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The aim of this study is to discus different numerically models for the simulation of moving contact lines in the context of a Volume of Fluid–Continuum Surface Force (VoF–CSF) method. We focus on the particular situation of spreading drops. We first present the numerical methods used for the simulation of moving contact line i.e. static contact angle versus dynamic contact angle, no slip condition versus slip condition. A grid and time convergence is performed for the different models. We show that the integration of the Continuum Surface Force using the finite volume method results in a grid dependence at the onset of the spreading. The static and dynamic models are compared to experiments. It is shown that the dynamic models based on the Cox’s relation for the dynamic contact angle are able to reproduce experiments while static models overestimate the spreading time and are not able to reproduce the Tanner regime. The difference between static and dynamic models is shown to increase with the Ohnesorge number. [ABSTRACT FROM AUTHOR]

Bioresorbable polymeric materials have risen great interest as implants for bone tissue regeneration, since they show substantial advantages with respect to conventional metal devices, including biodegradability, flexibility, and the possibility to be easily modified to introduce specific functionalities. In the present work, an innovative nanocomposite scaffold, properly designed to show biomimetic and osteoinductive properties for potential application in bone tissue engineering, was developed. The scaffold is characterized by a multi-layer structure, completely different with respect to the so far employed polymeric implants, consisting in a poly(d,l-lactide-co-glycolide)/polyethylene glycol electrospun nanofibrous mat sandwiched between two hydrogel gelatin layers enriched with tantalum nanoparticles (NPs). The composition of the electrospun fibers, containing 10 wt% of polyethylene glycol, was selected to ensure a proper integration of the fibers in the gel phase, essential to endow the composite with flexibility and to prevent delamination between the layers. The scaffold maintained its structural integrity after six weeks of soaking in physiological solutions, albeit the gelatin phase was partially released. The combined use of gelatin, bioresorbable electrospun fibers and tantalum NPs endows the final device with biomimetic and osteoinductive properties. Indeed, results of the in vitrotests demonstrate that the obtained scaffolds clearly represent a favorable milieu for normal human bone-marrow derived mesenchymal stem cells viability and osteoblastic differentiation; moreover, inclusion of tantalum NPs in the scaffold improves cell performance with particular regard to early and late markers of osteoblastic differentiation.

Dès les premières semaines de l’épidémie de la Covid-19, en France, plusieurs voix se sont levées pour dire que l’heure n’était pas à la réflexion éthique, mais à l’action, en soulignant néanmoins l’importance d’un retour d’expérience à l’issue de l’urgence. Dans cette visée, le Centre d’éthique clinique de l’AP–HP a proposé, dès la fin du 1erconfinement national, à des soignants, comme à des patients ou à des proches, de revenir, s’ils le souhaitaient, sur les questionnements ou les difficultés éthiques rencontrées pendant cette période (ce qu’il a appelé des « relectures éthiques »). Entre mai et septembre 2020, 31 professionnels y ont participé, 1 seul patient (médecin à la retraite) a été rencontré et aucun proche. Cet article souhaite partager la façon dont ces professionnels sont revenus, dans l’après-coup, sur les premiers mois de la crise. Plus d’une année plus tard, à l’heure où ce qui était « inhabituel » commence par devenir « ordinaire », et le « retour à la vie normale » semble à l’horizon, il n’est pas inutile de rappeler leurs réactions, leurs interrogations et leurs malaises. Au croisement des entretiens, c’est un questionnement quant à ce que soigner veut dire aujourd’hui et au rôle de la médecine en contexte de crise que l’on voit émerger.

Calcium phosphate cements are biocompatible, bioactive, and osteogenic systems which have the potential to mimic the mineral phase of native bone and the ability to be molded into bone defects and implant sites, then harden in situto provide stability. However, their mechanical strength needs to be improved: In the last few decades, the incorporation of preformed fibers into a brittle cement matrix has been proven to increase the mechanical properties. To obtain a better cohesion between the fibers and the cement paste thus improving the mechanical performances, in this work, we attempted the formation of self-assembling fibers in a single step during the setting of our calcium phosphate cement formulations.

