in the intensive care unit).IBD surgery during pregnancy remains an extremely serious situation. Therefore, surgical management should be performed in a multidisciplinary team, involving gastroenterologists, colorectal surgeons, obstetricians and neonatal specialists

Intriguing Relationships Between Cancer and Systemic Sclerosis: Role of the Immune System and Other Contributors

Systemic sclerosis (SSc) is an autoimmune connective tissue disorder, characterized by multisystem involvement, vasculopathy, and fibrosis. An increased risk of malignancy is observed in SSc (including breast and lung cancers), and in a subgroup of patients with specific autoantibodies (i.e., anti-RNA polymerase III and related autoantibodies), SSc could be a paraneoplastic syndrome and might be directly related to an immune response against cancer. Herein, we reviewed the literature, focusing on the most recent articles, and shed light onto the potential relationship between cancer and scleroderma regarding temporal and immunological dimensions

Multisystem inflammatory syndrome in children in western countries: decreasing incidence as the pandemic progresses? An observational multicenter international cross-sectional study

Multisystemic inflammatory syndrome temporally associated with SARS-CoV-2 infection in children (MIS-C) has been reported worldwide.1–7 The case definition of MIS-C has been estab- lished by different institutions and organizations such as the US Centers for Disease Control and Prevention (CDC) (May 14, 2020),8 the Royal College of Paediatrics and Child Health in the United Kingdom (RCPCH) (May 1, 2020)9,10 and the World Health Organi- zation (WHO) (May 15, 2020).1Postprint (published version

Streptococcus pyogenes Cas9 ribonucleoprotein delivery for efficient, rapid and marker-free gene editing in Trypanosoma and Leishmania

Kinetoplastids are unicellular eukaryotic flagellated parasites found in a wide range of hosts within the animal and plant kingdoms. They are known to be responsible in humans for African sleeping sickness ( Trypanosoma brucei ), Chagas disease ( Trypanosoma cruzi ), and various forms of leishmaniasis ( Leishmania spp.), as well as several animal diseases with important economic impact (African trypanosomes, including T. congolense ). Understanding the biology of these parasites necessarily implies the ability to manipulate their genomes. In this study, we demonstrate that transfection of a ribonucleoprotein complex, composed of recombinant Streptococcus pyogenes Cas9 ( Sp Cas9) and an in vitro -synthesized guide RNA, results in rapid and efficient genetic modifications of trypanosomatids, in marker-free conditions. This approach was successfully developed to inactivate, delete and mutate candidate genes in various stages of the life cycle of T. brucei and T. congolense , and Leishmania promastigotes. The functionality of Sp Cas9 in these parasites now provides, to the research community working on these parasites, a rapid and efficient method of genome editing, without requiring plasmid construction and selection by antibiotics. Importantly, this approach is adaptable to any wild-type parasite, including field isolates

PLoS Biol

Microorganisms must make the right choice for nutrient consumption to adapt to their changing environment. As a consequence, bacteria and yeasts have developed regulatory mechanisms involving nutrient sensing and signaling, known as "catabolite repression," allowing redirection of cell metabolism to maximize the consumption of an energy-efficient carbon source. Here, we report a new mechanism named "metabolic contest" for regulating the use of carbon sources without nutrient sensing and signaling. Trypanosoma brucei is a unicellular eukaryote transmitted by tsetse flies and causing human African trypanosomiasis, or sleeping sickness. We showed that, in contrast to most microorganisms, the insect stages of this parasite developed a preference for glycerol over glucose, with glucose consumption beginning after the depletion of glycerol present in the medium. This "metabolic contest" depends on the combination of 3 conditions: (i) the sequestration of both metabolic pathways in the same subcellular compartment, here in the peroxisomal-related organelles named glycosomes; (ii) the competition for the same substrate, here ATP, with the first enzymatic step of the glycerol and glucose metabolic pathways both being ATP-dependent (glycerol kinase and hexokinase, respectively); and (iii) an unbalanced activity between the competing enzymes, here the glycerol kinase activity being approximately 80-fold higher than the hexokinase activity. As predicted by our model, an approximately 50-fold down-regulation of the GK expression abolished the preference for glycerol over glucose, with glucose and glycerol being metabolized concomitantly. In theory, a metabolic contest could be found in any organism provided that the 3 conditions listed above are met

Management of Postoperative Crohn's Disease: Missing Pieces of the Puzzle

status: publishe

Solid-State Magnetic Switching Triggered by Proton-Coupled Electron-Transfer Assisted by Long-Distance Proton-Alkali Cation Transport

International audienc