BACKGROUND AND AIMS: The genetic load in coeliac disease has hitherto been inferred from case series or anecdotally referred twin pairs. We have evaluated the genetic component in coeliac disease by estimating the concordance rate for the disease among twin pairs in a large population based study. METHODS: The Italian Twin Registry was matched with the membership lists of a patient support group. Forty seven twin pairs were recruited and screened for antiendomysial (EMA) and antihuman-tissue transglutaminase (anti-tTG) antibodies; zygosity was verified by DNA fingerprinting and twins were typed for HLA class II DRB1 and DQB1 molecules. RESULTS: Concordance rates for coeliac disease differ significantly between monozygotic (MZ) (0.86 probandwise and 0.75 pairwise) and dizygotic (DZ) (0.20 probandwise and 0.11 pairwise) twins. This is the highest concordance so far reported for a multifactorial disease. A logistic regression model, adjusted for age, sex, number of shared HLA haplotypes, and zygosity, showed that genotypes DQA1*0501/DQB1*0201 and DQA1*0301/DQB1*0302 (encoding for heterodimers DQ2 and DQ8, respectively) conferred to the non-index twin a risk of contracting the disease of 3.3 and 1.4, respectively. The risk of being concordant for coeliac disease estimated for the non-index twin of MZ pairs was 17 (95% confidence interval 2.1-134), independent of the DQ at risk genotype. CONCLUSION: This study provides substantial evidence for a very strong genetic component in coeliac disease, which is only partially due to the HLA region.

OBJECTIVE: Coeliac disease (CD) is associated with autoimmune thyroid disease. Gluten sensitivity represents a spectrum, with at one end cases with severe gluten-dependent enteropathy, and at the other subjects with minor signs of deranged mucosal immune response. The aim of this paper was to look for signs of minor small bowel injury and immunohistochemical markers of gluten sensitivity in a group of patients with Hashimoto's disease. SUBJECTS AND METHODS: Fourteen patients with Hashimoto's thyroiditis without serological evidence of CD underwent immunohistochemical analysis of jejunal biopsies. RESULTS: In 6/14 cases (43%) an increased density of gammadelta T cell receptor bearing intra-epithelial lymphocytes was found. In 6/14 (43%) signs of mucosal T cell activation (presence of interleukin 2 (IL2) receptor (CD25) on lamina propria T cells and/or expression of human lymphocyte antigen (HLA)-DR molecules on crypt epithelial cells) were noted. In 4 out of 6 such cases, HLA haplotypes were described in association with CD. CONCLUSION: A significant proportion of patients with Hashimoto's thyroiditis present signs of 'potential' CD and of activated mucosal T cell immunity. The gluten dependence of such findings remains to be ascertained.

The endocrine pancreas of the teleost fish Blennius gattoruggine was studied by immunochemistry using both light and electron microscopy. Generally, one large Brockmann body, along with intermediate and small islets, was found. Cells immunoreactive (IR) to anti-insulin (B), anti-glucagon (A) anti-somatostatin (D) anti-pancreatic polypeptide and anti-PYY sera were detected with B cells located at the center of the islet and the other cell types forming a peripheral mantle. The B-cell cytoplasm showed rows of microtubules close to the secretory granules and perpendicular to the plasmalemma. The ultrathin section images revealed exocytotic and endocytotic features, and the presence of intercellular gap junctions between the plasmalemma of contiguous cells, suggesting intercellular routes of communication, e.g. via autocrine and/or paracrine mechanism. These features were observed in all of the cell types, and were abundant in D cells. D cells were particularly numerous in the islets and were disposed close to A and B cells, as observed in other teleost species. The most peripheral B cells, in closer contact with D cells than the central ones, appeared strongly immunolabeled, perhaps owing to the inhibitory action of somatostatin. Some D cells exhibited a long protrusion directed towards the center of the islet. In view of their cytological characteristics and their secretion, D cells might have an important role in the modulation of A and B-cell secretion in an endocrine and/or paracrine fashion.

We investigated how different plasma glucose concentrations could significantly modify the C-peptide response to glucagon. Twenty poorly-controlled (HbA1c 10.2 ± 1.5%) non insulin-dependent (NIDDM) subjects (body mass index 27 ± 1.8), 2 treated with diet alone and 18 with oral hypoglycemic agents were studied. The first day glucagon (1 mg iv) was injected, patients being fasting and untreated. Mean plasma glucose levels were 11.4 ± 1.2 mM. On a second non consecutive day, after an overnight fast, the same patients were connected to a closed-loop insulin infusion system (Betalike, Genoa), their blood glucose concentrations were stabilized within a normoglycemic range (5–5.5 mM) for 2 h and insulin infusion was stopped. The glucagon test was repeated 30 min later. Blood samples were taken 0, 6, 10, 20 min after glucagon injection. In the second test, basal, and 6,10 and 20 min post-glucagon glucose levels were significantly lower (p < 0.001); similarly C-peptide concentrations were significantly reduced both in basal conditions (0.55 ± 0.04 vs 0.37 ± 0.04 nM; p < 0.001) and 6 (0.92 ± 0.06 vs 0.6 ± 0.06; p < 0.001), 10 (0.79 ± 0.06 vs 0.56 ± 0.06; p < 0.001) and 20 min (0.64 ± 0.05 vs 0.44 ± 0.04; p < 0.001) after stimulation. The C-peptide secretion area showed the same trend (49.5 +4.8 vs 32.1 ±5.8; p< 0.001). In conclusion, our data confirms that blood glucose levels modulate the pancreatic insulin secretion; glycémie normalization significantly reduced both basal and post-glucagon C-peptide release.

The endocrine pancreas of three red frogs was studied immunohistochemically. It consisted of islets and diffuse endocrine cells. The islets showed a mammalian-like arrangement with a central core of B cells and a peripheral mantle of A/PP cells. A few D and VIP cells were also present. Several regulatory peptides were co-localized in the same endocrine cells by consecutive sections and double-labeling studies. The A/PP cells were formed by subpopulations of cells showing various types of immunoreactivity and varying degrees of immunolabeling. Generally, glucagon/pancreatic polypeptide, glucagon/pancreatic polypeptide/peptide tyrosine tyrosine and glucagon/pancreatic polypeptide/neuropeptide tyrosine immunoreactivities were present in the islets and in the endocrine cells scattered throughout the exocrine parenchyma (the diffuse component). Some specimens, mainly belonging to Rana dalmatina, showed evident periinsular halos around the islets. The diffuse component was abundant, and mainly contained A/PP cells. It formed a net across the exocrine parenchyma; its interrelationship with the latter might occur by a paracrine mechanism.

We studied the effects of a premeal sc injection of an analog of somatostatin (SMS 201–995, Sandoz) on the postprandial glycemic excursions, insulin requirement and hormone profiles (GH, glucagon and C-peptide) in 8 IDDM patients (diabetes duration 14.0 ± 6.5 yr, daily insulin requirement 36 ± 6.4 U) maintained normoglycemic by connecting them to a closed-loop insulin infusion system (Betalike, Genoa). The morning of the test the patients were connected to the Betalike and their glucose levels stabilized for at least 4 h. At 13:00 h the study was begun with a sc injection of 50 μg of SMS 201–995 or placebo (randomly) and a standardized mixed meal (800 Kcal) was given. Blood samples were obtained 0, 15, 30, 60, 120 and 180 min after the injection. Each patient was tested both with SMS 201–995 and placebo. Postmeal glycemic peaks were decreased after SMS 201–995 (119.6 ± 5.4 mg /dl vs 149.1 ± 4.2; p< 0.05) as well as insulin requirements (3.2 ± 0.8 U vs 13.3 ± 1.9; p< 0.01) for the 180 min postprandial period. Similarly, glucagon level was reduced 30 min postprandially (24 ± 6 pg / ml vs 59 ± 24; p< 0.05) and so GH level only 180 min after lunch (p< 0.05). The premeal injection of SMS decreases postprandial glycemic excursions and the corresponding insulin requirement. The action of SMS 201–995 may be mainly mediated by the suppression of postprandial glucagon peak.

Summary.Dispersed cells from cultured mouse cell lines, mouse macrophages, and inert microspheres were layered onto outgrowing mouse trophoblast in culture. The cells that settled onto the trophoblast remained round, in contrast to the elongated spreading shape they assumed on the glass substratum. The cells were readily dislodged from the trophoblast surface, whereas the microspheres were strongly adherent to trophoblast within 30 min. Scanning electron microscopy showed that trophoblast engulfed the spheres, but not the cells. Despite the lack of adhesion between cells and trophoblast, cell processes connected the two. The inability of cells to adhere to the free surface of the trophoblast could explain the trophoblast's ability to induce contact inhibition in co-cultured cells.

Cet articles’arrête sur les malaises et les arguments éthiques des personnes qui ont saisi le Centre d’éthique clinique de l’AP-HP pendant le 1erconfinement national. L’analyse a posteriori de ces échanges, ainsi que l’absence de la voix des patients pendant cette période, conduisent à une réflexion quant au rôle de chacun – professionnels du sanitaire et du médicosocial, proches et citoyens – dans ce contexte particulier. Elle invite à repenser la responsabilité médicale, la démocratie sanitaire et l’éthique (clinique) en temps de crise.